Dorthe Francis

Primary Hemangiopericytoma of the Lung

Hemangiopericytoma is a rare tumor, arising from pericytes. Its outcome is difficult to foretell, as the usual criteria for malignancy are unreliable in this neoplasm. Three cases of primary pulmonary hemangioperi-cytoma are presented and the pathologic and clinical aspects are briefly reviewed. All three patients were surgically treated, and two are still alive after 7 and 18 years without sign of recurrence or metastasis. The third patient, although still alive, has had three recurrences within 22 months and vertebral metastasis.

Peritoneal mesotheliomas in Danish women: Review of histopathologic slides and history of abdominal surgery

An unexpectedly large number of peritoneal mesotheliomas among women was reported to the Danish Cancer Registry during the years 1960 through 1985. In a case‐control study, we tested whether this was due to diagnostic misclassification or to direct exposure of the peritoneal membranes to talc during abdominal surgery. Tissue specimens were available from 96 reported peritoneal mesotheliomas; 35 cases (37%) were regarded as verified mesotheliomas, and 33 (34%) as possible mesotheliomas. Information on any intraabdominal surgery was obtained from the hospital records of these 68 cases and for 206 controls with a cancer of the uterined corpus or pancreas. No association was seen between peritoneal mesotheliomas and abdominal surgery performed more than 25 years prior to cancer diagnosis (odds ratio, 0.83; 95″ confidence interval, 0.35‐1.94).

Thvmomas and thvmic carcinomas

The morphological heterogeneity of thymomas has caused much confusion respecting their classification. Recently Kirchner & Müuller‐Hermelink (4) proposed a histological subclassification which has been claimed to represent an independent prognostic factor: medullary and mixed thymomas are benign; organoid and cortical type as well as well‐differentiated thymic carcinomas are low‐grade malignant tumors, which have the capacity to recur and spread, even if they are clinically benign. High‐grade malignant thymomas are always malignant. We present the clinicopathological data on 10 clinically benign and 14 clinically malignant thymomas. Having reclassified the thymomas, we found four low‐grade malignant examples among the clinically benign thymomas. It is important to identify this group of patients as they are at risk of tumor recurrence. However, further investigation is needed to support the validity of this subclassification system.

Spontaneous regression of a pleural thickening with the histological appearance of an inflammatory pseudotumour

The inflammatory nature of a tumour-like lesion not formerly observed in the parietal pleura was confirmed histologically using immunohistochemical analysis and clinically by spontaneous regression. A study of the literature revealed that the histological picture of the lesion was consistent with that of the rarely described inflammatory pseudotumour.