Prognostic significance of morphological growth patterns and mitotic index of epithelioid malignant peritoneal mesothelioma

Abstract

Our study highlights the prognostic importance of the solid growth pattern among diffuse epithelioid peritoneal mesotheliomas, and reaffirms mitotic index as a predictor of overall survival.

Peritoneal Mesothelioma with Residential Asbestos Exposure. Report of a Case with Long Survival (Seventeen Years) Analyzed by Cgh-Array

“…Because multimodal treatment is associated with a significant perioperative risk it is necessary to consider prognostic markers during patient selection. At present, the morphological growth patterns of the tumor and the mitotic index are the prevalent aspects used to select patient groups to be submitted to treatment options [ 21 , 22 ].…”

EURACAN/IASLC Proposals for Updating the Histologic Classification of Pleural Mesothelioma: Towards a More Multidisciplinary Approach

“…Some of these carry adverse prognostic significance, such as solid, pleomorphic, rhabdoid, and transitional features, whereas others are reported as favorable, such as lymphohistiocytoid, and possibly myxoid features. [8][9][10][11][12][13][14][15][16] Well-Differentiated Papillary Mesothelioma When localized, well-differentiated papillary mesotheliomas (WDPMs) (Fig. 1) are also potentially treatable by complete (pR0) resection, and carry a favorable prognosis compared to diffuse mesotheliomas.…”

“…Results: Recommendations include: (1) classification should be updated to include architectural patterns and stromal and cytologic features that refine prognostication; (2) subject to data accrual, malignant mesothelioma in situ could be an additional category; (3) grading of epithelioid malignant pleural mesotheliomas should be routinely undertaken; (4) favorable/unfavorable histologic characteristics should be routinely reported; (5) clinically relevant molecular data (programmed death ligand 1, BRCA 1 associated protein 1 [BAP1], and cyclin dependent kinase inhibitor 2A) should be incorporated into reports, if undertaken; (6) other molecular data should be accrued as part of future trials; (7) resection specimens (i.e., extended pleurectomy/decortication and extrapleural pneumonectomy) should be pathologically staged with smaller specimens being clinically staged; (8) ideally, at least three separate areas should be sampled from the pleural cavity, including areas of interest identified on pre-surgical imaging; (9) image-acquisition protocols/imaging terminology should be standardized to aid research/ refine clinical staging; (10) multidisciplinary tumor boards should include pathologists to ensure appropriate treatment options are considered; (11) all histologic subtypes should be considered potential candidates for chemotherapy; (12) patients with sarcomatoid or biphasic mesothelioma should not be excluded from first-line clinical trials unless there is a compelling reason; (13) tumor subtyping should be further assessed in relation to duration of response to immunotherapy; and (14) systematic screening of all patients for germline mutations is not recommended, in the absence of a family history suspicious for BAP1 syndrome.…”

Dataset for Reporting of Malignant Mesothelioma of the Pleura or Peritoneum: Recommendations From the International Collaboration on Cancer Reporting (ICCR)

“…However among epithelioid peritoneal malignant mesothelioma, increased mitotic count (greater than 4 in 10 HPF a ) 26 was reported as a poor prognostic indicator, and, more recently, was validated in a multi-observer study of an independent group of patients 27 , establishing a lower cut-off of 5 mitoses in 50 HPF.…”