Georgia Karpathiou1, Mousa Mobarki2, Marie Laure Stachowicz2, Sirine Hathroubi2, Arnaud Patoir3, Olivier Tiffet3, Marios Froudarakis4, Michel Peoc'h2. 1. Department of Pathology, North Hospital, University Hospital of St-Etienne, St-Etienne, France. Electronic address: gakarpath@yahoo.gr. 2. Department of Pathology, North Hospital, University Hospital of St-Etienne, St-Etienne, France. 3. Department of Thoracic Surgery, North Hospital, University Hospital of St-Etienne, St-Etienne, France. 4. Department of Pneumonology, North Hospital, University Hospital of St-Etienne, St-Etienne, France.
Abstract
BACKGROUND: Pericardial and pleural cavities produce effusions with important clinical consequences. Metastases are one of the most common etiologies of both serosal effusions. However, data regarding the type of metastatic involvement of the pleura and the pericardium are lacking. This study investigated the histologic patterns of tumors involving the two cavities to better define their pathophysiology and possible consequences in molecular diagnostics. METHODS: This was a retrospective study of patients diagnosed with pericardial (n = 75) and pleural (n = 70) metastases. Patterns of metastasis were characterized as (1) tumor cells floating inside the cavity (2) as lymphatic emboli and (3) as tumor cells frankly invading underlying fibrous tissue. Molecular analysis (EGFR, KRAS, BRAF, ALK, HER2) was performed in 44 metastases of lung adenocarcinomas. RESULTS: The two serosal membranes differed significantly (p < 0.0001) in the pattern of metastasis. The pleura showed predominantly an invasive pattern (67 [95.7%]), whereas most pericardial metastases consisted of tumor cells floating inside the cavity or as lymphatic emboli (44 [58.6%]). The origin of the primary differed marginally between the two organs. Time to diagnosis of metastasis differed between the two organs, with pleural metastases presenting later than the pericardial ones. Molecular analysis failed more often in pericardial biopsy specimens and in specimens with emboli or surface involvement. CONCLUSIONS: Although pericardium and pleura share common embryologic and histologic features and are often regarded as giving similar effusions, they differ significantly in the type of metastases involving them. This can have important consequences in histologic, cytologic, and molecular diagnostics.
BACKGROUND: Pericardial and pleural cavities produce effusions with important clinical consequences. Metastases are one of the most common etiologies of both serosal effusions. However, data regarding the type of metastatic involvement of the pleura and the pericardium are lacking. This study investigated the histologic patterns of tumors involving the two cavities to better define their pathophysiology and possible consequences in molecular diagnostics. METHODS: This was a retrospective study of patients diagnosed with pericardial (n = 75) and pleural (n = 70) metastases. Patterns of metastasis were characterized as (1) tumor cells floating inside the cavity (2) as lymphatic emboli and (3) as tumor cells frankly invading underlying fibrous tissue. Molecular analysis (EGFR, KRAS, BRAF, ALK, HER2) was performed in 44 metastases of lung adenocarcinomas. RESULTS: The two serosal membranes differed significantly (p < 0.0001) in the pattern of metastasis. The pleura showed predominantly an invasive pattern (67 [95.7%]), whereas most pericardial metastases consisted of tumor cells floating inside the cavity or as lymphatic emboli (44 [58.6%]). The origin of the primary differed marginally between the two organs. Time to diagnosis of metastasis differed between the two organs, with pleural metastases presenting later than the pericardial ones. Molecular analysis failed more often in pericardial biopsy specimens and in specimens with emboli or surface involvement. CONCLUSIONS: Although pericardium and pleura share common embryologic and histologic features and are often regarded as giving similar effusions, they differ significantly in the type of metastases involving them. This can have important consequences in histologic, cytologic, and molecular diagnostics.
Authors: Georgia Karpathiou; Jonas Benli; Anne Laure Désage; Mathilde Jacob; Olivier Tiffet; Michel Peoc'h; Marios E Froudarakis Journal: Ann Transl Med Date: 2022-04