Transscleral Leiomyoma

Transscleral Leiomyoma

Transscleral Leiomyoma CAROL L. SHIELDS, MD,t JERRY A. SHIELDS, MD,t MICHAEL P. V ARENHORST, MD2 Abstract: A bluish-pink epibulbar lesion, which slow...

4MB Sizes 0 Downloads 62 Views

Transscleral Leiomyoma CAROL L. SHIELDS, MD,t JERRY A. SHIELDS, MD,t MICHAEL P. V ARENHORST, MD2

Abstract: A bluish-pink epibulbar lesion, which slowly enlarged over a period of 5 years, developed in a 31-year-old woman. The lesion initially resembled a staphyloma, based on the very thinned overlying sclera, but subsequent evaluation suggested that it was a solid mass. At the time of surgical removal, the mass appeared to have originated in the supraciliary region and to have eroded outward through the sclera. Histopathologically, the mass proved to be a leiomyoma. The authors propose theoretic possibilities to explain the location of this rare type of ocular smooth muscle tumor. Ophthalmology 1991; 98:84-87

The leiomyoma is a benign smooth muscle tumor that can develop in many parts of the body. It occurs in the female genital tract in over 95% of cases. l Histopathologically confirmed intraocular leiomyomas are rare and have been reported to occur in the iris, ciliary body, and choroid. 2 - l9 We report a unique case ofa leiomyoma in a 31year-old woman that apparently originated in the supraciliary region and eroded outward through the sclera, simulating an epibulbar mass. The histogenesis of a leiomyoma in this unusual location is uncertain. It could have arisen from strands of smooth muscle tissue in the supraciliary space, the muscularis layer of the anterior ciliary artery, or from ectopic smooth muscle within the sclera.

CASE REPORT A 31-year-old woman was noted in 1985 to have a "presumed staphyloma" temporally in her right eye. Her ophthalmologist elected to follow the lesion without treatment. Between 1985 and 1987, the lesion had acquired a dusky blue hue and enlarged by 2.5 mm in basal dimension and 2 mm in height. Orbital computed tomography (CT) performed elsewhere reported findings compatible with a staphyloma. In 1988, the lesion showed still further enlargement and the patient was referred to Originally received: April 27, 1990. Revision accepted: September 17, 1990. 'Ocular Oncology Service, Wills Eye Hospital, Thomas Jefferson University, Philadelphia. 2 Wesley Medical Center, Wichita.

the Ocular Oncology Service at Wills Eye Hospital for further evaluation. The patient had no significant past medical history and there was no history of ocular trauma. She was a mild myope with a refractive error of -1.00 - 1.25 X 180 in each eye. The corrected visual acuities were 6/6 in both eyes. The intraocular pressures were 11 mmHg in both eyes. The left eye was entirely normal. Results of right anterior segment examination showed a bluish-pink elevated mass in the epibulbar area just anterior to the insertion of the lateral rectus muscle (Fig 1). The mass measured approximately 7 X 7 mm in diameter and 3 mm in thickness and appeared to be covered by thin overlying sclera. There were no sentinel vessels. The remainder of the anterior segment was normal. The fundus of the affected right eye was normal, with no visible intraocular component to the epibulbar mass. Transillumination of the right globe showed normal findings with no increased transmission of light in the area of the episcleral lesion as one would see with a staphyloma. Intravenous fluorescein angiography demonstrated a lacy plexus of blood flow through the episcleral mass with late diffuse staining. Our differential diagnosis included epibulbar cavernous hemangioma, capillary hemangioma, hemangiopericytoma, or fibrous histiocytoma. We did not seriously consider the diagnosis of melanoma. Because of the documented enlargement over 3 years with compromise of the sclera, it was decided to resect the lesion. During surgery, the well-circumscribed mass was found to be located in the supraciliary region and to have eroded almost completely through the sclera. After removal of the mass, an 8 mm round, full-thickness scleral defect was present, exposing the underlying uveal tract (Fig 2). The defect was covered with a free scleral graft from an eye bank eye. The patient has done well clinically since the surgery.

