Malignant mesenchymoma arising in an incisional scar of the abdominal wall

Diagnosis and treatment considerations in a case of malignant mesenchymoma in an African fur seal (Arctocephalus pusillus)

A 20-yr-old African fur seal (Arctocephalus pusillus) presented with a slowly growing mass located on the dorsum at the level of the last thoracic vertebrae. The mass was hard, 10 cm in diameter, and not adherent to the underlying tissues. Multiple biopsies were collected for histopathology and revealed extensive areas of necrosis, small nodules of malignant mesenchymal proliferation with areas of chondroid metaplasia, and atypical cells in vessel walls. The morphologic diagnosis was suggestive of malignant mesenchymal neoplasia originating from the vascular wall. The mass was removed 1 mo later due to ulceration and infection. Histologically, based on the World Health Organization's classification of neoplastic processes in domestic animals, the tumor was consistent with malignant mesenchymoma. The margins of resection revealed the presence of neoplastic cells. Based on these results, the particular species involved, the high local invasiveness, and the high metastatic index of this malignant tumor in domestic mammals and humans, the prognosis was poor. The animal died 6 mo later with metatastic disease.

An intra-abdominal malignant mesenchymoma associated with nonabsorbable sutures in a ferret (Mustela putorius furo)

A 6-year-old ferret (Mustela putorius furo) was presented with abdominal enlargement. Clinical examination revealed an intra-abdominal mass measuring approximately 5 cm in diameter. Abdominal survey radiographs revealed a sharply marginated mass with multifocal radiodense foci, suggestive of pathologic calcification. A complete blood cell count revealed a moderate, normocytic, normochromic, nonregenerative anemia. The mass was surgically removed en bloc, fixed in 10% neutral buffered formalin solution, and routinely processed for histologic and immunohistochemical investigation. The neoplastic tissue consisted of a mixed neoplastic cell population, including osteosarcoma and fibrosarcoma components. Immunohistochemistry revealed that both neoplastic cell populations were positive for vimentin and negative for actin (smooth and striated), desmin, and myoglobin. Nonabsorbable suture material was admixed with the neoplastic tissue in the histologic section. This material was birefringent when viewed microscopically under polarized light.

Cutaneous carcinosarcoma: adnexal vs. epidermal types define high- and low-risk tumors. Results of a meta-analysis

OBJECTIVE

We report four cases of cutaneous carcinosarcoma (CS) and perform a meta-analysis of the cutaneous CS literature.

RESULTS

CS occurred in elderly patients (mean of 80 years) on sun-damaged skin, and were keratotic papules of short duration. They did not recur after excision. CS exhibited basal cell carcinoma mixed with atypical fibroxanthoma cell populations. Immunophenotyping revealed vimentin+/keratin- spindle cells and vimentin-/keratin+ epithelial cells. Three cases exhibited p53 protein expression of both carcinomatous and sarcomatous components. Literature review identified 38 cases of cutaneous CS that could be broadly classified into two distinct groups. Epidermal-derived (basal or squamous cell carcinoma epithelial component) CS arose on the sun-damaged skin of the head and neck of elderly males (mean age 72 years) and had a 70% 5-year disease-free survival. In contrast, adnexal CS (spiradenocarcinoma, porocarcinoma, proliferating tricholemmal cystic carcinoma, or matrical carcinoma) occurred in younger patients (mean age 58 years), showed recent growth in a long-standing nodule and had a 25% 5-year disease-free survival. Age less than 65 years, recent growth, long-standing skin tumor, and tumor size greater than 2 cm significantly correlated with poor outcome.

CONCLUSIONS

Cutaneous CS is an aggressive skin cancer with high risk for advanced disease. Significant risk factors exist whose identification will allow for better management of CS patients.

Malignant mesenchymoma arising from a uterine leiomyoma in the menopause

BACKGROUND

Malignant mesenchymoma is a rare tumor and location in the uterus is even rarer. We describe the first case of malignant mesenchymoma arising from a uterine fibroid in the menopause.

CASE REPORT

A 64-year-old woman presented with abdominal pain and underwent surgery for a large "uterine fibroid" with suspicious features on ultrasound scan. The mass had developed after the menopause. Histology showed benign leiomyomatous tissue with malignant areas consistent with malignant mesenchymoma.

CONCLUSION

We report the first case of malignant mesenchymoma arising from the uterus in menopause. Certain radiological features may be associated with this tumor. Due to its rarity, information on management of uterine malignant mesenchymoma is lacking and management options of uterine leiomyosarcomas are reviewed as a surrogate.