Harold J. Sobel

Fibrous mesotheliomas (pseudofibroma) of the scrotal sac: A light and ultrastructural study

Fibrous mesotheliomas of the scrotal sac are described. Similar tumors have been previously reported as fibromas and pseudofibromas and have been considered to be non‐neoplastic, reactive, fibrous lesions. Ultrastructural evidence for a mesothelial origin for these tumors is presented. The value of ultrastructural study in the classification of tumors arising in or on mesothelial lined surfaces is stressed.

An experimental model for treatment of mesothelioma

A peritoneal mesothelioma was induced by asbestos in a hamster, and was established in serial transfer to new hosts by injection of peritoneal effusion containing tumor cells. Biologically and histopathologically, this tumor is similar to its human counterpart. Three drugs were tested for efficacy using this model. Survival time was used as the only parameter of response and was compared with survival time of controls. Survival time increased 25 to 50% after short regimens of doxorubicin or 5‐fluorouracil. Survival time increased up to 308% after long‐continued treatments with cyclophosphamide. No cures were achieved.

Optically Clear Endometrial Nuclei

The ultrastructure of optically clear endometrial nuclei is presented. These nuclear alterations have been found in spontaneous abortion, term pregnancy, endometriosis, and uterine choriocarcinoma.

Histologic subtypes of small cell carcinoma of the lung: Response to therapy

Abstract Seventy-seven patients with extensive small cell carcinoma of the lung were initially treated with the same combination chemotherapy consisting of cyclophosphamide and doxorubicin. All cases were retrospectively subdivided according to their histological subtype as proposed by the World Health Organization Lung Cancer Classification (WHO): the classic lymphocyte-like (oat cell), type 21 , and intermediate cell, type 22 . Type 21 has an objective response rate of 43% and type 22 a response rate of 23% . Analysis of the data revealed that the median survival for WHO type 21 was 30.4 weeks; whereas median survival for type 22 was 17.2 weeks (P = 0.04 ). This difference in subtype response was also seen when response was corrected for Karnofsky initial performance status 40–70 but not for performance status 80–100 . Type 21 small cell carcinoma appears to offer a higher response rate to chemotherapy and a longer survival than type 22 .