Presented at the Annual Meeting of the Eastern Ophthalmic Pathology, Hilton Head, South Carolina, October 1989. Supported by the Ocular Oncology Fund and the Oncology Research Fund, Wills Eye Hospital, Philadelphia, and the Eye Tumor Research Foun· dation, Gladwyne, Pennsylvania.

PATHOLOGY

Reprint requests to Carol L. Shields, MD, Ocular Oncology Service, Wills Eye Hospital, Ninth and Walnut Sts, Philadelphia, PA 19107.

Gross examination of the resected specimen revealed an oval nonpigmented mass measuring 8.5 X 6.0 X 2.0

84

SHIELDS et al



TRANSSCLERAL LEIOMYOMA

mm. Microscopically, the highly vascular tumor was composed of spindle cells with slightly pleomorphic vesicular to hyperchromatic nuclei and abundant fibrillar eosinophilic cytoplasm (Figs 3, 4). The poorly cohesive tumor cells were arranged in whorls and abortive fascicles. There were numerous thin walled vessels of capillary caliber. Rare pigmented cells possibly representing uveal melanocytes were present within the tumor. A solitary nerve was noted in the periphery of the specimen. There were no mitoses. Immunohistochemical studies demonstrated immunoreactivity for muscle specific antigen (1 :4000, Enzo Laboratories) and smooth muscle actin (1 :4000, Sigma Laboratories) (Fig 5). Portions of the tumor stained for vimentin (1 :20, Dako Laboratories). The endothelial cells of the capillaries stained for factor VIII related antigen (1: 1000, Dako Laboratories). Tumor cells did not stain for S-1 00 (1: 1000, Dako Laboratories), leu 7 (1: 10, Becton, Dickinson Laboratories), or melanoma specific antigen (1: 1000, Enzo Laboratories). The final diagnosis was a highly vascular benign spindle cell tumor of smooth muscle origin (leiomyoma).

COMMENT Leiomyomas are benign smooth muscle tumors that occur in the distribution of smooth muscle tissue throughout the body. Approximately 95% ofleiomyomas are found in the female genital tract. 1 The remainder are scattered in various sites including skin (3%), gastrointestinal tract (1 %), bladder « 1%), and others « 1%).1 Systemic leiomyomas are much more common in women because most leiomyomas are found in the uterus. Several other types of systemic leiomyomas are found almost exclusively in women and these include intravenous leiomyomas, disseminated peritoneal leiomyomas, and vascular leiomyomas of the skin. 1 Leiomyomas have been reported to occur occasionally in the eye l- 19 and in the orbit. 20- 22 Intraocular leiomyomas have been found in the iris, ciliary body, and choroid. In these cases they are believed to arise from the smooth muscle in the iris sphincter and dilator muscle, ciliary body muscle, blood vessel-associated smooth muscle or pericytes, or possible heterotopic smooth muscle cells in the choroid. 2,19,21 One recently reported case seemed to have arisen in the supraciliary region. 17 It is believed that some systemic leiomyomas, especially those found exclusively in women, are related to chronic hormonal stimulation. Contraceptive medications and pregnancy have been shown to stimulate the growth of these tumors and cessation of the hormonal states has allowed regression of the lesions. 1 Likewise, leiomyomas of the ciliary body have been found to have an unusually high incidence in young women. 17 Of the cases reported in the literature, 15 of 16 patients with ciliary body leiomyomas were women, most of whom were in their reproductive years. 17 This female preponderance of intraocular leiomyomas has been emphasized by Shields and associates.17 The patient we present is a 31-year-old

