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Case 55: Large right mandibular mass
CLINICOPATHOLOGIC CONFERENCES J Oral Maxillofac Surg 43:531-536, 1985
Case 55: Large Right Mandibular Mass ROCCO R. ADDANTE, DMD, MD,* AND JEFFREY L. LASKIN, DDS, MSt manent molar and demonstrated calcific projections medially (Fig. 5). Laboratory analysis disclosed normal complete blood count (CBC), differential count, blood urea nitrogen (BUN), erythrocyte sedimentation ratc (ESR), calcium, phosphorus, and alkaline phosphatase. Urinalysis showed no abnormalities. The chest radiograph was unremarkable.
Case Presentation A six-year-old boy was referred to the Oral Surgery Service at the Dartmouth-Hitchcock Medical Center, Hanover, New Hampshire with right submandibular swelling. The child's mother first noticed the asymmetry one month prior to the referral and believed it to be rapidly enlarging. There was no associated pain, fever" dysphagia, paresthesia, or limitation of motion. Both patient and parent denied any history of trauma, recent dental intervention, or prior radiation therapy. The past medical history was entirely unremarkable, and a complete review of systems was noncontributory. No history of foreign travel or close association with pets or farm animals was elicited. No illnesses were reported in the immediate household. On clinical examination the patient was healthy-appearing, afebrile, and behaving appropriately, with a 5 x 7 em firm, nontender, nonulcerated, nonerythematous mass projecting in an inferior and medial direction from the right body of the mandible (Fig. I). The mass itself was firm but not bone-hard and was fixed to the mandible. Bimanual palpation revealed extension to the midline. No bruits or thrills were noted. There was no cervical lymphadenopathy and no thyroid enlargement. Intraoral examination revealed a full range of mandibular motion with normal dentition and gingival architecture. No fluctuance or elevation of the floor of the mouth was seen. Normal flow was evident from major salivary ducts bilaterally. The remainder of the head and neck examination was within normal limits. Cardiothoracic auscultation revealed a regular rhythm of 80 bpm, without murmurs, and normal breath sounds bilaterally. The abdomen was soft without masses, and the extremities displayed a full range of motion. Neurologic and dermatologic examinations were unremarkable. The mass was examined with plain films, xeroradiograms, and a computed tomographic (CT) scan. A welldefined radiolucency was detected in the right mandibular body subapical to the developing teeth, measuring approximately 2.5 x I cm (Fig. 2). There was no interruption of the inferior cortex. Bony trabeculae appeared to emanate from the inferior cortex in a perpendicular fashion into the soft tissue mass (Fig. 3). This was highlighted on the xerogram (Fig. 4). The CT scan showed erosion of the lingual cortex at the level of the first per-
Differential Diagnosis
Dr. Jeffrey L. Laskin This six-year-old boy presented with an asymptomatic, rapidly enlarging mass associated with the right mandibular body. Past medical history, review of systems, and laboratory analysis were all noncontributory. The mass itself was firm and fixed to the mandible, and all other clinical findings were normal. A thorough radiographic examination demonstrated a well-defined mandibular radiolucent defect with erosion of the lingual cortex and bony trabeculae projecting from the inferior cortex medially and inferiorly into the mass. These findings would tend to point to a neoplastic process originating within the mandible itself. An infectious process is unlikely since there were no
* Assistant Professor of Clinical Surgery, Section of Plastic and Oral Surgery, Dartmouth-Hitchcock Medical Center, Hanover, New Hampshire. t Assistant Professor, and Director of Advanced Education, University of Florida College of Dentistry, Gainesville, Florida. Address correspondence and reprint requests to Dr. Addante: The Hitchcock Clinic, 2 Maynard St., Hanover, NH 03756.
FIGURE I. Clinical view of facial asymmetry caused by submandibular swelling.
531
532
CASE 55
F IG URE 2 (upper left ). Pano ramic radiog raph s how ing large rad iol ucency of the mandible. FI G URE 3 (upp er rig ht }, Posteroan terior rad iogra ph showing rad ioluce ncy in the right body of the ma nd ibl with bony pro jec tions infe rio rly. PIG URE 4 (lo wer left ). Late ral xe rorad iograph of the mandible sh owing uniloc ula r radiol ucenc y, integri ty of the infe rior co rte x, and bo ny trab ecu lation ex te nd ing into the soft tiss ue mass. F IGU R E 5 (lo wer rig ht ). Co mputed tomograph ic scan de monstrating perfo ration of the lingual corte x of the mandible and media l ca lcific projections .
