Intraoral inflammatory pseudotumor

Intraoral inflammatory pseudotumor Philip David Earl, BDS, FDS, RCS, MBBS, FRCSa John Christopher Lowry, MBChB, BDS, FDS, RCS, FRCSb and Philip Sloan, BDS, PhD, MRC,Path.,C Lancashire and Manchester, U.K. BLAlCKBURN

ROYAL

INFIRMARY

AND UNIVERSITY

OF MANCHESTER

DENTAL

SCHOOL

A case of an intraoral inflammatory pseudotumor is described. Although this lesion has been reported to occur in the oral cavity, no cases have been documented in the literature. Difficulties were encountered in arriving at a diagnosis in a patient with a condition in the mandible. (ORAL SURC ORAL MED ORAL PATHIDL 1993;76:27943)

The inflammatory pseudotumor appears clinically as a rapidly growing tumor, but histologically it is composed entirely of inflammatory tissue. Described by Enzinger and Weiss’ and Rosai, it has been reported in the vagina,3 bladder,3-5 and larynx’ and is said to occur in the oral cavity’ although no reports have been found in the literature. The cause is unclear, but it seems likely that the stimulus is a chronic irritant that eventually prodlucesa dramatic progression of the inflammatory response with rapid tissue proliferation. CASE REPORT

A 44-year-old white man was referred to our department with progressive pain and swelling at the right mandibular angle related to the partially erupted lower right third molar. Examination revealed a firm buccal and submandibular swelling with tender submandibular lymphadenopathy. Mouth opening was limited interincisally to 25 mm. Intraorally the lower third molar was submergedin a massof proliferating tissue. Full blood count showed a granulocytosis. Radiographs indicated vertical impaction of the involved third molar and the proliferative soft tissue was also visible on the film (Fig. 1). Three days later the soft tissue had proliferated to reach the lower first molar and tuberosity. Arrangements were made for an examination with the patient under general anesthetic and for a biopsy of the soft tissue mass,which appearedto be malignant. Intubation was difficult becauseof the trismus. The histologic report was inconclusive, thus a repeat was advised. Sevendays later the swelling was larger, and the trismus was worse. There was further ti.ssue proliferation and regionallymphadenopathy.Computerizedtomographyscan demonstrated a #softtissue swelling that involved the manaRegistrar,Departmentof Oral and Maxillofacial

Surgery, Black-

burn R.oyal Infirmary.

bConsaltant,Department of Oral and Maxillofacial Surgery, BlackburnRoyal infirmary. “Senior Lecturer, Department of Oral Pathology, Manchester Dental School. Copyright @ 1993 by Mosby-Year Book, Inc. 0030-4220/93/$1.00 + .lO 7/12/42286

University

of

dible extending from the angle to the midline with no bony involvement of the pterygoid plates (Fig. 2). The appearanceswere consistent with either infection or soft tissue tumor. An autoantibody screen and immunoelectrophoresis showed no abnormality. The trismus had intensified on readmission for a secondbiopsy. Intubation proved impossible, and the biopsy was therefore performed with the patient under local anesthetic and sedation. The culture results on the tissue were negative, and histologic appearanceswere very similar to those of the previous biopsy that could not differentiate betweenneoplasiaor reactive change. The patient was admitted once more for radical curettage of th,e tissue and extraction of the lower right second and third molars. Slowly thereafter the proliferative tissue regressedalbeit with considerable fibrosis and granulation tissue production that spontaneously resolved. The histologic findings onceagain suggestedflorid chronic inflammation with no evidence of a malignant condition. The large number of plasma cells and whorled pattern of fibrossisraised the possibility of an inflammatory pseudotumour. The appearanceswere similar in all specimens.The tissue was composedof loose arrays of plump spindle cells in a fibromyxoid stroma that contained numerous inflammatory cells. Morphsologically the spindle cells resembled fibroblasts, and some were bipolar in shape. No atypical mitatic figures were identified, and nuclear pleomorphism was absent. Toward the epithelial surface, the cells were loosely arranged w’hereasin deepertissueslarge interlacing fascicles (Fig. 3) were present. Lymphocytic cells were scattered throughout the tissue and in places were densely packed together forming sheets (Figs. 4 and 5). Smaller numbers of plasma cells were also present. Immunoperoxidase staining was undertaken for the following: vimentin; desmin; alphat smooth muscle actin; low and high molecular weight cytokeratins and SlOO (to assist in thle identification of the spindle cells); common leukocyte antigen; kappa; lambda light chains; UCLA 1 T cell; pan B cell; and MAC 3 (to characterize the lymphocytic component). Spindle cell cytoplasm stained strongly for vimentin and was negative for desmin, cytokeratins, and S 100.There was variable expression of alpha1 smooth muscle actin. Markers for lymphocytic cells revealed a mixed population 279

