Primary pseudomyogenic hemangioendothelioma of bone: case report and review of the literature.

Pseudomyogenic hemangioendothelioma (PMH) represents a multicentric recently characterized tumor type, generally presenting in young adults, of postulated vascular origin and intermediate malignancy. This entity tends to arise in the deep-seated dermal-subcutaneous locations, preferentially limited to one anatomic site, and may extend secondary to bone. PMH restricted to the skeletal system is rare. To our knowledge, only 19 cases with description of both histologic and clinical findings have been reported to date. We report the clinicopathological features of a further intraosseous PMH occurring in a 46-year-old woman involving the right patella. Histologic examination showed an infiltrating growth composed of sheets and fascicles of spindled to epithelioid large cells, with ample eosinophilic cytoplasm, large vesicular nuclei and prominent nucleoli, sometimes resembling rhabdomyoblastic tumor cells, without morphologic signs of vascular differentiation. At immunohistochemical examination, neoplastic cells stained diffusely for AE1/AE3 keratins, vimentin, ERG, FLI-1, INI-1, FOSB with only focal CD31 expression.The morphologic clues leading to the correct diagnosis of intraosseous PMH have been correlated with the data of the literature, and a special emphasis has been given to the differential diagnosis with other neoplasms, particularly epithelioid sarcoma, in order to avoid unnecessary radical surgery and to optimise possible treatment protocols.

Unclassified sex cord/gonadal stromal testis tumor with a "pure" spindle cell component: a case report.

Unclassified sex cord/gonadal stromal tumors (SCSTs) composed predominantly of spindle cells are rare. Very few cases have been documented to date. Here, we report a case of "pure" spindle cell tumor of the left testis in a 83-year old man whose morphological and immunohistochemical findings were consistent with a diagnosis of unclassified SCST and review the literature. Owing to the spindle cell pattern, the differential diagnosis with other benign and malignant spindle cell lesions is discussed.

Tall cell variant of papillary breast carcinoma: an additional case with review of the literature.

Papillary lesions of the breast can be one of the most challenging aspects of mammary pathology because of a wide morphologic spectrum that may be encountered in these lesions. An unusual breast tumor has been first classified as "breast tumor resembling the tall cell variant of papillary thyroid carcinoma" and subsequently renamed "tall cell variant of papillary breast carcinoma". To our knowledge, only 13 cases of this neoplasm have been reported so far. Metastasis to the breast is not an uncommon event and about 5% of all such cases are of the thyroid origin. We report the clinico-pathological and immunohistochemical features, together with a molecular screening for BRAF mutations, of an additional case of tall cell variant of papillary breast carcinoma occurring in a 65-year-old woman. The immunohistochemical and molecular clues leading to the correct diagnosis have been correlated with the data of the literature. Tall cell variant of papillary breast carcinoma represents a unique histologic subtype of mammary carcinoma of probably low malignant potential which has to be recognized to avoid misdiagnosis as metastatic carcinoma from the thyroid.

Primary synovial sarcoma of the kidney. A case report with pathologic appraisal investigation and literature review.

Synovial sarcoma (SS) is a soft tissue neoplasm with clearly defined histologic, immunohistochemical and molecular features that usually arises in the extremities of young adults. The occurrence of these tumors in the kidney is extremely rare and have been prevalently described in case reports. The objectives of this work were to evaluate the frequency of primary renal synovial sarcomas and the pathologic progression in recognition of this possibly under-diagnosed entity. A comprehensive review of the literature has also been performed with a focus on survival. We report the clinico-pathological features of an intrarenal SS occurring in a 67-year-old man. The tumour, measuring 4 cm in its greatest diameter, completely replaced the cortex and the medulla of the inferior region of the left kidney compressing the iliopsoas muscle. Radiological imaging was consistent with a renal cell carcinoma. Histologically, the tumour was composed of atypical monotonous vimentin+, CD99+, bcl-2+ spindle cells exhibiting a haphazard fascicular growth pattern and a high mitotic rate (3 to 5 mitoses per HPF). The diagnosis was supported by reverse transcription-polymerase chain reaction which demonstrated SYT-SSX2 gene fusion. The patient was alive with local recurrence of disease 24 months after surgery. Synovial sarcomas occurring in the kidney, in analogy to other sites, tend to have an aggressive biologic behaviour. Despite being extremely uncommon, with only 44 cases reported to date, they should be included in the differential diagnosis of benign and malignant spindle cell tumours of the kidney. This study also emphasizes the importance of a correct pathologic diagnosis for prognostic and therapeutic implications.

[Cutaneous angiolipoleiomyoma: a case report and literature review]. / Angiolipoleiomioma cutaneo: segnalazione di un caso e revisione della letteratura.

The Authors describe a rare case of cutaneous angiolipoleiomyoma in an acral location together with a brief literature review. A 62-year-old male presented with a slow-growing asymptomatic nodule, 2.2 cm in diameter, located in the subcutaneous tissue of the left calf. Ten months after surgical excision, the patient is alive and free of disease. Histologically, the lesion was well-circumscribed and contained three components: areas of mature fat tissue were intermingled with cellular areas of spindle eosinophilic cells, reminiscent of smooth muscle cells, and a complex mixture of vessels of different types and sizes. Immunohistochemically, the cellular spindle component was positive for vimentin and smooth muscle actin, and negative for S-100, HMB-45, MART-1 and oestrogen and progesterone receptors. The Authors discuss differential diagnosis with other benign lesions such as angioleiomyoma and subcutaneous angiomyolipoma.