symptoms indicating an infection and all laboratory studies were normal. Garre's proliferative periostitis could have been a consideration but there is no obvious clinical or laboratory evidence to substantiate it. Odontogenic tumors are also an unlikely consideration because of the rapid growth rate and radiographic appearance. Although they do appear
as radiolucent lesions, such lesions usually have a distinct bony margin and rarely destroy the cortex.l-! The aneurysmal bone cyst occurs in young persons, usually in the anterior body area of the mandible, but can occur in the angle also. Ra-. diographically, it appears as a multilocular expansile defect. Rapid growth, especially associated
533
ADDANTE AND LASKIN
.I I J
• FIGURE 6 (left). x 100).
Photomicrograph showing a homogeneous proliferation of spindle-like cells (hematoxylin and eosin. magnification
FIGURE 7 (right). Photomicrograph demonstrating fibroblasts and fibroc ytes in a dense fibrillar coll agen matrix (hematoxylin and eosin. magnification x 250).
with trauma, has been reported and pain is often associated with this lesion.I.2 ·6.7 Neither of these findings were present in this case. The possibility of a malignant neoplastic process must be considered due to the short duration, rapid growth rate, and locally destructive nature of this lesion. The osteolytic form of an osteosarcoma can occur at an early age. There is often pain and/or paresthesia associated with this neoplasm. Additionally, a history of trauma has been reported prior to the appearance of the se lesions .t -? In this case, however, none of these factors were present. Fibrosarcoma, Ewing's sarcoma, and malignant lymphoma of bone have to be considered, but their rare occurrence in the jaw gives them a low priority in a differential dlagnosis.l-? A locally aggressive benign neoplastic process that occurs in young individuals would seem to be the most likely lesion of concern. These include the desmoplastic fibroma, juvenile fibromatosis, and the fibrous histiocytoma.l ? The desmoplastic fibroma occurs centrally in bone, and is expansile and locally destructive. It is usually painless and can occur in the posterior body region of the mandible . It occurs most commonly in the first three decades of life and can grow quite rapidly. Swelling of the jaw is the most common first symptom. Radiographically, the lesion usually appears as a welldelin eated radiolucency, either unilocular or multilocular. I •2 •5 Juvenile fibromatosis is a locally aggressive benign condition that can expand rapidly and destroy bone. It can be non tender and does occur in young individuals, although it is quite uncommon in the jaws.lr" The fibrous histiocytoma is a benign, unencapsulated, and often richly vascular lesion. Occurrence in the jaw is relatively un-
common. 1,2 Of the three lesions, the desmoplastic fibroma most closely fits the description of the lesion de scribed in this young patient. Subsequent Clinical Course Four days after the initial presentation, the patient under went an extraoral incisional biopsy. Fungal, aerobic, and anaerobic cultures were obtained, although no purulence was noticed. The lesion was firm and uniform in consistency. Microscopic sections revealed a homogeneous proliferation of spindle-shaped cells in a fibrous matrix (Figs. 6 and 7). The proliferating cells had elongated to ovoid nuclei, with no significant mitotic activity. Masson's trichrome stain revealed large foci of collagenous connective tissue. A diagnosis of a desmoplastic fibroma of the right jaw was made . Electron microscopy supported the diagnosis ofa fibroblastic proliferation consistent with a desmoid tumor. Due to the aggressive nature of these tumors and their high recurrence rate, the patient underwent en bloc resection of the mass with a segmental mandibulectomy two weeks after biopsy (Fig. 8). The lesion appeared to have arisen from within the mandible and to have eroded through the lingual cortex. The mass was firm and rubbery, without obvious invasion into the surrounding musculature. Immediate reconstruction was accomplished with an iliac crest bone graft (Fig. 9). Microscopic examination of the surgical specimen showed pseudoencapsulation, with tumor present at both the anterior and posterior margins of the specimen despite what appeared to be clinically adequate margins . The patient did well until2 1h weeks postoperatively, at which time purulence was noticed from the submandibular incision. In light of the po sitive margins, it was elected to remove the graft rather than to attempt to salvage it. One week later, the graft was excised and new margins were established, sacrificing the symphyseal region. Histologic examination disclo sed all margins free of tumor. Delayed reconstruction was performed five months later, with an iliac crest bone graft from the opposite hip . The patient has done well postoperatively.
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CASE 55
FIGURE 8 (left). Resected specimen photographed from the lingual aspect showing centrally arising neoplasm with extension through the lingual cortex. FIGURE 9 (right).
