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Nerve sheath myxoma (neurothekeoma): A case involving the lip
Nerve sheath myxoma (neurothekeoma): A case involving the lip Maria R. Mason, M.D., Douglas R. Gnepp, M.D., and David R. Herbold, M.D., Ph.D., St. Louis, MO. DI‘PARTMENT
Ok
PATHOI.OGY.
ST.
LOUIS
UihIVERSITY
SCHOOI.
OF
MFDICINE
This case report describes an unusual benign neural tumor involving the lip. It appeared clinically gradually enlarging, painless growth arising on the lower lip. Microscopically, it was characterized whorls of spindle-shaped cells with abundant myxoid cytoplasm and stroma. (ORAL SURC. ORAL MED. ORAL PATHOL. 62185-186,
N
as a by
1986)
eurofibromas and neurilemmomas are the most common benign nerve sheath tumors occurring in a dermal or submucosal location. In 1969 Harkin and Reed’ described a rare neoplasm which they termed myxoma ofnerve sheath. The tumors were generally lobulated, occupied a major portion of the dermis, and usually extended into the subcutis. The tumor lobules were composed of spindle-shaped cells in an abundant mucoid matrix. In 1980 Gallagher and Helwig2 described fifty-three cases of a similar tumor of neural origin, which they termed neurothekeoma. Seventy-two percent of the lesions occurred in the central area of the face and on the arms and shoulders. Of those involving the face, fifteen out of
fifty-three (31.2%) were in the nasomalar, nasolabial, and lower forehead regions. In their discussion they mention the potential overlap between the neurothekeoma and the nerve sheath myxoma. Becauseof the histologic, ultrastructural, and histochemical similarity of these tumors, we prefer to consider both of these tumors as nerve sheath myxomas. A review of the literature reveals six previously reported cases of nerve sheath myxomas involving the oral cavity. M Two tumors involved the tongue, two the buccal mucosa, one the retromolar area, and one the palate. The purpose of this article is to report the first case
Fig. 1. Photomicrograph of the nerve sheath myxoma demonstrating a well-circumscribed mass (Hematoxylin and eosin stain. Magnification, X30.)
subcutaneous
185
188
Mason, Gnepp, and Herbold
Oral Surg. August.
Fig. 2. The neoplasm is composed of numerous nests containing spindle-shaped myxoid cytoplasm. (Hematoxylin and eosin stain. Magnification, X125.)
of this unusual lesion of neural origin involving the lip. CASE REPORT
The patient, a 32-year-old white woman, had noticed a gradually enlarging painless growth on the right corner of her lower lip for 15 years. No other lesions were present. She had no significant past medical or family history. The tumor was excised with a wide margin of normal skin and subcutaneous tissue. The patient is well 15 months after surgery, with no evidence of recurrence.
REFERENCES
I. Harkin 2. 3
DISCUSSION
The light microscopic appearance of the nerve sheath myxoma is characteristically described as nodular, with each nodule composed of spindleshaped or stellate cells in an abundant matrix of mucopolysaccharide, which usually stains positively for hyaluronic acid.2%5 Ultrastructural,3%7.8 histochemical,2s* and immunohistochemical* studies confirm the neuroectoderma1 nature of these lesions. Differential diagnosis consists of a neurofibroma,2*6-9a neural nevus,9 a pacinian neurofibroma,‘O*’ ’ and focal mucinosis.s
cells with abundant
The oral and dermal tumors have a benign clinical course and are best treated by surgical excision. In summary, this case report describes an unusual lesion of neural origin involving the lip.
HISTOPATHOLOGY
The specimen consisted of a 1 X 0.7 X 0.5 cm hard, tan, well-encapsulated nodule within an ellipse of skin and subcutaneous tissue. Microscopic sections stained with hematoxylin and eosin contained a well-circumscribed mass composed of nests and whorls of spindle-shaped cells with abundant myxoid cytoplasm (Figs. 1 and 2). The nests were separated by fibrous septa. Scattered chronic inflammatory cells were present.
