Malignant deciduoid mesothelioma of the pleura: Report of two cases with long survival

Aims: To present two rare cases of malignant mesotheliomas with deciduoid features arising in the pleura, both with long survival. Methods and results: These two cases of deciduoid mesotheliomas were observed in adult patients (one 73-year-old male and one 23-year-old female). Only the male had a history of occupational asbestos exposure, whereas the woman had a history of familial mesothelioma. A deciduoid morphology was predominant and focal areas with tubular-papillary features were noted. The tumour cells were positive for cytokeratins, HMBE-1, calretinin, EMA and mitochondrion antibodies. The follow-up data did not suggest a particularly poor prognosis; the mean survival observed was 23 months (17 and 39 months, respectively). Conclusions: This deciduoid mesothelioma histological subtype does not appear to represent an unfavourable prognostic category.