Panoramic radiograph showing initial resection margins and reconstruction with an interposed iliac bone graft.
with a full range of mandibular motion and no evidence of recurrence at two years after surgery (Fig. 10). Discussion
The fibromatoses are a group of fibrous connective lesions that often fall in the gray zone between categorically benign and malignant tumors.f-? This expanse is reflected by the variety of terms used to describe lesions within this family such as desmoid tumors, abdominal desmoids, extra-abdominal desmoids, desmoplastic fibromas, aggressive juvenile fibromatoses, congenital generalized fibromatoses, low-grade fibrosarcomas, etc. The clinician must not consider only the histologic characteristics of such lesions, but must also take into account the origin of the lesion and the clinical course in selecting treatment alternatives. A historical review of the desmoplastic fibroma begins with the original description by MacFarlene in 1832 and its subsequent naming as desmoid tumor by Mueller in 1838, to both referring exclusively to the hard fibroma seen in the musculature of the anterior abdominal wall. In 1956, Paget correlated the histologic appearance of these fibromas with similar lesions in other anatomical sites, specifically the shoulder girdle and upper arm. 11 Jaffe in 1958 was the first to describe these extra-abdominal desmoids in bone and coined the term "desmoplastic fibroma. "12 He presented five cases involving the tibia, scapula, and femur, and in formulating the term desmoplastic fibroma indicated "the densely fibrous character of the lesional
tissue, which makes it resemble the familiar desmoid tumor of the abdominal wall." Griffith and Irby in 1965 reported what they concluded was the first case of a desmoplastic fibroma occurring in facial bones.P They described an 8year-old Caucasian girl with a palpable expansion of the left body of the mandible. The lesion was composed of mature, proliferating fibroblastic tissue found to erode and penetrate the cortical plate. Throughout the article the terms desmoid tumor and desmoplastic fibroma are used interchangeably. Since the publication of Jaffe's report, numerous small series and case reports have appeared, including work by Fisker and Philipsen,!" who identified 14 cases of desmoplastic fibroma of the mandible in addition to their own case report. The world literature was reviewed in 1978 by Freedman et al.,15 who reported a total of 25 cases. Interestingly, they Included only lesions clearly described as having arisen as primary central tumors of the jaw. Cases in which the tumor appeared to have arisen peripherally with subsequent secondary erosion of the jaw bones, such as that reported by Peede and Epker.!" were not included. As one follows the ensuing literature, the observation is made that lesions that arise centrally in bone are referred to as desmoplastic fibromas, whereas those that arise peripherally with possible bony invasion are termed aggressive fibromatoses. This division may have significant implications in reporting future cases and in assessing recurrence rates and appropriate treatment modalities for the two conditions. Shafer
535
ADDANTE AND LASKIN
defines a desmoplastic fibroma as a lesion of bone, including the jaws, which is histologically indistinguishable from aggressive fibromatoses or the extra-abdominal desrnoid.I Therefore, the true differentiation of these similar fibrous tumors and their treatment should be based on a review of the clinical behavior of the neoplasm and the radiographic findings, in addition to the gross and microscopic appearances. The consensus of various case reports indicates that clinically the desmoplastic fibroma (desmoid tumor) presents as a nontender, rapidly enlarging mass that causes little or no functional impairment. It is predominantly a disease of younger people, with a peak incidence in the second decade. I7 Attention is usually sought when facial asymmetry becomes apparent. Although rare, the majority have been reported in the mandible, with only four cases reported in the maxilla. IS Radiographically, they are radiolucent with welldefined sclerotic borders, some trabeculation, and expansile thin cortices. Some lesions have been reported with ill-defined borders suggesting malignancy. They may appear as unilocular or multilocular lesions. Grossly, the tumor is white or grayish-white in color and has a firm, almost rubbery consistency. It has a smooth, unencapsulated surface. Histologically, the neoplasm consists of fibrous tissue that varies throughout the lesion. Some areas show sparse fibroblasts in a field of dense intercellular collagen, whereas in other areas the fibroblasts may predominate and produce a whorled pattern.'? Nuclear atypia and mitotic activity are distinctly absent and serve to differentiate this lesion from a frank fibrosarcoma. Although morphologically benign, the lesion is infiltrative and can extend well beyond its clinical boundaries as this case illustrates. Accordingly, at Memorial Sloan-Kettering Cancer Center, desmoid tumors are regarded as low-grade fibrosarcornas.P The absence of osteoid differentiates this tumor from fibrous dysplasias. The lack of giant cells and foam cells helps to distinguish it from nonossifying fibromas. The most remarkable feature of this neoplasm is its tendency to recur, usually at the site of prior surgical excision. A total of 376 cases of extra-abdominal desmoids are reported with a recurrence rate of 6;3%.21 This figure, however, represents all extra-abdominal desmoids and tends to lump desmoplastic fibromas with aggressive fibromatoses. These entities may in fact have differing recurrence rates and there may be a role for thorough curettage with the central desmoplastic fibroma. For example, in the tumor reported by Fisker and Phil-
FIGURE 10. Photograph of the patient one year following definitive reconstruction.