280

Earl, Lowry, and Sloan

ORAL SURGERY ORAL MEDICINE ORAL PATHOLOGY September 1993

Fig. 1. Panoramic radiograph taken on presentation shows proliferative third molar.

soft tissue enguifing lower right

Fig. 2. CT scan shows soft tissue adjacent to but not invading mandible. with approximately equal numbers of cells stained for kappa and lambda light chains. Cells of macrophage lineage were scattered throughout the lesion. The polytypic nature of the lymphocytic component was consistent with an inflammatory process, and overall the features were those of an inflammatory pseudotumor. Over the next few months, the patient’s mouth opening was severely restricted as a result of a profound fibrosis around the operative site. A further computerized tomog-

raphy scan bad appearances consistent with chronic inftammation. A diagnosis of postinfective fibrosis was made, and the patient was readmitted for coronoidectomy and release of fibrosis by section of the pterygomasseteric sling, after minimal improvement with mandibular manipulation. Endotracheal intubation was again difficult but ultimately successful after the use of a fiberoptic endoscope, and there was marked improvement after surgery. Healing took place by secondary intention as a result of wound

Earl, Lowry, and Sloan

ORAL SURGERY ‘ORAL MEDICINE ORAL PATHOLOGY Volume 76, Number 3

281

Fig. 3. Photomicrograph shows predominant appearanceof interlacing fascicles of fibroblastic CIells. (Original magnification ~25.)

Fig. 4. Inflammatory area of pseudotumor shows intense lymphohistiocystic infiltration. (Origi nal magnification :X55.) breakdclwn with an inevitable partial relapse of trismus. Histolo gic examination of the excised tissue showed no recurrenc:e of pseudotumor. With physiotherapy and exercises, tl re opening once again improved. Two years after presentation the patient is well, has regained,all the 12 kg of weight lost dnring his illness, and has no sign of recurrent proliferative tissue. Fibrosis persists

with limitation of opening to 25 mm btIt nevertheless the patient has few complaints. DISCUSSION

Inflammatory pseudotumors have been reporter cl in the urinary bladder and genitourina ry tract after instrumentation. According to Enzin ger and Wei .SS,l

282

Earl, Lowry, and Sloan

ORAL SURGERY ORAL MEDICINE ORAL PATHOLOGY September 1993

Fig. 5. Plump and slender fibroblastic cells possessingelongated cytoplasmic processeswith scattered inflammatory cells. (Original magnification X 125.)

inflammatory pseudotumors may also occur in the vagina, lung, and oral cavity. There are no reports of inflammatory pseudotumors in the jaws although Rosai records cases that involve the alveolar process. However, the features illustrated by Rosai are, in our view, more consistent with fibrous hyperplasia. The occurrence of inflammatory pseudotumors in the orbit is well documented6, 7 and extension into the maxillary antrum is reported.* However, the orbital inflammatory pseudotumor is distinctive and may include both xanthomatous and granulomatous components, which are lacking in our oral case. In reaching the diagnosis it was important to exclude spindle cell neoplasms such as polypoid carcinoma9 by desmin staining and melanoma or peripheral nerve tumor by S 100 staining. The cellular morphology and vimentin staining was consistent with fibroblastic differentiation. The characteristic herringbone pattern of fibrosarcoma and storiform pattern of malignant fibrous histiocytoma were absent. The morphology and arrangement of the fibroblastic cells and dense inflammatory component, together with rapid growth and clinical behavior were the principal features that led to the diagnosis of inflammatory pseudotumor in this case. Inflammatory lesions are usually treated less radically than neoplasms with little excision of normal tissue. Healing takes place with a combination of fibrosis and resolution of normal tissue as the inflam-

