Intermediately differentiated Sertoli-Leydig cell tumor (SLCT) with mucinous adenocarcinoma as heterologous element.
The National Cancer Institute estimated that 1.3 percent of women will be diagnosed with ovarian cancer at some point in their lifetime, with the number of new cases being 12.1 per 100,000 women per year in the USA (1). With respect to the classification and frequency of ovarian tumors, surface epithelial-stromal tumors are the most common, accounting for 60% of all ovarian tumors, followed by germ cell tumors (roughly 25%) (2). Sex cord-stromal tumors are the least common, accounting for roughly 8% of all ovarian tumors (2). Originally termed arrhenoblastomas by Meyer, SLCT are classified as sex cord-stromal tumors- already making SLCT a relatively rare tumor by virtue of the relative uncommonness of the sex cord-stromal group of tumors. Unsurprisingly, in the context of ovarian tumors, SLCT represent less than 0.5% of all cases (3). SCLT are divided into well-differentiated, intermediate differentiation, poorly differentiated, retiform, and mixed (2).
From an epidemiological perspective, SLCT is not a tumor of the elderly. The seminal paper by Young et all in 1985 is the largest series to date that evaluated the clinico-pathological features of 207 cases of SLCT in women, ranging from age 2 to 75 years old (3). Of the 207 patients evaluated, 75% of the cases occurred in women 30 years old or younger, and less than 10% of the cases occurred in women over 50 years of age. Some common presenting features included abdominal swelling, abdominal pain, post- menopausal bleeding, amenorrhea and virilization. Grossly, these tumors ranged from solid, to solid-cystic, to purely cystic. Microscopically, the majority of the cases were of intermediate differentiation (111 cases).
Morphologically, these tumors exhibit remarkable variation(4) and the presence of heterologous elements in these tumors is not uncommon. Previously reported heterologous elements in SLCT include mesenchymal derivatives such as skeletal muscle and cartilage (5), as well as endodermal derivatives (4). It should therefore come as no surprise that the heterologous elements exhibited in some SLCT may also be malignant. Some previously reported malignant heterologous elements in SLCT include rhabdomyosarcoma(6) and three previous cases of mucinous adenocarcinoma (4,7). With respect to mucinous carcinoma as a heterologous element of SLCT, the histological features may range from microscopic foci of mucinous adenocarcinoma (4) to extensive mucinous adenocarcinoma (7). The first two reported cases of heterologous elements of mucinous carcinoma by Young et al (1982) (4) described only microscopic foci of mucinous adenocarcinoma. A more recent case report (7) describes extensive heterologous elements of mucinous adenocarcinoma. This case, reported by Renu and Di, was reported in a 21 year old female presenting with lower abdominal pain and history of satiety and significant weight loss over a one month period.
Owing to the substantially low incidence of SLCT with mucinous adenocarcinoma as a heterologous element, information about the clinicopathological behavior of this group of tumors is limited. This limitation poses a particular problem with respect to two important tenants of oncology: (i) establishing an optimal management strategy and (ii) risk stratification and determination of prognosis. Current data suggests that gold standard treatment of SLCT is surgery (8), with adjuvant therapy being indicated in poorly differentiated SLCT or SLCT with heterologous elements (9). As of the time of writing this case report, there is no clear-cut data establishing the prognosis of SLCT with mucinous adenocarcinoma as the heterologous component and the significance of the element of mucinous adenocarcinoma is unclear with respect to metastatic potential.
Contributed by Dayne Ashman, MD and Esther Elishaev, MD