[Primary central nervous system lymphoma following immunotherapy for metastatic melanoma]. / Lymphome cérébral primitif après immunothérapie d'un mélanome métastatique.

BACKGROUND: Anti-PD-1 and anti-CTLA-4 monoclonal antibodies are used in melanoma, while anti-PD-1 are also used in Hodgkin's lymphoma. Primary central nervous system lymphoma is a rare form of non-Hodgkin's lymphoma with few effective treatments. However, several recent studies have reported multiple cases of non-Hodgkin's lymphoma and primary central nervous system lymphoma treated by anti-PD-1 antibodies with favourable responses. PATIENTS AND METHODS: This study focuses on the case of a 59-year-old man with metastatic melanoma treated by immunotherapy (anti-CTLA-4 followed by anti-PD-1). He underwent 28 courses of therapy with pembrolizumab. Treatment was stopped after clinical and radiological remission. The patient presented left hemiparesis and a primary central nervous system lymphoma was diagnosed two months after discontinuation of immunotherapy. He started urgent high-dose methotrexate chemotherapy but without significant results. Despite second-line chemotherapy with R-ICE (rituximab-ifosfamide, carboplatin and etoposide), the patient died. DISCUSSION: Several hypotheses may be advanced regarding a possible relationship between immunotherapy and the occurrence of this primary central nervous system lymphoma. The lymphoma may have been pre-existing and controlled by immunotherapy, but progressing rapidly after treatment, or it may have been induced by the immunotherapy. However, immunotherapy may have played no role; the relationship between melanoma and lymphoma is well known. CONCLUSION: While immunotherapy cannot be unequivocally incriminated in primary central nervous system lymphoma, this case raises many questions about the imputability of immunotherapy in the occurrence of secondary cancers, including lymphomas.

Clinical and immunological features and outcome of anti-p200 pemphigoid.

BACKGROUND: Anti-p200 pemphigoid is a rare autoimmune blistering disease (AIBD) of the dermoepidermal junction, characterized by autoantibodies to laminin γ1. The clinical course of anti-p200 pemphigoid in patients remains poorly investigated. OBJECTIVES: We aimed to describe the clinical and immunological features and the course of a series of patients with anti-p200 pemphigoid. METHODS: We conducted a retrospective study by immunoblotting detection of sera on 200-kDa dermal protein extracts from the register of the French reference centre for AIBD. We recorded the clinical and immunological features and the course of patients. RESULTS: A total of 14 patients with a mean age 81·6 ± 6·5 years were included. Only one patient had an associated neurological condition and one had psoriasis. Twelve patients had atypical clinical presentation, including eczematous, urticarial, prurigo-like, dyshydrosis-like and rosette-like skin lesions. Eight patients (57%) had mucosal involvement. Immunoblot analysis of sera on dermal and epidermal extracts showed a 200-kDa band in 14 and 10 cases, respectively. All eight of the sera tested by enzyme-linked immunosorbent assay detected recombinant human laminin γ1. Disease control was obtained in six of nine patients treated with topical corticosteroids, and four of five patients who received systemic treatment. Seven patients relapsed (50%) and five patients (36%) died during the median follow-up time of 12·6 months. At the end of the study, only one of the nine living patients was in complete remission off therapy. CONCLUSIONS: Many patients with anti-p200 pemphigoid had heterogeneous clinical presentation and a more severe prognosis than previously suspected.