Chatzopoulos, Kyriakos

AimsPulmonary chondromas, which are rare cartilaginous neoplasms that often arise in the setting of Carney triad, are morphologically similar to pulmonary hamartomas, which are much more common. There is evidence that succinate dehydrogenase (SDH) deficiency drives neoplasia in patients with Carney triad, and SDHB immunohistochemistry can be used as a surrogate marker to detect SDH deficiency. The aim of this study was to investigate the utility of SDHB immunohistochemistry in distinguishing pulmonary chondromas from hamartomas.Methods and resultsImmunohistochemistry for SDHB (clone 21A11AE7) was performed on histological sections from six cases of pulmonary chondroma and 33 cases of pulmonary hamartoma. SDHB expression was retained in all 33 pulmonary hamartomas, and lost in the majority of evaluable chondromas (five of six). Of the five patients with chondromas showing SDHB loss, four had definitive Carney triad. Most patients with pulmonary hamartomas were older males with small solitary masses, whereas chondromas often presented as multiple masses in young females.ConclusionLoss of SDHB immunohistochemical expression can be useful for differentiating pulmonary chondromas from hamartomas, and potentially identifying patients with Carney triad.

Abstract In patients with metastatic melanoma, high blood levels of galectin‐9 are correlated with worse overall survival and a bias towards a Th2 inflammatory state supportive of tumor growth. Although galectin‐9 signaling through TIM3 on T cells has been described, less is known about the interaction of galectin‐9 with macrophages. We aimed to determine whether galectin‐9 is a binding partner of CD206 on macrophages and whether the result of this interaction is tumor‐supportive. It was determined that incubation of CD68 + macrophages with galectin‐9 or anti‐CD206 blocked target binding and that both CD206 and galectin‐9 were detected by immunoprecipitation of cell lysates. CD206 and galectin‐9 had a binding affinity of 2.8 × 10 −7 m . Galectin‐9 causes CD206 + macrophages to make significantly more FGF2 and monocyte chemoattractant protein (MCP‐1), but less macrophage‐derived chemokine (MDC). Galectin‐9 had no effect on classical monocyte subsets, but caused expansion of the non‐classical populations. Lastly, there was a positive correlation between increasing numbers of CD206 macrophages and galectin‐9 expression in tumors, and high levels of CD206 macrophages correlated negatively with melanoma survival. These results indicate that galectin‐9 binds to CD206 on M2 macrophages, which appear to drive angiogenesis and the production of chemokines that support tumor growth and poor patient prognoses. Targeting this interaction systemically through circulating monocytes may therefore be a novel way to improve local anti‐tumor effects by macrophages. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.