RHABDOMYOMA O F T H E ORBIT DANIEL M. KNOWLES II, M.D.,
AND FREDERICK A. JAKOBIEC,
M.D.
New York, New York 1
Henderson has questioned the existence of orbital adult-type rhabdomyoma, a be nign tumor of well-differentiated striated mjjgcle; his comprehensive and critical re view of orbital tumors failed to uncover a single example at the Mayo Clinic or a welldocumented published case. The most recent report of orbital rhabdomyoma by Nath and associates2 is not unequivocal and prompts reservations, as do earlier case reports3"6 that are poorly characterized and appear to be inflammatory pseudotumors involving the extraocular muscles or tumors other than rhabdomyoma. The present case of orbital rhabdomyoma is to our knowledge the first to be documented. CASE REPORT
In July 1938, an 8-year-old white boy had a three-month history of an asymptomatic, gradually enlarging mass in the nasal aspect of his left upper eyelid. The mass was firm, circumscribed, nontender, and nonfluctuant, measuring 3 x 2 cm (Fig. 1). It extended from the inner canthus upward and backward, passing behind the orbital margin. It was not adherent to the overlying skin, but was not freely movable either. Visual acuity was 20/20 bilaterally and extraocular motility was undisturbed. The clinical diagnosis was hemangioma. At surgery, an encapsulated and multilobulated mass was found, arising from the anterior aspect of the belly of the medial rectus muscle. It extended superiorly to incorporate the trochlea. The mass and involved trochlea were locally excised. Before the patient left the hospital, his mother noted a small, red carneous tag of tissue near the semilunar fold. This gradually increased in size, until four months later when the patient returned with a pea-sized lesion overlying the insertion of the medial rectus muscle (Fig. 2). This neoplasm was interpreted as a recurrent rhabdomyosarcoma, and an orbital exenteration was performed. The patient was alive and free of disease 27 years later (1965) but has since been lost to follow-up. From the Departments of Pathology (Dr. Knowles) and Ophthalmology (Dr. Jakobiec), College of Physicians and Surgeons, Columbia Uni versity, New York, New York. Reprint requests to Daniel M. Knowles II, M.D., Department of Pathology, College of Physicians and Surgeons of Columbia University, 630 W. 168 St., New York, NY 10032.
RESULTS
Pathologic findings—Grossly, the lesioi was described as a firm, bosselated, grayish yellow, encapsulated mass, 3.3 X 2.0 X l.i cm that involved the trochlea ( Fig. 3 ). Micro scopically, the tumor was encapsulatec but subdivided by thick fibrous sept; into distinct lobules (Figs. 4 and 5) an< composed of compactly arranged, large round to polygonal cells with abundant gran ular, acidophilic cytoplasm (Fig. 6). Higl magnification disclosed that the granular na ture of the cytoplasm was due to the pres ence of numerous myofibrils oriented hap hazardly in three dimensions. Degenerating tumor cells displayed brilliant fuchsinophili; due to compaction of the myofibrils in thi shrunken cytoplasm (Fig. 7). The myo fibrillar nature of the cytoplasm of the cell: was well demonstrated by the trichrom< stain. Each cell generally had a single, eccen trically placed, large, vesicular nucleus witl
Fig. 1 (Knowles and Jakobiec). The tumor pre sented initially as a swelling in the upper nasal quadrant of the left orbit. No extraocular motility disturbances were noted. 1011
1012
AMERICAN JOURNAL OF OPHTHALMOLOGY
Fig. 2 (Knowles and Jakobiec). Four months later the tumor recurred at the insertion of the medial rectus muscle, presumably due to incomplete local excision initially. a prominent, central, basophilic nucleolus ( F i g . 6 ) . Some cells had centrally placed nuclei or more than one nucleus. Many of the cells contained much glycogen, causing an apparent strand-like separation of the cyto plasm from the sarcolemma, suggesting large empty spaces with the formation of spider
DECEMBER, 1975
cells (Fig. 8 ) . Sedulous microscopic exam ination showed cells with well-organized cross striations (Fig. 9 ) . T h e r e were m;:ny cells with multiple, acidophilic, rod-like struc tures, so-called "myosin crystals" ( F i g . 10). Comment—We discovered this case of adult-type rhabdomyoma during our review of rhabdomyosarcomas on file here. The case was misdiagnosed as a rhabdomyosarcoma in 1938, before the diagnostic criteria for rhab domyosarcoma and rhabdomyoma had been clearly established. Jones, Reese, and Kraut 7 described this patient in a series of orbital rhabdomyosarcoma cases (Case 14) in 1966.
