PEDUNCULATED SCROTAL MASS: LEIOMYOMA OF SCROTUM ANURAG K. DAS, M.D. DAVID BOLICK, M.D. NANCY A. LITTLE, M.D. PHILIP J. WALTHER, M.D.,
PH.D.
From the Department of Surgery, Division of Urology, and the Department Pathology, Duke University School of Medicine, and the Urology Section, Durham VA Medical Center, Durham, North Carolina
of
ABSTRACT-Scrotal leiomyomas of the tunica dartos are extremely rare and usually misdiagnosed. A case ofa pedunculated mass observed expectantly over thirty years demonstrates the benign oncologic natural history of this lesion despite its capability for substantial growth. Only limited local surgical management of such lesions is indicated.
Leiomyomas of the scrotum are rare. First described by Forster in 1858, comprehensive reviews of cutaneous and subcutaneous leiomyomas have reported only 23 cases1m4;a careful review of the world literature has identified an additional 7 cases.5m10Although 2 of the first several cases reported were pedunculated masses,’ this presentation is not widely appreciated since most scrotal wall leiomyomas are solitary, asymptomatic lesions less than 3 cm in diameter. Because of their extreme rarity they are nearly always misdiagnosed preoperatively and often confused with a fibroma or an epiderma1 inclusion cyst. 3 We present one of the largest documented scrotal leiomyomas whose slow growth had been observed by the patient for over thirty years. It documents the natural history of this unusual lesion; its slow growth, lack of invasive character, and characteristic cutaneous location of origin would appear to predispose to a benign clinical course. Recognition of such a case strongly suggesting the diagnosis of this benign lesion dictates a conservative surgical
FICLJHE 1.
pedunculated
376
Large right scrotal leiomyoma;
mass is
and without skin ulceration.
UROLOGY /
APRIL
1992 i
VOI,UfvlE XXXIX. NUllHER
4
FIGURE2. Cut section of specimen revealing nodular tumor with whorled appearance. management of this lesion since its transformation to a malignant variant (leiomyosarcoma) probably does not occur. Clinical Report A fifty-six-year-old black man with end-stage renal disease was admitted for creation of an arteriovenous fistula for dialysis. On routine examination he was found to have a large right scrotal mass. The patient had first noticed the mass wh’en it was pea-sized, about thirty years ago, and it had been slowly enlarging ever since. Physical examination revealed a firm, nontender, pedunculated mass without skin ulceration measuring 5 x 4 x 4 cm (Fig. 1). The mass was distinctly separate from the testicle, epididymis, and spermatic cord which were all normal. No hernias were present nor were inguinal lymph nodes palpable. Under local anesthesia, the mass was excised with wide margins and the scrotum was primarily closed; the postoperative course was uneventful. Pathology Cross ‘examination revealed a 5 x 4 x 4 cm firm, tan-yellow mass located in the deep derma1 tissue and bulging from the cut surface of the specimen (Fig. 2). The overlying scrotal skin, papillary dermis, and upper reticular dermis were uninvolved. Microscopic examination revealed a round, nonencapsulated tumor of
FIGURE3. Scrotal skin with large leiomyoma underlying normal smooth muscle of tunica dartos (arrows) (X 11.5). the smooth muscle, lying within the deep reticular dermis of the scrotum, below the network of smooth muscle of the dartos (Fig. 3). The tumor was composed of interlacing bundles of smooth muscle which focally extended into the surrounding dermis. The spindled cells of these bundles each contained a single, centrally located, oval-shaped nucleus (Fig. 4). The cytoplasm had a longitudinal fibrillary appearance, which showed distinct myofibrils with Masson stain. There were no mitoses, no nuclear or cytologic atypia, no cross striations, and no giant cells. The smooth muscle bundles surrounded and often became continuous with many of the numerous small and medium-sized bl.ood vessels within the tumor. Sclerosis was: present throughout the tumor, most prominently in the central areas. The smooth muscle bundles stained positively for actin and desmin by immunoperoxidase preparations and stained red with the Masson stain. The overlying epidermis, papillary dermis, and upper reticular dermis were unremarkable.
Scrotal FIGURE 4. bundles of spindled (x 130).
