Int. J. Oral Surg. 1978: 7: 123-125 (Key words: myoblastorna; surgery, ora!; palate)
Granular cell myoblastoma of the soft palate Report of a case NICHOLAS C. CHOUKASl, EUGENE W. SEKLECKJ2, PATRICK D. TOTOl AND MARSHALL H. SHORT3 lDepartment of Oral and Maxillofacial Surgery, 2Departmellt of Oral Pathology, Maywood and 3Loretto Hospital, Chicago, Illinois, U.S.A.
Report of a case of granular cell myoblastoma of the soft palate. This is the first report of such a lesion in the soft palate and serves to support the muscle origin of granular cell lesions.
(Received for publication 8 August, accepted 30 November 1976)
The granular cell myobJastoma is a very uncommon soft tissue tumor that can arise in almost any location. There is an 87 % predilection for the tongue in oral lesions with no sex predominance and it occurs at an average age of about 40 years 15 • It is generally benign with a 3 % malignant potentialS, 10,13. First reported by ABRIKOSSOFF in 1926 1, it has since then been thoroughly studied. A histochemical study by TOTO, CHOUKAS & RESTARSKI16, revealed this lesion to be a "proliferative tumor of rest cells which differentiate into fibroblasts. Also, degenerative muscle and fibrous connective tissue contribute to the morphology of the tumor." Others feel it may be of neurogenic or Schwann cell origin or a multicentric histogenesis from muscle and nerve cells2,6,7,11,14, Excellent reviews of the literature have
been done 3,12, In one series 3 278 cases of oral granular cell myoblastoma from 18541967 were covered. Up to the present there are only three cases reported on the hard palate 4. 5 .9• To our knowledge, this is the first reported case on the soft palate.
Case Report The patient was a 48-year-old, black female. well nourished and in no acute distress, who presented herself to our institution for dental treatment in September 1975. An oral surgical evaluation was called for because of a swelling noticed in the right soft palate. The patient had noticed it about 6 months previously and stated it had not enlarged. Past history was negative except for a total hysterectomy for menorrhagia 16 years prior to admission. Family history was negative. Review of systems was essentially negative. She denied allergies and regular use of any medication. ENT exam revealed a 2 X 2 cm slightly elevated, amber-yellowish, submucous
CHOUKAS, SEKLECK1, TOTO AND SHORT
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Fig. 1. Photomicrograph of the lesion showing the granular nature of the cells.
Discussion In the oral cavity it is interesting that the granular cell lesion has a high incidence in tongue muscle and understandably was first described as a myoblastoma. The soft palate, also a muscular organ, should be a potential site for such a lesion. This first report of such a lesion in the soft palate would serve to support the muscle origin of granular cell lesions.
References 1. ABRIKOSSOFF, A.: Uber Myome. ausgehend
tumescence of the right soft palate without displacement of the uvula. It was soft and nontender. There was no lymphadenopathy. The initial impression was a mixed-cell tumor. In general anesthesia, the tumor mass was delineated by sharp and blunt dissection and delivered in toto. The tumor was not well encapsulated and resembled somewhat a poorly defined lipoma.
Results Gross Pathology Report Specimen consisted of an 18 X 9 ffim white, partially encapsulated tissue mass. It was serially sectioned to show all of the lateral resection lines and was entirely submitted. The microscopical examination revealed the presence of a tumor beneath the mucosa, and to an extent, surrounding the salivary gland tissue (Fig. 1). The tumor is composed of a uniform collection of large, eosinophilic granUlar cells with small, benign appearing nuclei. The t:ells do not appear to be encapsulated, but appear to be spreading out diffusely through the connective tissue, and they extend to the lateral and deep surgical resection lines. Striated muscle is seen frequently adjacent to the tumor cells. There is no evidence of malignancy. The diagnosis was granular cell tumor (myoblastoma), clinically from the soft palate.
8. 9. 10.
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E. A. & AZAR, H. A.: Multiple granular cell tumors ("myoblastomas"). Case report with electron microscopic ob~ervations and review of the literature. Cancer 1967: 20: 2032. 13. Ross, R. C, MrLLER, R. T. & FOOTE, F. W., Jr.: Malignant granular cell myoblastoma. Cancer 1952: 5: 1 [2. 14. SOBEL, H. J. & CHURG, J.: Granular cells and granular cell lesions. Arch. Patllol. 1964: 77: 132. 15. TIEKE. W. R.: Oral pathology. McGrawHill 1965, p. 576. MOSCOVIC,
TOTO, P., CHOUKAS, N. & RESTARSKI, J.: Granular cell fibroblastoma. Oral Surg. Oral Med. Oral Pathal. 1962: 15: 450-453.
Address: Nicho!as C. Chouktls Department 0/ Oral and lV/axillo/acia! SurgeI')' Loyola University School 0/ Delltistry :>'160 Soutlz First Avenue Maywood, 1llinois 60153 U.S.A.