ipsen in the anterior mandible.!" treatment consisted of thorough currettage with no recurrence after two years. The authors, however, recommend block resection in those cases where cortical bone is destroyed. The best therapy is elusive at present because of the relatively few reported cases and short follow-up studies. The experience at SioanKettering shows that excision with clear surgical margins offers the best chance for a recurrence-free course (Haidu SI, personal communication). Radiation therapy is not advised and may lead to sarcomatous transforrnation.P'P References I. Bastsakis JC: Tumors of the Head and Neck, 2nd ed. Baltimore. Williams & Wilkins, 1979 2. Shafer WC, Hine MK, Levy BM: A Textbook of Oral Pathology, 4th ed. Philadelphia, WB Saunders, 1983 3. Henefer EP, Bishop HC, Brown A: Juvenile fibromatosis with invasion of the mandible: report of two cases. Oral Surg 36:965, 1978 4. Peede LF Jr., Epker BN: Aggressive juvenile fibromatosis involving the mandible: surgical excision with immediate reconstruction. Oral Surg 43:651, 1977 5. Hinds EC, Kent IN, Fechner RE: Desmoplastic fibroma of the mandible: report ofa case. Oral Surg 27:271,1969 6. Laskin JL, Lebowitz MS, Baughman RA. et al: Clinicopathologic Conferences, Case 38, Part I. J Oral Maxillofac Surg 40:169, 1982 7. Laskin JL, Lebowitz MS, Baughman RA, et al: Clinicopathologic Conferences: Aneurysmal Bone Cyst of the Mandible, Case 38, Part II. J Oral Maxiliofac Surg 40:219, 1982 8. Allen PW: The fibromatoses: a clinicopathologic classification based on 140 cases. Part I. Am J Surg Pathol 1:255, 1977 9. Allen PW: The fibromatoses: a clinicopathologic classification based on 140 cases. Part II. Am J Surg Pathol 1:305, 1977 10. Pack GT, Ehrick HE: Neoplasms of the anterior abdominal wall with special consideration of desmoid tumors. Int Abst Surg 79:177, 1944 I I. Paget J: Fibronucleated tumor of the abdomen of 14 years growth; removal. Lancet 1:625, 1956
536 12. Jaffe HL: Tumors and Tumorous Conditions of the Bones and Joints. Philadelphia, Lea & Febiger, 1958, p 298 13. Griffith JG, Irby WB: Desmoplastic fibroma. Oral Surg 20:269, 1965 14. Fisker AV, Philips en HP: Desmoplastic fibroma of the jaw bones, Int J Oral Surg 5:285, 1976 15. Freedman PD, Cardo V, Kerpel S, et al: Desmoplastic fibroma (fibromatosis) of the jaw bones. Oral Surg 46:386, 1978 16. Peede LF, Epker BN: Aggressive juvenile fibromatosis involving the mandible: surgical excision with immediate reconstruction. Oral Surg 43:651, 1977 17. Sigura I: Desmoplastic fibroma: cast report and review of the literature. J Bone Joint Surg 58A:126, 1976
CASE 55
18. Eisen MZ, Butler HE: Desmoplastic fibroma of the maxilla: report of a case. J Am Med Assoc 108:608, 1984 19. Cunningham CD, Smith RO, Enriquez P, et al: Desmoplastic fibroma of the mandible: a case report. Ann Otol Rhinol Laryngo184:125,1975 20. Hajdu SI: Pathology of Soft Tissue Tumors. Philadelphia, Lea & Febiger, 1979, p 122 21. Hajdu SI: Pathology of Soft Tissue Tumors. Philadelphia, Lea & Febiger, 1979, p 128 22. Dahlin DC, Hoover NW: Desmoplastic fibroma of bone: report of two cases. J Am Med Assoc 188:685, 1964 23. Soule EH, Scanlon PW: Fibrosarcoma arising in an extraabdominal desmoid tumor: report of a case. Mayo Clin Proc 37:443, 1962
Case 55: Large Right Mandibular Mass ROCCO R. ADDANTE, DMD, MD,* AND JEFFREY L. LASKIN, DDS, MSt manent molar and demonstrated calcific projections medially (Fig. 5). Laboratory analysis disclosed normal complete blood count (CBC), differential count, blood urea nitrogen (BUN), erythrocyte sedimentation ratc (ESR), calcium, phosphorus, and alkaline phosphatase. Urinalysis showed no abnormalities. The chest radiograph was unremarkable.