Eeiomyoma showing interlacing cells with oval-shaped nucleoli
Comment Although the differential diagnosis of scrotal lesions distinctly separate from the testis and adnexal structures includes squamous cell carcinoma, basal cell carcinoma, Paget disease, fibroma, lipoma, myxoma, hemangioma, lymphangioma, liposarcoma, rhabdomyosarcoma, leiomyosarcoma, leiomyoma, and epidermal inclusion cyst, the last is clearly the most common lesion; as a result, other lesions of a rubbery character are dismissed as epidermal cysts. However, the presence of a pedunculated character should strongly suggest a leiomyoma. Challand and Forster’s’ early experience with pedunculated scrotal leiomyomas coincides with the clinical course in our patient who never sought medical attention for this lesion. However, the characteristic description in the literature is that of a painless, noninflamed, small cutaneous lesion from pea to walnut size usually present for several years prior to resection; it is not surprising that most are misdiagnosed.2 Although such lesions can occur at
378
any time from infancy to senility, it is characteristically a lesion that is surgically treated in late middle age or later. Leiomyomas of the skin and subcutaneous tissue are divided into angioleiomyomas, piloleiomyomas, and genital areolar leiomyomas. Arising from the vascular smooth muscle, angioleiomyomas are usually subcutaneous, while piloleiomyomas, arising from the pilar arrector muscles within the dermis, are cutaneous and often multifocal. Genital-areolar leiomyomas arise within the smooth muscle of the deep reticular dermis of genital skin and nipple, that is, the smooth muscle of the scrotal dartos (the so-called muscularis sexualis) or labia majora in females, as well as around the mammary areolae (muscularis mammillae). Whereas both piloleiomyomas and angioleiomyomas are relatively common, genital-areolar leiomyomas are seen far less frequently. Vulvar leiomyomas may be more common than either scrotal or areolar sites.‘,3,4 Siegal and Gaffey2 found only 10 scrotal leiomyomas in 127 patients with primary neoplasms of the scrotal wall, while Yokoyama et ~1.~ found only 4 scrotal leiomyomas in more than 19,000 cases of benign soft tissue tumors. This case represents only the second such scrotal lesion seen in a black male, the only other case reported by Fisher and Helwig.3 The 10 cases reported by Seigal and Gaffey from the Mayo Clinic were all in white patients, but this may represent the ethnic demographics of that institution’s location. However, Stout’s’ treatise on superficial leiomyomas also suggested that cutaneous leiomyomas are extremely rare in blacks. Of the first 88 cases of cutaneous leiomyomas (all sites), only 1 patient was black. Whether cultural or socioeconomic factors impact on this apparent racial distribution skew is not clear; certainly an asymptomatic lesion often does not elicit intervention if medical care is not easily available. The presence of a pedunculated scrotal mass should strongly suggest the diagnosis of leiomyoma since 7 of the 31 documented leiomyomas have been pedunculated.1~2~4~5~s Although these lesions are predominantly painless, this case demonstrates that the natural history of such lesions is to slowly grow in size until they can become cosmetically troublesome. This case and the literature suggest that malignant degeneration of leiomyomas into leiomyosarcomas is probably rare; this lesion was present in this patient for thirty years but showed no evidence of malignancy. Siegel and Gaffey2 have reported 1
UROLOGY
/ APRIL
1992 /
VOLUME
XXXIX. NUMBER 4
References
case which was “recurrent” but it is possible that this was a multifocal tumor. At least one report documents the erosion of one such large scrotal leiomyoma, and there is one documented case of bilaterality.“-” Nevertheless, surgery for even large lesions should be conservative if it is clear that it does not arise from the testis or adnexal structures but is of cutaneous origin; pathologic frozen section should be utilized to confirm the clinical suspicion if there is doubt regarding the extent of surgical excision. If frozen section suggests the diagnosis of leiomyoma, wide local excision clearly suffices for management of such lesions.
1. Stout AP: Solitary cutaneous
and subcntanrons Iciomyoma, Am J Cancer 29: 435 (1937). 2. Seigel Ce and Gaffer TA: Solitary leiomyomas Tarising tram the tunica dartos scroti, J Ural 116: 69 (1976). 3. Fisher MC, and Helwig EB: Leiomyomas of thcp skin, Arch Dermatol 88: 510 (1963).
5. Iloreta AT, Berikov H, and Newman HR: Lciomyoma of the scrotum, Urology 10: 48 (1977). 6. Tomera KM, Gaffey TA, Goldstein IS, and Zincke II: Leiomyoma of scrotum, Urolog); 18: 388 (1981). 7. Livne PM, pt al: Leiomyoma of the scrotum Arch Dermatol 119: 358 (1983). 8. Grace DA: L&myoma of the scrotum: a case report and review of the literature. J Urol 191: 396 (1964). 9. Herbert PA: lirologic Pathology, Philadelphia. lxa & Fehiger, 1952. 10. Benson CD, Webster JD, and McDonald JR: Leiomyoma of the tunica dartos scroti-a case report, J Mich Mrd Sot 60: 1553 (1961).
