Journal of Veterinary Diagnostic Investigation

Comparison of immunohistochemical profiles of ovarian germ cells in dysgerminomas of a captive maned wolf and domestic dogs

We characterized the immunohistochemical expression profiles of dysgerminomas from a 16-y-old maned wolf and 13 domestic dogs using the following biomarkers: Sal-like protein 4 (SALL4), octamer-binding transcription factor 3/4 (OCT3/4), placental alkaline phosphatase (PLAP), c-kit, and vimentin. The maned wolf had nonspecific and long-standing clinical signs of lethargy, anorexia, and weight loss, and was euthanized because of poor prognosis. At autopsy, the left ovary was effaced by a 12 × 8 × 6 cm mass, comprised of anaplastic cells with a mitotic count of 20 mitoses in 10 high power fields. Dysgerminomas from 7 of 13 domestic dogs had nuclear expression of SALL4. Dysgerminomas from the maned wolf and 2 domestic dogs had both nuclear and cytoplasmic expression of SALL4. Cytoplasmic expression of PLAP and OCT3/4 was present in dysgerminomas from the maned wolf and 3 (PLAP) or 4 (OCT3/4) domestic dogs. All dysgerminomas expressed vimentin. Membranous c-kit expression was rare in the dysgerminoma from the maned wolf, and variable in dysgerminomas from 4 domestic dogs. A dysgerminoma from a domestic dog had cytoplasmic expression of c-kit. SALL4 is a useful marker to confirm germ cell origin of dysgerminoma in canids.

Ovarian adenocarcinoma with metastases in a white rhinoceros

A 36-y-old white rhinoceros ( Ceratotherium simum) was presented with respiratory distress, sanguineous vaginal exudate, and anorexia. The clinical signs progressed over 40 d, and the rhinoceros died. Autopsy revealed significant ascites; a unilateral, 12.5-cm diameter, polypoid mass in the left ovary; a white, firm transmural mass in the right uterine horn; a white, friable mass in the lung; and white-to-tan, friable small nodules in the diaphragm. Histologic examination revealed similar neoplastic cells in the masses in all 4 locations, composed predominantly of epithelial cells proliferating in a tubulopapillary pattern with significant nuclear atypia and numerous atypical mitotic figures (18–42 per 2.37 mm2). Immunohistochemistry for CK7 (cytokeratin 7) and CK20 (cytokeratin 20) suggest that the ovarian, pulmonary, and diaphragmatic lesions were of ovarian origin and that the ovary was the primary tumor site.

Benign mixed Müllerian (duct) vaginal tumor in a 12-y-old goat

In human and veterinary medicine, mixed Müllerian tumors (MMTs) are rarely diagnosed neoplasms of the tubular female genital tract. Although there are case reports of malignant MMTs in various species, benign MMTs have only been described once in a macaque. Here we present a case of benign MMT in a 12-y-old goat, and review the literature on uterine, cervical, and vaginal neoplasia in goats. The doe was presented with vaginal discharge and was euthanized because of the high suspicion of intraabdominal neoplasia. On gross examination, an ulcerated vaginal mass was identified. Histologically, 2 distinct cell populations were present: smooth muscle cells that were well differentiated and positive for alpha–smooth muscle actin, and ciliated columnar epithelial cells that lined ductal structures and had no signs of malignancy. These findings led to the diagnosis of neoplasia of Müllerian origin. Benign MMT should be considered as a differential diagnosis for uterine and vaginal neoplasms in goats.

Comparison of anti-Müllerian hormone and inhibin immunolabeling in canine and equine granulosa cell tumors

Granulosa cell tumors (GCTs) are common ovarian neoplasms in the mare and bitch that can be challenging to diagnose on histopathology. Inhibin has long been the standard immunohistochemical (IHC) marker for GCTs; however, anti-Müllerian hormone (AMH) has not been evaluated widely as an IHC marker in the bitch and mare. We compared the efficacy of AMH and inhibin as IHC markers in canine and equine GCTs. We selected retrospectively 18 equine and 15 canine cases. All equine tumors were dominated by a cystic pattern; canine tumors often had solid patterns. Both inhibin and AMH had similar punctate cytoplasmic patterns of immunolabeling, although labeling intensity was variable; distribution and intensity of labeling were unrelated to the histomorphologic pattern. Labeling for AMH occurred in 12 of 15 canine and 18 of 18 equine cases. Labeling for inhibin occurred in 15 of 15 canine and 18 of 18 equine cases. AMH in equine GCTs often had stronger immunolabeling than inhibin, and granulosa cells were labeled more extensively. Inhibin and AMH performed comparably in bitches, but AMH had more diffuse immunolabeling than inhibin in mares.

Adenofibroma of the uterine tube in a pig

A 10-y-old, 145-kg, pet Large Black domestic pig with a history of heart failure, which was unresponsive to furosemide, and an enlarged abdomen was submitted for postmortem examination. An 11-kg, pale-pink, firm, multinodular mass was found in the region of the right ovary. On histologic examination, the mass appeared to originate from the wall of the uterine tube; there was no evidence of metastasis. Histologically, the mass was a biphasic tumor of epithelial and spindle cells. The epithelium was proliferative, not trapped residual glands, and was randomly dispersed through the spindle cell population as clusters and tubules lined by a monolayer of cuboidal cells. The spindle cell population resembled a fibroma with abundant collagen. There were no mitotic figures in either of the neoplastic cell populations. The uterus had cystic endometrial hyperplasia. Based on the histologic and immunohistochemical findings, this case fulfills the criteria of an adenofibroma.