Epithelioid Cells ; pathology ; Humans ; Soft Tissue Neoplasms ; pathology

OBJECTIVETo further elucidate the clinical and pathologic features of retiform hemangioendothelioma (RH) and its clinical spectrum.

METHODSEight cases of RH were reviewed. The clinicopathologic profiles, immunophenotypes and outcome data were investigated.

RESULTSAll 8 cases occurred in females with a mean age at presentation of 40 years (range, 13-69 years). Five tumors arose in the skin of the head and neck region and lower extremities, two in the long bones and one in the spleen. Clinically, the patients presented with a slowly growing cutaneous plaque or subcutaneous nodule, pain of the upper arm, and dull pain and discomfort in the left hypochondrium respectively. Grossly, the tumor appeared as a non-encapsulated gray-yellowish to tan-brown mass with a mean diameter of 2.6 cm (range, 0.8-5.0 cm). On histology, it was composed of delicate branches of elongated vessels lined by a layer of hobnail or matchstick endothelium, exhibiting a retiform pattern with close resemblance of the normal rete testis. Cords or solid nests of epithelioid cells were noted adjacent to the well-formed vessels. In three cases, dilated vascular spaces with formation of intravascular papillary tufts were observed, features overlapping with Dabska tumor. There was usually marked lymphocytic infiltration in the stroma which was also hyalinized in some cases. One case had regional lymph node metastasis. By immunohistochemistry, all cases consistently expressed endothelial markers, including CD31 (8/8), human coagulation factor VIII (5/8), CD34 (5/7) and D2-40 (1/2). Two of six cases with follow-up information (18-67 months) developed local recurrences, but distant metastasis was not identified.

CONCLUSIONSRH is a distinctive vascular tumor of adulthood characterized by retiform growth of vessels with striking hobnail endothelium. Although the tumor occurs predominantly in the skin, the long bones and the spleen can be occasionally affected. The presence of Dabska tumor-like areas in RH may suggest a morphologic continuum between these two entities, comprising the family of hobnail hemangioendothelioma. Familiarity with the characteristic features of this vascular tumor of intermediate malignancy will help in the differential diagnosis of vascular neoplasms with hobnail endothelium.

Adolescent ; Adult ; Aged ; Biomarkers, Tumor ; Bone Neoplasms ; pathology ; Diagnosis, Differential ; Epithelioid Cells ; pathology ; Female ; Hemangioendothelioma ; pathology ; Humans ; Immunohistochemistry ; Immunophenotyping ; Middle Aged ; Neoplasm Recurrence, Local ; Skin Neoplasms ; pathology ; Splenic Neoplasms ; pathology ; Young Adult

OBJECTIVETo elaborate on the clinical and pathologic features of sarcomatoid malignant mesothelioma (SMM), its diagnostic criteria and differential diagnoses.

METHODSTwenty-two cases of SMM retrieved from in-house and consultation files (between January 2009 to September 2013) were reviewed with emphasis on the clinicopathologic characteristics, immunophenotypes and the prognostic impact.

RESULTSThe mean age of the patients was 54 years (ranged from 24-73 years). There was no sexual predilection and the majority of the patients did not have history of asbestos exposure. Overall, 14 tumors developed in the pleura and 8 cases arose from the peritoneal cavity. Clinically, patients presented signs and symptoms in accord with the location of the tumors, notably coughing, shortness of breath, and chest pain for patients with pleural origin, and nausea, abdominal distention and abdominal pain for those with peritoneal primary. In most cases, CT and MRI scan demonstrated lobulated masses (8/11). However, diffuse infiltrative growth patterns were observed exclusively in a minority of pleural cases (3/11). No visceral lesion was observed in any case. Histologically, 19 cases had either fibrosarcomatous or undifferentiated pleomorphic sarcoma-like appearance. Two cases were consistent with desmoplastic mesothelioma. One case contained osteosarcomatous element. All cases expressed pan-cytokeratin (AE1/AE3), and most cases were also positive for D2-40 (15/20). The staining of calretinin (9/21) and WT1 (10/14) was generally weak and focal. They were all negative for TTF-1, napsin A, SP-A, p63 and CD34. Follow-up information (range from 1 to 36 months) was available in 11 cases, 6 of which were alive with unresectable tumor, 1 patient with recurrent disease and 4 patients succumbed to disease. The overall survival was 5 months (mean 8 months).

CONCLUSIONSThe diagnosis of SMM is achieved by comprehensive evaluation of medical history, imageological and pathological findings. Since calretinin immunoreactivity is infrequently observed in SMM, application of pan-cytokeratin and D2-40 immunostains offers a reasonable alternative for diagnosis. Diagnosis of SMM can be made by excluding a variety of spindle cell neoplasms with overlapping features, such as sarcomatoid carcinoma, synovial sarcoma, solitary fibrous tumor and fibrous pleuritis.

Adult ; Aged ; Biomarkers, Tumor ; metabolism ; Carcinoma ; diagnosis ; pathology ; Diagnosis, Differential ; Humans ; Lung Neoplasms ; diagnosis ; pathology ; Mesothelioma ; diagnosis ; pathology ; Middle Aged ; Prognosis ; Sarcoma ; diagnosis ; pathology ; Solitary Fibrous Tumors ; diagnosis ; pathology