DISCUSSION
Rhabdomyomas most commonly occur in the hf*art« nt
AND FREDERICK A. JAKOBIEC,
M.D.
New York, New York 1
Henderson has questioned the existence of orbital adult-type rhabdomyoma, a be nign tumor of well-differentiated striated mjjgcle; his comprehensive and critical re view of orbital tumors failed to uncover a single example at the Mayo Clinic or a welldocumented published case. The most recent report of orbital rhabdomyoma by Nath and associates2 is not unequivocal and prompts reservations, as do earlier case reports3"6 that are poorly characterized and appear to be inflammatory pseudotumors involving the extraocular muscles or tumors other than rhabdomyoma. The present case of orbital rhabdomyoma is to our knowledge the first to be documented. CASE REPORT
In July 1938, an 8-year-old white boy had a three-month history of an asymptomatic, gradually enlarging mass in the nasal aspect of his left upper eyelid. The mass was firm, circumscribed, nontender, and nonfluctuant, measuring 3 x 2 cm (Fig. 1). It extended from the inner canthus upward and backward, passing behind the orbital margin. It was not adherent to the overlying skin, but was not freely movable either. Visual acuity was 20/20 bilaterally and extraocular motility was undisturbed. The clinical diagnosis was hemangioma. At surgery, an encapsulated and multilobulated mass was found, arising from the anterior aspect of the belly of the medial rectus muscle. It extended superiorly to incorporate the trochlea. The mass and involved trochlea were locally excised. Before the patient left the hospital, his mother noted a small, red carneous tag of tissue near the semilunar fold. This gradually increased in size, until four months later when the patient returned with a pea-sized lesion overlying the insertion of the medial rectus muscle (Fig. 2). This neoplasm was interpreted as a recurrent rhabdomyosarcoma, and an orbital exenteration was performed. The patient was alive and free of disease 27 years later (1965) but has since been lost to follow-up. From the Departments of Pathology (Dr. Knowles) and Ophthalmology (Dr. Jakobiec), College of Physicians and Surgeons, Columbia Uni versity, New York, New York. Reprint requests to Daniel M. Knowles II, M.D., Department of Pathology, College of Physicians and Surgeons of Columbia University, 630 W. 168 St., New York, NY 10032.
RESULTS
Pathologic findings—Grossly, the lesioi was described as a firm, bosselated, grayish yellow, encapsulated mass, 3.3 X 2.0 X l.i cm that involved the trochlea ( Fig. 3 ). Micro scopically, the tumor was encapsulatec but subdivided by thick fibrous sept; into distinct lobules (Figs. 4 and 5) an< composed of compactly arranged, large round to polygonal cells with abundant gran ular, acidophilic cytoplasm (Fig. 6). Higl magnification disclosed that the granular na ture of the cytoplasm was due to the pres ence of numerous myofibrils oriented hap hazardly in three dimensions. Degenerating tumor cells displayed brilliant fuchsinophili; due to compaction of the myofibrils in thi shrunken cytoplasm (Fig. 7). The myo fibrillar nature of the cytoplasm of the cell: was well demonstrated by the trichrom< stain. Each cell generally had a single, eccen trically placed, large, vesicular nucleus witl
Fig. 1 (Knowles and Jakobiec). The tumor pre sented initially as a swelling in the upper nasal quadrant of the left orbit. No extraocular motility disturbances were noted. 1011
1012
AMERICAN JOURNAL OF OPHTHALMOLOGY
Fig. 2 (Knowles and Jakobiec). Four months later the tumor recurred at the insertion of the medial rectus muscle, presumably due to incomplete local excision initially. a prominent, central, basophilic nucleolus ( F i g . 6 ) . Some cells had centrally placed nuclei or more than one nucleus. Many of the cells contained much glycogen, causing an apparent strand-like separation of the cyto plasm from the sarcolemma, suggesting large empty spaces with the formation of spider
DECEMBER, 1975
cells (Fig. 8 ) . Sedulous microscopic exam ination showed cells with well-organized cross striations (Fig. 9 ) . T h e r e were m;:ny cells with multiple, acidophilic, rod-like struc tures, so-called "myosin crystals" ( F i g . 10). Comment—We discovered this case of adult-type rhabdomyoma during our review of rhabdomyosarcomas on file here. The case was misdiagnosed as a rhabdomyosarcoma in 1938, before the diagnostic criteria for rhab domyosarcoma and rhabdomyoma had been clearly established. Jones, Reese, and Kraut 7 described this patient in a series of orbital rhabdomyosarcoma cases (Case 14) in 1966.
DISCUSSION
Rhabdomyomas most commonly occur in the hf*art« nt