Duke Universit), Medical Center, Box 3314 Durham, North Carolina 2’7710 (DR. WALTHER)
I’ROLO
PH.D.
From the Department of Surgery, Division of Urology, and the Department Pathology, Duke University School of Medicine, and the Urology Section, Durham VA Medical Center, Durham, North Carolina
of
ABSTRACT-Scrotal leiomyomas of the tunica dartos are extremely rare and usually misdiagnosed. A case ofa pedunculated mass observed expectantly over thirty years demonstrates the benign oncologic natural history of this lesion despite its capability for substantial growth. Only limited local surgical management of such lesions is indicated.
Leiomyomas of the scrotum are rare. First described by Forster in 1858, comprehensive reviews of cutaneous and subcutaneous leiomyomas have reported only 23 cases1m4;a careful review of the world literature has identified an additional 7 cases.5m10Although 2 of the first several cases reported were pedunculated masses,’ this presentation is not widely appreciated since most scrotal wall leiomyomas are solitary, asymptomatic lesions less than 3 cm in diameter. Because of their extreme rarity they are nearly always misdiagnosed preoperatively and often confused with a fibroma or an epiderma1 inclusion cyst. 3 We present one of the largest documented scrotal leiomyomas whose slow growth had been observed by the patient for over thirty years. It documents the natural history of this unusual lesion; its slow growth, lack of invasive character, and characteristic cutaneous location of origin would appear to predispose to a benign clinical course. Recognition of such a case strongly suggesting the diagnosis of this benign lesion dictates a conservative surgical
FICLJHE 1.
pedunculated
376
Large right scrotal leiomyoma;
mass is
and without skin ulceration.
UROLOGY /
APRIL
1992 i
VOI,UfvlE XXXIX. NUllHER
4
FIGURE2. Cut section of specimen revealing nodular tumor with whorled appearance. management of this lesion since its transformation to a malignant variant (leiomyosarcoma) probably does not occur. Clinical Report A fifty-six-year-old black man with end-stage renal disease was admitted for creation of an arteriovenous fistula for dialysis. On routine examination he was found to have a large right scrotal mass. The patient had first noticed the mass wh’en it was pea-sized, about thirty years ago, and it had been slowly enlarging ever since. Physical examination revealed a firm, nontender, pedunculated mass without skin ulceration measuring 5 x 4 x 4 cm (Fig. 1). The mass was distinctly separate from the testicle, epididymis, and spermatic cord which were all normal. No hernias were present nor were inguinal lymph nodes palpable. Under local anesthesia, the mass was excised with wide margins and the scrotum was primarily closed; the postoperative course was uneventful. Pathology Cross ‘examination revealed a 5 x 4 x 4 cm firm, tan-yellow mass located in the deep derma1 tissue and bulging from the cut surface of the specimen (Fig. 2). The overlying scrotal skin, papillary dermis, and upper reticular dermis were uninvolved. Microscopic examination revealed a round, nonencapsulated tumor of
FIGURE3. Scrotal skin with large leiomyoma underlying normal smooth muscle of tunica dartos (arrows) (X 11.5). the smooth muscle, lying within the deep reticular dermis of the scrotum, below the network of smooth muscle of the dartos (Fig. 3). The tumor was composed of interlacing bundles of smooth muscle which focally extended into the surrounding dermis. The spindled cells of these bundles each contained a single, centrally located, oval-shaped nucleus (Fig. 4). The cytoplasm had a longitudinal fibrillary appearance, which showed distinct myofibrils with Masson stain. There were no mitoses, no nuclear or cytologic atypia, no cross striations, and no giant cells. The smooth muscle bundles surrounded and often became continuous with many of the numerous small and medium-sized bl.ood vessels within the tumor. Sclerosis was: present throughout the tumor, most prominently in the central areas. The smooth muscle bundles stained positively for actin and desmin by immunoperoxidase preparations and stained red with the Masson stain. The overlying epidermis, papillary dermis, and upper reticular dermis were unremarkable.
Scrotal FIGURE 4. bundles of spindled (x 130).
