Mesothelioma and Colorectal Cancer: Report of Four Cases with Synchronous and Metachronous Presentation.

There is evidence that asbestos could play a role in the carcinogenesis of digestive cancers. The presence of asbestos fibres in histological samples from gastric, biliary, colon cancers has been reported, but the mechanism is still controversial. It has been hypothesised that asbestos reaches these sites, especially through contaminated water; however, some experimental studies have shown that the inhaled fibres are mobile, so they can migrate to many organs, directly or via blood and lymph flow. We report four unusual cases of colorectal cancers in patients with a long history of asbestos exposure who also developed synchronous or metachronous mesothelioma. We evaluated the roles of BRCA associated protein-1 (BAP1) and cyclin-dependent kinase inhibitor 2A (CDKN2A) in colon cancer and mesothelioma to support the hypothesis that BAP-1 and CDKN2A are tumour suppressor genes involved in disease progression, recurrence, or death in both digestive cancers and mesothelioma. Potentially, these markers may be used as predictors of worse prognosis, but we also stress the importance of clinical surveillance of exposed patients because asbestos could induce cancer in any organ.

Adverse Prognostic Impact of Transitional and Pleomorphic Patterns in Pleural Nonepithelioid Mesothelioma: Insights From Comprehensive Analysis and Reticulin Stain.

CONTEXT.­: Mesothelioma subtyping into epithelioid and nonepithelioid categories plays a crucial role in prognosis and treatment selection, with emerging recognition of the impact of various histologic patterns. OBJECTIVE.­: To investigate the prognostic implications of transitional and pleomorphic patterns in sarcomatoid mesothelioma. DESIGN.­: A total of 132 mesothelioma cases (87 biphasic, 45 sarcomatoid) were analyzed. Histologic slides were assessed, treatment data collected, and cases categorized into predominant epithelioid or sarcomatoid patterns. The sarcomatoid mesotheliomas were classified into usual, pleomorphic, and transitional patterns, with reticulin staining for the latter. Statistical analysis included Cox regression and Kaplan-Meier methods. RESULTS.­: Younger age (P = .02) and receiving therapy (P < .001) correlated with improved survival for both histotypes. Advanced stage was associated with shorter survival in sarcomatoid cases (P = .02). Predominant epithelioid pattern in biphasic cases led to longer survival (P < .001). Transitional and pleomorphic patterns were indicative of worse prognosis, with significantly lower survival in cases with both patterns than with usual sarcomatoid (P = .046). Multivariate analysis identified independent survival factors, including predominant epithelioid component in biphasic mesothelioma (P = .001) and chemotherapy (P < .001). CONCLUSIONS.­: Histologic subtyping in mesothelioma plays a pivotal role in prognosis. Transitional and pleomorphic patterns, even in low percentages, indicate poorer outcomes. This study highlights the need for standardized diagnostic support and suggests the potential utility of histochemical staining in identifying more aggressive morphologic aspects. Recognizing the significance of these patterns can guide treatment decisions and patient care strategies.

Poorly Differentiated Cutaneous Squamous Cell Carcinoma (cSCC) or Lymphoepithelioma-like Carcinoma of the Skin (LELCS) with Squamous Pearls: A Case Presentation with Emphasis on Histomorphological Features and Classification Debates.

Lymphoepithelioma-like carcinoma of the skin (LELCS) is a rare primary skin cancer, with an annual incidence of 1/100,000 and about 85 cases published in the literature. It is considered the cutaneous counterpart of undifferentiated nasopharyngeal carcinoma (UNC, Schmincke-Regaud tumor) but has no association with EBV. We present an interesting case with features of LELCS in a 93-year-old man, right frontal-orbital region, diagnosed histologically and with immunohistochemical features. We also emphasize contrasting morphologic features for correct nosographic classification and address current issues, suggesting potential insights. Finally, we briefly reviewed other cases described in the literature.