Microcystic variant of localized malignant mesothelioma accompanying an adenomatoid tumor‐like lesion

Abstract

The case of a 70-year-old man with a hitherto undescribed pleural mesothelioma is reported. The tumor was localized in the left lung apex and had invaded the parietal pleura. Histologically, the tumor was characterized by a proliferation of epithelioid cells and the formation of microcysts. The tumor cells were positive for calretinin and vimentin, and possessed abundant microvilli, indicating a mesothelial cell origin for the tumor. A high Ki-67 index and mitotic index, and the recurrence of the tumor after surgery, indicated malignancy. Based on the evidence, we propose that the tumor is a microcystic variant of a localized malignant mesothelioma.

Microcystic variant malignant mesothelioma presenting as a localized paraspinal mass

“…An FNA sample can be acceptable as an adequate specimen for definitive diagnosis of MM when immunohistochemistry studies can demonstrate mesothelial origin and exclude other differential diagnoses. The histomorphologic characteristic of the microcystic variant of pleural MM is well-described in a recent case report[5] but, to the best of our knowledge, this is the first case on which FNA was performed as the first-line investigation for primary diagnosis of a microcystic variant of localized MM.…”

Localised pleural malignant mesothelioma. Report of two cases simulating pulmonary carcinoma and review of the literature

“…However, our 2 cases presented as tumours with a predominantly intrapulmonary growth. This type of growth was partly present in only 2 of the previously reported cases [3,13]. It is noteworthy that, in all cases with intrapulmonary growth, a pre-operative diagnosis of lung carcinoma (primary or metastatic) was reached, without taking into consideration the use of immunohistochemistry to exclude a mesothelial origin (Table 2).…”

“…The rarity of localised malignant mesothelioma of the pleura is emphasised by the fact that only 12 cases have been fully documented to date in the English literature, with histology and immunohistochemistry consistent with mesothelioma (Table 2) [3,6,8,9,10,13].…”

Benign pulmonary epithelial inclusions within the pleura: a case report

“…Among malignant neoplasms, mesothelioma, bronchogenic carcinoma, and metastatic non-pulmonary carcinoma top the list [3-7]. Benign tumors also affect the pleura, including adenomatoid tumor and benign cystic mesothelioma [8-13].…”