woman in whom a leiomyoma developed 4 years after her first pregnancy, and the lesion grew during her second pregnancy. Whether this leiomyoma is at all related to the pregnancy or hormonal changes is unknown. It has been postulated in a previously reported case of a choroidal leiomyoma that the tumor arose from either vessel-associated pericytes or smooth muscle. 19 In that case, the choroidal leiomyoma eroded through the sclera posteriorly. Histopathologically, the tumor was well circumscribed with sharp borders and exhibited no infiltration into the adjacent choroid, although the tumor did erode the overlying thinned sclera. There was a very prominent vascular component. The case we report resembles that vascular choroidal leiomyoma in many ways. 19 Our case also caused scleral erosion, was well circumscribed, and was very vascular with many thin-walled capillaries. It is interesting that both our case and the case mentioned previouslyl9 were diagnosed as presumed vascular leiomyoma and both caused scleral erosion. Possibly this occurred as these benign tumors grew along the course of their blood vessels as they traversed the sclera. It is difficult to be certain whether the tumor in our patient originated from the supraciliary tissue or within the sclera. It had eroded through the sclera, leaving only a few fibers remaining. The tumor was just anterior to the lateral rectus muscle insertion where the anterior ciliary vessels perforate the sclera. Possibly this leiomyoma arose from the intrascleral portion or the supraciliary portion of the anterior ciliary artery (muscularis layer or pericytes). It also is possible that it could have arisen from intrascleral heterotopic smooth muscle.23 The supraciliary location of intraocular leiomyomas in young women is intriguing. We recently reported a supraciliary leiomyoma in an ll-year-old girl. 17 The case reported here in a 31-year-old woman was in a supraciliary location. We have recently resected a similar supraciliary leiomyoma in a 20-year-old woman. The supraciliary location, seen in three consecutive cases in our experience, is a feature quite unlike any other intraocular tumor. The ophthalmologist should consider a leiomyoma in the differential diagnosis of an amelanotic ciliary body mass in a young woman. Systemic leiomyomas are generally derived from mesodermal tissue that differentiates into smooth muscle. Intraocular leiomyomas, however, are slightly different. They can be derived from mesoderm or mesectoderm. The mesodermal structures in the orbit are believed by some to include orbital rectus muscles and orbital blood vessels.2 4 The smooth muscle of the ciliary body and choroid originates from mesectoderm (neural crest cells that differentiate into myogenic tissue). Tumors arising from this tissue have been called mesectodermalleiomyomas. 6 It is postulated that the neural features of these tumors can be explained on the basis of the derivation of the ciliary body muscle from neural crest mesectoderm. The tumor that we report did not possess striking neural features and we prefer not to call it a mesectodermal leiomyoma. Clinically, the intraocular leiomyoma should be differentiated from amelanotic malignant melanoma and other more rare amelanotic uveal tumors. Histopathologically, 85

OPHTHALMOLOGY



JANUARY 1991



VOLUME 98



NUMBER 1

Fig 1. Top left, bluish-pink ectatic mass in the temporal sclera of the right eye. Fig 2. Center left, intraoperative photograph demonstrates the vascular tumor (open arrow) being peeled from the normal underlying uvea (closed arrow). Fig 3. Bottom left, microscopically, the tumor was highly vascular and composed of spindle cells and numerous thinned, walled capillaries (hematoxylin-eosin; original magnification, X 100). Fig 4. Top right, high-power microscopy demonstrates loosely cohesive spindle cells with round-to-oval nuclei (hematoxylin-eosin; original magnification, X250). Fig 5. Bottom right, immunohistochemical staining for smooth muscle actin demonstrates positivity as seen by the brown staining of the spindle cells (smooth muscle actin; original magnification, X 100, I :4000 dilution, Sigma Laboratories).

the leiomyoma may resemble any uveal "spindle cell" tumor including amelanotic spindle cell melanoma, amelanotic nevus, neurofibroma, or neurilemoma. Immunohistochemistry and electron microscopy generally are necessary to establish a definitive diagnosis.

REFERENCES 1. Enzinger FM, Weiss SW. Soft Tissue Tumors. St. Louis: CV Mosby, 1983; 281-97. 2. Green WR. The uveal tract. In: Spencer WH, ed. Ophthalmic Pathology: An Atlas and Textbook. Vol. 3. Philadelphia: WB Saunders 1986; 1601-23.