Case Presentation A six-year-old boy was referred to the Oral Surgery Service at the Dartmouth-Hitchcock Medical Center, Hanover, New Hampshire with right submandibular swelling. The child's mother first noticed the asymmetry one month prior to the referral and believed it to be rapidly enlarging. There was no associated pain, fever" dysphagia, paresthesia, or limitation of motion. Both patient and parent denied any history of trauma, recent dental intervention, or prior radiation therapy. The past medical history was entirely unremarkable, and a complete review of systems was noncontributory. No history of foreign travel or close association with pets or farm animals was elicited. No illnesses were reported in the immediate household. On clinical examination the patient was healthy-appearing, afebrile, and behaving appropriately, with a 5 x 7 em firm, nontender, nonulcerated, nonerythematous mass projecting in an inferior and medial direction from the right body of the mandible (Fig. I). The mass itself was firm but not bone-hard and was fixed to the mandible. Bimanual palpation revealed extension to the midline. No bruits or thrills were noted. There was no cervical lymphadenopathy and no thyroid enlargement. Intraoral examination revealed a full range of mandibular motion with normal dentition and gingival architecture. No fluctuance or elevation of the floor of the mouth was seen. Normal flow was evident from major salivary ducts bilaterally. The remainder of the head and neck examination was within normal limits. Cardiothoracic auscultation revealed a regular rhythm of 80 bpm, without murmurs, and normal breath sounds bilaterally. The abdomen was soft without masses, and the extremities displayed a full range of motion. Neurologic and dermatologic examinations were unremarkable. The mass was examined with plain films, xeroradiograms, and a computed tomographic (CT) scan. A welldefined radiolucency was detected in the right mandibular body subapical to the developing teeth, measuring approximately 2.5 x I cm (Fig. 2). There was no interruption of the inferior cortex. Bony trabeculae appeared to emanate from the inferior cortex in a perpendicular fashion into the soft tissue mass (Fig. 3). This was highlighted on the xerogram (Fig. 4). The CT scan showed erosion of the lingual cortex at the level of the first per-
Differential Diagnosis
Dr. Jeffrey L. Laskin This six-year-old boy presented with an asymptomatic, rapidly enlarging mass associated with the right mandibular body. Past medical history, review of systems, and laboratory analysis were all noncontributory. The mass itself was firm and fixed to the mandible, and all other clinical findings were normal. A thorough radiographic examination demonstrated a well-defined mandibular radiolucent defect with erosion of the lingual cortex and bony trabeculae projecting from the inferior cortex medially and inferiorly into the mass. These findings would tend to point to a neoplastic process originating within the mandible itself. An infectious process is unlikely since there were no
* Assistant Professor of Clinical Surgery, Section of Plastic and Oral Surgery, Dartmouth-Hitchcock Medical Center, Hanover, New Hampshire. t Assistant Professor, and Director of Advanced Education, University of Florida College of Dentistry, Gainesville, Florida. Address correspondence and reprint requests to Dr. Addante: The Hitchcock Clinic, 2 Maynard St., Hanover, NH 03756.
FIGURE I. Clinical view of facial asymmetry caused by submandibular swelling.
531
532
CASE 55
F IG URE 2 (upper left ). Pano ramic radiog raph s how ing large rad iol ucency of the mandible. FI G URE 3 (upp er rig ht }, Posteroan terior rad iogra ph showing rad ioluce ncy in the right body of the ma nd ibl with bony pro jec tions infe rio rly. PIG URE 4 (lo wer left ). Late ral xe rorad iograph of the mandible sh owing uniloc ula r radiol ucenc y, integri ty of the infe rior co rte x, and bo ny trab ecu lation ex te nd ing into the soft tiss ue mass. F IGU R E 5 (lo wer rig ht ). Co mputed tomograph ic scan de monstrating perfo ration of the lingual corte x of the mandible and media l ca lcific projections .
symptoms indicating an infection and all laboratory studies were normal. Garre's proliferative periostitis could have been a consideration but there is no obvious clinical or laboratory evidence to substantiate it. Odontogenic tumors are also an unlikely consideration because of the rapid growth rate and radiographic appearance. Although they do appear
as radiolucent lesions, such lesions usually have a distinct bony margin and rarely destroy the cortex.l-! The aneurysmal bone cyst occurs in young persons, usually in the anterior body area of the mandible, but can occur in the angle also. Ra-. diographically, it appears as a multilocular expansile defect. Rapid growth, especially associated
533
ADDANTE AND LASKIN
.I I J
• FIGURE 6 (left). x 100).