1986
4. 5. 6.
1.
8.
9. IO.
1 I.
JC, Reed JJ: Tumors of the peripheral nervous system. second series, Fax. 3, Washington, D.C., 1969, Armed Forces Institute of Pathology, pp. 60-64. Gallagher RL. Helwig EB: Neurothekeoma-a benign cutaneous tumor of neural origin. Am J Clin Pathol 74: 759-76 I. 19x0. Si\t TC, Green GW: Benign nerve sheath myxoma: light and clcctron microscopic features of two cases. ORAL SURG ORAL MED ORAL. PATHOL 47: 441-444, 1979. Mincer HH, Spears KD: Nerve sheath myxoma in the tongue. ORAL SURG ORAL MED ORAL PATHOL 37: 428-430, 1974. Tomich CE: Oral focal mucinosis. ORAL SURC ORAL MED ORAL PATHOL 38: 7 14-724, 1974. Wright BA, Jackson D: Neural tumors of the oral cavity: a review of the spectrum of benign and malignant oral tumors of the oral cavity and jaws. ORAL SURG ORAI. MED ORAL PATHOL 49: 509-529, 1980. Webb JN: The histogenesis of nerve sheath myxoma: report of a case with electron microscopy. J Pathol 127: 35-37, 1979. AngervaIl L, Lars-Gunnar K, Haglid K: Dermal nerve sheath myxoma: a light and electron microscopic, histochcmical and immunohistochemical study. Cancer 53: 1752-1759. 1984. Abell MA, Hart WR, Olson JR: Tumors of the peripheral nervous system. Hum Pathol 1: 503-5.51, 1970. Toth BB,-Long WH. Pleasants JE: Central pacinian neurofibroma of the maxilla. ORAL SURG ORAL MED ORAL PATHOI. 39: 630-634, 1975. Prose PH, C;herardi GJ, Coblcnz A: Pacinian ncurotibroma. Arch Dermatol 76: 65-68. 1957.
Reprint
requrs1.s 10:
Dr. Douglas R. Gnepp The University Hospital Department of Pathology 1325 S. Grand Blvd. St. Louis, MO 63104
Ok
PATHOI.OGY.
ST.
LOUIS
UihIVERSITY
SCHOOI.
OF
MFDICINE
This case report describes an unusual benign neural tumor involving the lip. It appeared clinically gradually enlarging, painless growth arising on the lower lip. Microscopically, it was characterized whorls of spindle-shaped cells with abundant myxoid cytoplasm and stroma. (ORAL SURC. ORAL MED. ORAL PATHOL. 62185-186,
N
as a by
1986)
eurofibromas and neurilemmomas are the most common benign nerve sheath tumors occurring in a dermal or submucosal location. In 1969 Harkin and Reed’ described a rare neoplasm which they termed myxoma ofnerve sheath. The tumors were generally lobulated, occupied a major portion of the dermis, and usually extended into the subcutis. The tumor lobules were composed of spindle-shaped cells in an abundant mucoid matrix. In 1980 Gallagher and Helwig2 described fifty-three cases of a similar tumor of neural origin, which they termed neurothekeoma. Seventy-two percent of the lesions occurred in the central area of the face and on the arms and shoulders. Of those involving the face, fifteen out of
fifty-three (31.2%) were in the nasomalar, nasolabial, and lower forehead regions. In their discussion they mention the potential overlap between the neurothekeoma and the nerve sheath myxoma. Becauseof the histologic, ultrastructural, and histochemical similarity of these tumors, we prefer to consider both of these tumors as nerve sheath myxomas. A review of the literature reveals six previously reported cases of nerve sheath myxomas involving the oral cavity. M Two tumors involved the tongue, two the buccal mucosa, one the retromolar area, and one the palate. The purpose of this article is to report the first case
Fig. 1. Photomicrograph of the nerve sheath myxoma demonstrating a well-circumscribed mass (Hematoxylin and eosin stain. Magnification, X30.)
subcutaneous
185
188
Mason, Gnepp, and Herbold
Oral Surg. August.