86

3. Blodi FC. Leiomyoma of the ciliary body. Am J Ophthalmol1950; 33: 939-42. 4. Dunbar JC. Leiomyoma of the ciliary body. Report of a case exhibiting a significant uptake of radioactive phosphorus. Am J Ophthalmol1956; 42:204-7. 5. Meyer SL, Fine BS, Font RL, Zimmerman LE. Leiomyoma of the ciliary body: electron microscopic verification. Am J Ophthalmol 1968; 66: 1061-8. 6. Jakobiec FA, Font RL, Tso MOM, Zimmerman LE. Mesectodermal leiomyoma of the ciliary body. A tumor of presumed neural crest origin. Cancer 1'977; 39:2102-13. 7. Lowe RF, Greer CH. Leiomyoma of the ciliary body: a clinico-pathological case report. Br J Ophthalmol1970; 54:383-7. 8. Vogel M, Spitznas M, Waubke TN. Leiomyoma of the ciliary body. Albrecht Von Graefes Arch Klin Exp Ophthalmol 1978; 209:89-98. 9. Jakobiec FA, Iwamoto T. Mesectodermal leiomyoma of the ciliary body associated with a nevus. Arch Ophthalmol1978; 96:692-5.

SHIELDS et al



TRANSSCLERAL LEIOMYOMA

10. Croxatto JO, Malbran ES. Unusual ciliary body tumor: mesectodermal leiomyoma. Ophthalmology 1982; 89:1208-12. 11. Orsoni JG, Daicker B, Piccolino FC. Mesectodermal leiomyoma of the ciliary body extending into the anterior chamber. Ophthalmologica 1985; 191:127-9. 12. Takagi T, Ueno Y, Matsuya N. Mesectodermal leiomyoma of the ciliary body: an ultrastructural study. Arch Ophthalmol1985; 103:1711-14. 13. Calmettes L, DeodaUi F, Bec P. Leiomyome du corps ciliaire. Bull Soc Ophthalmol Fr 1961; 74:158-67. 14. Gloor BP, Daicker B, Gafner F. Leiomyom des Ziliarkarpers-Durch Fehldiagnose auf ungewahnliche weise erfolgreich operiert. Klin Monatsbl Augneheilkd 1979; 175:760-6. 15. Sautter H, Bake WV, Domarus D, Demeler U. Leiomyom des Ziliarkarpers. Klinischer, fluoreszenzangiographischer und histologischer Befundbericht. Klin Monatsbl Augenheilkd 1979; 175:704-10. 16. Bonamour MM, Bonnet JL, Jambon M. Leiomyome du corps ciliare. Quelques considerations propos du diagnostic et du traitement des tumeurs ben ignes de I'iris et du corps ciliare. Bull Soc Ophthalmol Fr 1957; 57:482-5.

a

17. Shields JA, Shields CL, Eagle RC Jr. Mesectodermal leiomyoma of the ciliary body managed by partial lamellar iridocyclochloroidectomy. Ophthalmology 1989; 96: 1369-76. 18. White V, Stevenson K, Garner A, Hungerford J. Mesectodermalleiomyoma of the ciliary body: case report. Br J Ophthalmol 1989; 73: 12-8. 19. Jakobiec FA, Witschel H, Zimmerman LE: Choroidal leiomyoma of vascular origin. Am J Ophthalmol 1976; 82:205-12. 20. Jakobiec FA, Font RL. Orbit. In: Spencer WH, ed. Ophthalmic Pathology: An Atlas and Textbook. vol. 3. Philadelphia: WB Saunders, 1986; 2584-7. 21. Shields JA. Diagnosis and Management of Orbital Tumors. Philadelphia: WB Saunders, 1989; 252-5. 22. Sanborn GF, Valenzuela RE, Green WR. Leiomyoma of the orbit. Am J Ophthalmol1979; 87:371-5. 23. Daicker B. Heterope glaUe Muskulatur in der Aderhaut. Klin Monatsbl Augenheilkd 1983; 183:208-10. 24. Jakobiec FA, Tannenbaum M. Embryologic perspectives on the fine structure of orbital tumors. In: Jones IS, Jakobiec FA. Diseases of the Orbit. Hagerstown, MD: Harper & Row, 1979; 172-85.

87