Photomicrograph showing a homogeneous proliferation of spindle-like cells (hematoxylin and eosin. magnification
FIGURE 7 (right). Photomicrograph demonstrating fibroblasts and fibroc ytes in a dense fibrillar coll agen matrix (hematoxylin and eosin. magnification x 250).
with trauma, has been reported and pain is often associated with this lesion.I.2 ·6.7 Neither of these findings were present in this case. The possibility of a malignant neoplastic process must be considered due to the short duration, rapid growth rate, and locally destructive nature of this lesion. The osteolytic form of an osteosarcoma can occur at an early age. There is often pain and/or paresthesia associated with this neoplasm. Additionally, a history of trauma has been reported prior to the appearance of the se lesions .t -? In this case, however, none of these factors were present. Fibrosarcoma, Ewing's sarcoma, and malignant lymphoma of bone have to be considered, but their rare occurrence in the jaw gives them a low priority in a differential dlagnosis.l-? A locally aggressive benign neoplastic process that occurs in young individuals would seem to be the most likely lesion of concern. These include the desmoplastic fibroma, juvenile fibromatosis, and the fibrous histiocytoma.l ? The desmoplastic fibroma occurs centrally in bone, and is expansile and locally destructive. It is usually painless and can occur in the posterior body region of the mandible . It occurs most commonly in the first three decades of life and can grow quite rapidly. Swelling of the jaw is the most common first symptom. Radiographically, the lesion usually appears as a welldelin eated radiolucency, either unilocular or multilocular. I •2 •5 Juvenile fibromatosis is a locally aggressive benign condition that can expand rapidly and destroy bone. It can be non tender and does occur in young individuals, although it is quite uncommon in the jaws.lr" The fibrous histiocytoma is a benign, unencapsulated, and often richly vascular lesion. Occurrence in the jaw is relatively un-
common. 1,2 Of the three lesions, the desmoplastic fibroma most closely fits the description of the lesion de scribed in this young patient. Subsequent Clinical Course Four days after the initial presentation, the patient under went an extraoral incisional biopsy. Fungal, aerobic, and anaerobic cultures were obtained, although no purulence was noticed. The lesion was firm and uniform in consistency. Microscopic sections revealed a homogeneous proliferation of spindle-shaped cells in a fibrous matrix (Figs. 6 and 7). The proliferating cells had elongated to ovoid nuclei, with no significant mitotic activity. Masson's trichrome stain revealed large foci of collagenous connective tissue. A diagnosis of a desmoplastic fibroma of the right jaw was made . Electron microscopy supported the diagnosis ofa fibroblastic proliferation consistent with a desmoid tumor. Due to the aggressive nature of these tumors and their high recurrence rate, the patient underwent en bloc resection of the mass with a segmental mandibulectomy two weeks after biopsy (Fig. 8). The lesion appeared to have arisen from within the mandible and to have eroded through the lingual cortex. The mass was firm and rubbery, without obvious invasion into the surrounding musculature. Immediate reconstruction was accomplished with an iliac crest bone graft (Fig. 9). Microscopic examination of the surgical specimen showed pseudoencapsulation, with tumor present at both the anterior and posterior margins of the specimen despite what appeared to be clinically adequate margins . The patient did well until2 1h weeks postoperatively, at which time purulence was noticed from the submandibular incision. In light of the po sitive margins, it was elected to remove the graft rather than to attempt to salvage it. One week later, the graft was excised and new margins were established, sacrificing the symphyseal region. Histologic examination disclo sed all margins free of tumor. Delayed reconstruction was performed five months later, with an iliac crest bone graft from the opposite hip . The patient has done well postoperatively.
534
CASE 55
FIGURE 8 (left). Resected specimen photographed from the lingual aspect showing centrally arising neoplasm with extension through the lingual cortex. FIGURE 9 (right).
