Mucosal Melanoma of Eustachian Tube: A Case Report.

Mucosal melanoma originating from the eustachian tube is very rare, and only 15 cases were reported so far. In this study, we report a case of mucosal melanoma from the eustachian tube which was surgically managed, followed by chemoradiotherapy. A 53-year-old man presented with a history of recurrent idiopathic hemotympanum and a dark red mass in the nasopharynx protruding from the eustachian tube orifice. Under an impression of mucosal melanoma from the eustachian tube, en-bloc surgical removal was performed using the infratemporal fossa approach type C combined with a transnasal endoscopic approach followed by postoperative chemoradiotherapy. However, the disease progressed to lung metastasis, and the patient died of the disease at 13 months postoperatively. The presenting case showed a poor progression despite a margin-free surgical resection followed by chemoradiotherapy. Additional trial of new treatment options is necessary to improve the poor prognosis.

Alleviation of skin inflammation after Lin(-) cell transplantation correlates with their differentiation into myeloid-derived suppressor cells.

To understand the cellular mechanism underlying the therapeutic effects exerted by hematopoietic stem cell transplantation in the repair of tissue damage, we investigated the in vivo dynamics of bone marrow (BM) lineage-negative (Lin(-)) cells transplanted into mice with hyper sensitivity dermatitis. Longitudinal in vivo imaging and flow cytometry analyses revealed that Lin(-) cells home directly to inflamed skin within 6 h, where they undergo extensive expansion with the peak on day 14 post-transplantation, and preferential differentiation into CD11b(+)Ly6G(int)Ly6C(+) cells by day 7. Cells with phenotypic profiles of neutrophils, macrophages, and DCs appeared in inflamed skin on day 14. Progenies of transplanted Lin(-) cells showed similar kinetics of expansion and myeloid differentiation in BM. However, differentiation into CD11b(+)Ly6G(int)Ly6C(+) cells in the inflamed skin on day 7 was more skewed toward CD115(+) cells (≥60%) with immune suppressive function and higher expression levels of iNOS, arginase, and IL-10, compared with those in the BM. Transplantation of Lin(-) cells reduced the levels of Cd3 transcript and CD4(+)/CD8(+) cells in inflamed skin. These results demonstrate differentiation of transplanted Lin(-) cells into myeloid-derived suppressor cells in inflamed skin to be the basis of the alleviation of skin inflammation after Lin(-) cell transplantation.