Fig. 2. The neoplasm is composed of numerous nests containing spindle-shaped myxoid cytoplasm. (Hematoxylin and eosin stain. Magnification, X125.)
of this unusual lesion of neural origin involving the lip. CASE REPORT
The patient, a 32-year-old white woman, had noticed a gradually enlarging painless growth on the right corner of her lower lip for 15 years. No other lesions were present. She had no significant past medical or family history. The tumor was excised with a wide margin of normal skin and subcutaneous tissue. The patient is well 15 months after surgery, with no evidence of recurrence.
REFERENCES
I. Harkin 2. 3
DISCUSSION
The light microscopic appearance of the nerve sheath myxoma is characteristically described as nodular, with each nodule composed of spindleshaped or stellate cells in an abundant matrix of mucopolysaccharide, which usually stains positively for hyaluronic acid.2%5 Ultrastructural,3%7.8 histochemical,2s* and immunohistochemical* studies confirm the neuroectoderma1 nature of these lesions. Differential diagnosis consists of a neurofibroma,2*6-9a neural nevus,9 a pacinian neurofibroma,‘O*’ ’ and focal mucinosis.s
cells with abundant
The oral and dermal tumors have a benign clinical course and are best treated by surgical excision. In summary, this case report describes an unusual lesion of neural origin involving the lip.
HISTOPATHOLOGY
The specimen consisted of a 1 X 0.7 X 0.5 cm hard, tan, well-encapsulated nodule within an ellipse of skin and subcutaneous tissue. Microscopic sections stained with hematoxylin and eosin contained a well-circumscribed mass composed of nests and whorls of spindle-shaped cells with abundant myxoid cytoplasm (Figs. 1 and 2). The nests were separated by fibrous septa. Scattered chronic inflammatory cells were present.
1986
4. 5. 6.
1.
8.
9. IO.
1 I.
JC, Reed JJ: Tumors of the peripheral nervous system. second series, Fax. 3, Washington, D.C., 1969, Armed Forces Institute of Pathology, pp. 60-64. Gallagher RL. Helwig EB: Neurothekeoma-a benign cutaneous tumor of neural origin. Am J Clin Pathol 74: 759-76 I. 19x0. Si\t TC, Green GW: Benign nerve sheath myxoma: light and clcctron microscopic features of two cases. ORAL SURG ORAL MED ORAL. PATHOL 47: 441-444, 1979. Mincer HH, Spears KD: Nerve sheath myxoma in the tongue. ORAL SURG ORAL MED ORAL PATHOL 37: 428-430, 1974. Tomich CE: Oral focal mucinosis. ORAL SURC ORAL MED ORAL PATHOL 38: 7 14-724, 1974. Wright BA, Jackson D: Neural tumors of the oral cavity: a review of the spectrum of benign and malignant oral tumors of the oral cavity and jaws. ORAL SURG ORAI. MED ORAL PATHOL 49: 509-529, 1980. Webb JN: The histogenesis of nerve sheath myxoma: report of a case with electron microscopy. J Pathol 127: 35-37, 1979. AngervaIl L, Lars-Gunnar K, Haglid K: Dermal nerve sheath myxoma: a light and electron microscopic, histochcmical and immunohistochemical study. Cancer 53: 1752-1759. 1984. Abell MA, Hart WR, Olson JR: Tumors of the peripheral nervous system. Hum Pathol 1: 503-5.51, 1970. Toth BB,-Long WH. Pleasants JE: Central pacinian neurofibroma of the maxilla. ORAL SURG ORAL MED ORAL PATHOI. 39: 630-634, 1975. Prose PH, C;herardi GJ, Coblcnz A: Pacinian ncurotibroma. Arch Dermatol 76: 65-68. 1957.
Reprint
requrs1.s 10:
Dr. Douglas R. Gnepp The University Hospital Department of Pathology 1325 S. Grand Blvd. St. Louis, MO 63104