Panoramic radiograph showing initial resection margins and reconstruction with an interposed iliac bone graft.
with a full range of mandibular motion and no evidence of recurrence at two years after surgery (Fig. 10). Discussion
The fibromatoses are a group of fibrous connective lesions that often fall in the gray zone between categorically benign and malignant tumors.f-? This expanse is reflected by the variety of terms used to describe lesions within this family such as desmoid tumors, abdominal desmoids, extra-abdominal desmoids, desmoplastic fibromas, aggressive juvenile fibromatoses, congenital generalized fibromatoses, low-grade fibrosarcomas, etc. The clinician must not consider only the histologic characteristics of such lesions, but must also take into account the origin of the lesion and the clinical course in selecting treatment alternatives. A historical review of the desmoplastic fibroma begins with the original description by MacFarlene in 1832 and its subsequent naming as desmoid tumor by Mueller in 1838, to both referring exclusively to the hard fibroma seen in the musculature of the anterior abdominal wall. In 1956, Paget correlated the histologic appearance of these fibromas with similar lesions in other anatomical sites, specifically the shoulder girdle and upper arm. 11 Jaffe in 1958 was the first to describe these extra-abdominal desmoids in bone and coined the term "desmoplastic fibroma. "12 He presented five cases involving the tibia, scapula, and femur, and in formulating the term desmoplastic fibroma indicated "the densely fibrous character of the lesional
tissue, which makes it resemble the familiar desmoid tumor of the abdominal wall." Griffith and Irby in 1965 reported what they concluded was the first case of a desmoplastic fibroma occurring in facial bones.P They described an 8year-old Caucasian girl with a palpable expansion of the left body of the mandible. The lesion was composed of mature, proliferating fibroblastic tissue found to erode and penetrate the cortical plate. Throughout the article the terms desmoid tumor and desmoplastic fibroma are used interchangeably. Since the publication of Jaffe's report, numerous small series and case reports have appeared, including work by Fisker and Philipsen,!" who identified 14 cases of desmoplastic fibroma of the mandible in addition to their own case report. The world literature was reviewed in 1978 by Freedman et al.,15 who reported a total of 25 cases. Interestingly, they Included only lesions clearly described as having arisen as primary central tumors of the jaw. Cases in which the tumor appeared to have arisen peripherally with subsequent secondary erosion of the jaw bones, such as that reported by Peede and Epker.!" were not included. As one follows the ensuing literature, the observation is made that lesions that arise centrally in bone are referred to as desmoplastic fibromas, whereas those that arise peripherally with possible bony invasion are termed aggressive fibromatoses. This division may have significant implications in reporting future cases and in assessing recurrence rates and appropriate treatment modalities for the two conditions. Shafer
535
ADDANTE AND LASKIN
defines a desmoplastic fibroma as a lesion of bone, including the jaws, which is histologically indistinguishable from aggressive fibromatoses or the extra-abdominal desrnoid.I Therefore, the true differentiation of these similar fibrous tumors and their treatment should be based on a review of the clinical behavior of the neoplasm and the radiographic findings, in addition to the gross and microscopic appearances. The consensus of various case reports indicates that clinically the desmoplastic fibroma (desmoid tumor) presents as a nontender, rapidly enlarging mass that causes little or no functional impairment. It is predominantly a disease of younger people, with a peak incidence in the second decade. I7 Attention is usually sought when facial asymmetry becomes apparent. Although rare, the majority have been reported in the mandible, with only four cases reported in the maxilla. IS Radiographically, they are radiolucent with welldefined sclerotic borders, some trabeculation, and expansile thin cortices. Some lesions have been reported with ill-defined borders suggesting malignancy. They may appear as unilocular or multilocular lesions. Grossly, the tumor is white or grayish-white in color and has a firm, almost rubbery consistency. It has a smooth, unencapsulated surface. Histologically, the neoplasm consists of fibrous tissue that varies throughout the lesion. Some areas show sparse fibroblasts in a field of dense intercellular collagen, whereas in other areas the fibroblasts may predominate and produce a whorled pattern.'? Nuclear atypia and mitotic activity are distinctly absent and serve to differentiate this lesion from a frank fibrosarcoma. Although morphologically benign, the lesion is infiltrative and can extend well beyond its clinical boundaries as this case illustrates. Accordingly, at Memorial Sloan-Kettering Cancer Center, desmoid tumors are regarded as low-grade fibrosarcornas.P The absence of osteoid differentiates this tumor from fibrous dysplasias. The lack of giant cells and foam cells helps to distinguish it from nonossifying fibromas. The most remarkable feature of this neoplasm is its tendency to recur, usually at the site of prior surgical excision. A total of 376 cases of extra-abdominal desmoids are reported with a recurrence rate of 6;3%.21 This figure, however, represents all extra-abdominal desmoids and tends to lump desmoplastic fibromas with aggressive fibromatoses. These entities may in fact have differing recurrence rates and there may be a role for thorough curettage with the central desmoplastic fibroma. For example, in the tumor reported by Fisker and Phil-
FIGURE 10. Photograph of the patient one year following definitive reconstruction.