matory process resolves. In a lesion such as the inflammatory pseudotumor the inflammatory process is dramatic, and the fibrosis is consequently intense. Hnthe case reported, the postsurgical rehabilitation proved to be exceedingly difficult. As the fibrosis was not confined to the superficial layers, contraction of deeper tissues would probably have rendered the use of a split skin graft or free flap ineffective. This was considered as a means of improving mandibular opening. A further complication of fibrous contracture was intubation difficulty. On three occasions surgical procedures were delayed or postponed because of failure to establish intubation even after attempts by experienced anesthetists. CONCLUSLON The inflammatory pseudotumor is a very rare lesion particularly in the oral cavity. Both clinically and histologically it presents diagnostic difficulties and can mimic a malignant tumor. Long-term complications of fibrosis, which included limitation of mandibular opening, were apparent in this case, and these would appear difficult to avoid. REFERENCES 1. Enzinger FM, Weiss SW. Soft tissue tumors, 2nd ed. St. Louis: CV Mosby, 1988:414-5. 2. Rosai J. Ackerman’s surgical pathology, 7th ed. St. Louis: CV Mosby, 1989:174-5.

ORAL SURGERY ORAL MEDICINE ORAL PATHOLOGY Volume 76, Number 3 3. Nochomovitz LE, Orenstein JM. Inflammatory pseudotumor of the urinary bladder: possible relationship to nodular fasciitis-two case reports, cytologic observations, and ultrastructural observations. Am J Surg Path01 1985;9:366. 4. Ro JY, Ayola ,4G, Ordorey NG, et al. Pseudosarcomatous fibromyxoid tumor of the urinary bladder. Am J Clin Path01 1986;86:583. 5. Young RH, Scully RE. Pseudosarcomatous lesions of the urinary bladder, prostate gland, and urethra: a report of three cases and review of the literature. Arch Path01 Lab Med 1987;34:354-8. 6. Frohman LP, Kupersmith MJ, Lang EJ, et al. Intercranial extension and bone destruction in orbital pseudotumor. Arch Ophthalmol 1986;104:380-4. 7. Lee WR, McGhee CNJ. Pseudotumors in the orbit. Recent Advances in Histopathology, 1989;14:123-37.

Earl, Lowry, and Sloan

8. Eshagian J, Anderson RL. Sinus involvement in inflammatory orbital pseudotumor. Arch Ophthalmol 1981;99:627-30. 9. Middlehurst RJ, Blackburn CW, Sloan P. Spindle cell carcinoma: a case report. Br J Oral Maxillofac Surg 1990;28: 111-3. Reprint requests: Philip David Earl 16 Allesley Close Westhoughton Bolton Lancashire BL5 3DW United Kingdom

CALL FOR REVIEW ARTICLES The January 1993 issue of ORAL SURGERY, ORAL MEDICINE, ORAL PATBOLOGY contained an Editorial by the Journal’s new Editor in Chief, Larry J. Paterson, that called for a Review Article to appear in each issue. These Review Articles should be designed to review the current status of matters that are important to the practitioner. These articles should contain current developments, changing trends, as well as reaffirmation of current techniques and policies. Please consider submitting your article to appear as a Review Article. Inforrnation in each issue of ORAL SURGERY, ORAL MEDICINE, ORAL PATHOLOGY.

for authors appears

We look forward to hearing from you. I

283

I