Eeiomyoma showing interlacing cells with oval-shaped nucleoli
Comment Although the differential diagnosis of scrotal lesions distinctly separate from the testis and adnexal structures includes squamous cell carcinoma, basal cell carcinoma, Paget disease, fibroma, lipoma, myxoma, hemangioma, lymphangioma, liposarcoma, rhabdomyosarcoma, leiomyosarcoma, leiomyoma, and epidermal inclusion cyst, the last is clearly the most common lesion; as a result, other lesions of a rubbery character are dismissed as epidermal cysts. However, the presence of a pedunculated character should strongly suggest a leiomyoma. Challand and Forster’s’ early experience with pedunculated scrotal leiomyomas coincides with the clinical course in our patient who never sought medical attention for this lesion. However, the characteristic description in the literature is that of a painless, noninflamed, small cutaneous lesion from pea to walnut size usually present for several years prior to resection; it is not surprising that most are misdiagnosed.2 Although such lesions can occur at
378
any time from infancy to senility, it is characteristically a lesion that is surgically treated in late middle age or later. Leiomyomas of the skin and subcutaneous tissue are divided into angioleiomyomas, piloleiomyomas, and genital areolar leiomyomas. Arising from the vascular smooth muscle, angioleiomyomas are usually subcutaneous, while piloleiomyomas, arising from the pilar arrector muscles within the dermis, are cutaneous and often multifocal. Genital-areolar leiomyomas arise within the smooth muscle of the deep reticular dermis of genital skin and nipple, that is, the smooth muscle of the scrotal dartos (the so-called muscularis sexualis) or labia majora in females, as well as around the mammary areolae (muscularis mammillae). Whereas both piloleiomyomas and angioleiomyomas are relatively common, genital-areolar leiomyomas are seen far less frequently. Vulvar leiomyomas may be more common than either scrotal or areolar sites.‘,3,4 Siegal and Gaffey2 found only 10 scrotal leiomyomas in 127 patients with primary neoplasms of the scrotal wall, while Yokoyama et ~1.~ found only 4 scrotal leiomyomas in more than 19,000 cases of benign soft tissue tumors. This case represents only the second such scrotal lesion seen in a black male, the only other case reported by Fisher and Helwig.3 The 10 cases reported by Seigal and Gaffey from the Mayo Clinic were all in white patients, but this may represent the ethnic demographics of that institution’s location. However, Stout’s’ treatise on superficial leiomyomas also suggested that cutaneous leiomyomas are extremely rare in blacks. Of the first 88 cases of cutaneous leiomyomas (all sites), only 1 patient was black. Whether cultural or socioeconomic factors impact on this apparent racial distribution skew is not clear; certainly an asymptomatic lesion often does not elicit intervention if medical care is not easily available. The presence of a pedunculated scrotal mass should strongly suggest the diagnosis of leiomyoma since 7 of the 31 documented leiomyomas have been pedunculated.1~2~4~5~s Although these lesions are predominantly painless, this case demonstrates that the natural history of such lesions is to slowly grow in size until they can become cosmetically troublesome. This case and the literature suggest that malignant degeneration of leiomyomas into leiomyosarcomas is probably rare; this lesion was present in this patient for thirty years but showed no evidence of malignancy. Siegel and Gaffey2 have reported 1
UROLOGY
/ APRIL
1992 /
VOLUME
XXXIX. NUMBER 4
References
case which was “recurrent” but it is possible that this was a multifocal tumor. At least one report documents the erosion of one such large scrotal leiomyoma, and there is one documented case of bilaterality.“-” Nevertheless, surgery for even large lesions should be conservative if it is clear that it does not arise from the testis or adnexal structures but is of cutaneous origin; pathologic frozen section should be utilized to confirm the clinical suspicion if there is doubt regarding the extent of surgical excision. If frozen section suggests the diagnosis of leiomyoma, wide local excision clearly suffices for management of such lesions.
1. Stout AP: Solitary cutaneous
and subcntanrons Iciomyoma, Am J Cancer 29: 435 (1937). 2. Seigel Ce and Gaffer TA: Solitary leiomyomas Tarising tram the tunica dartos scroti, J Ural 116: 69 (1976). 3. Fisher MC, and Helwig EB: Leiomyomas of thcp skin, Arch Dermatol 88: 510 (1963).
5. Iloreta AT, Berikov H, and Newman HR: Lciomyoma of the scrotum, Urology 10: 48 (1977). 6. Tomera KM, Gaffey TA, Goldstein IS, and Zincke II: Leiomyoma of scrotum, Urolog); 18: 388 (1981). 7. Livne PM, pt al: Leiomyoma of the scrotum Arch Dermatol 119: 358 (1983). 8. Grace DA: L&myoma of the scrotum: a case report and review of the literature. J Urol 191: 396 (1964). 9. Herbert PA: lirologic Pathology, Philadelphia. lxa & Fehiger, 1952. 10. Benson CD, Webster JD, and McDonald JR: Leiomyoma of the tunica dartos scroti-a case report, J Mich Mrd Sot 60: 1553 (1961).
Duke Universit), Medical Center, Box 3314 Durham, North Carolina 2’7710 (DR. WALTHER)
I’ROLO