ipsen in the anterior mandible.!" treatment consisted of thorough currettage with no recurrence after two years. The authors, however, recommend block resection in those cases where cortical bone is destroyed. The best therapy is elusive at present because of the relatively few reported cases and short follow-up studies. The experience at SioanKettering shows that excision with clear surgical margins offers the best chance for a recurrence-free course (Haidu SI, personal communication). Radiation therapy is not advised and may lead to sarcomatous transforrnation.P'P References I. Bastsakis JC: Tumors of the Head and Neck, 2nd ed. Baltimore. Williams & Wilkins, 1979 2. Shafer WC, Hine MK, Levy BM: A Textbook of Oral Pathology, 4th ed. Philadelphia, WB Saunders, 1983 3. Henefer EP, Bishop HC, Brown A: Juvenile fibromatosis with invasion of the mandible: report of two cases. Oral Surg 36:965, 1978 4. Peede LF Jr., Epker BN: Aggressive juvenile fibromatosis involving the mandible: surgical excision with immediate reconstruction. Oral Surg 43:651, 1977 5. Hinds EC, Kent IN, Fechner RE: Desmoplastic fibroma of the mandible: report ofa case. Oral Surg 27:271,1969 6. Laskin JL, Lebowitz MS, Baughman RA. et al: Clinicopathologic Conferences, Case 38, Part I. J Oral Maxillofac Surg 40:169, 1982 7. Laskin JL, Lebowitz MS, Baughman RA, et al: Clinicopathologic Conferences: Aneurysmal Bone Cyst of the Mandible, Case 38, Part II. J Oral Maxiliofac Surg 40:219, 1982 8. Allen PW: The fibromatoses: a clinicopathologic classification based on 140 cases. Part I. Am J Surg Pathol 1:255, 1977 9. Allen PW: The fibromatoses: a clinicopathologic classification based on 140 cases. Part II. Am J Surg Pathol 1:305, 1977 10. Pack GT, Ehrick HE: Neoplasms of the anterior abdominal wall with special consideration of desmoid tumors. Int Abst Surg 79:177, 1944 I I. Paget J: Fibronucleated tumor of the abdomen of 14 years growth; removal. Lancet 1:625, 1956
536 12. Jaffe HL: Tumors and Tumorous Conditions of the Bones and Joints. Philadelphia, Lea & Febiger, 1958, p 298 13. Griffith JG, Irby WB: Desmoplastic fibroma. Oral Surg 20:269, 1965 14. Fisker AV, Philips en HP: Desmoplastic fibroma of the jaw bones, Int J Oral Surg 5:285, 1976 15. Freedman PD, Cardo V, Kerpel S, et al: Desmoplastic fibroma (fibromatosis) of the jaw bones. Oral Surg 46:386, 1978 16. Peede LF, Epker BN: Aggressive juvenile fibromatosis involving the mandible: surgical excision with immediate reconstruction. Oral Surg 43:651, 1977 17. Sigura I: Desmoplastic fibroma: cast report and review of the literature. J Bone Joint Surg 58A:126, 1976
CASE 55
18. Eisen MZ, Butler HE: Desmoplastic fibroma of the maxilla: report of a case. J Am Med Assoc 108:608, 1984 19. Cunningham CD, Smith RO, Enriquez P, et al: Desmoplastic fibroma of the mandible: a case report. Ann Otol Rhinol Laryngo184:125,1975 20. Hajdu SI: Pathology of Soft Tissue Tumors. Philadelphia, Lea & Febiger, 1979, p 122 21. Hajdu SI: Pathology of Soft Tissue Tumors. Philadelphia, Lea & Febiger, 1979, p 128 22. Dahlin DC, Hoover NW: Desmoplastic fibroma of bone: report of two cases. J Am Med Assoc 188:685, 1964 23. Soule EH, Scanlon PW: Fibrosarcoma arising in an extraabdominal desmoid tumor: report of a case. Mayo Clin Proc 37:443, 1962