Case report: Is severe toxicity the price to pay for high sensitivity to checkpoint inhibitors immunotherapy in desmoplastic melanoma?

Background: Desmoplastic melanoma (DM) is a rare subtype of melanoma characterized by high immunogenicity which makes it particularly suitable for immune checkpoint inhibitors (ICIs) treatment. Case presentation: We report the case of a 53-year-old man with metastatic DM successfully treated with the combination of anti-CTLA-4 and anti-PD-1 antibodies, who developed serious immune-related adverse events (irAEs). The primary tumor was characterized by absent PD-L1 expression and no-brisk lymphocytes infiltration. NGS showed absence of BRAF mutation, a high tumor mutational burden, and an UV-induced DNA damage signature. Metastatic lesions regressed rapidly after few cycles of ICIs until complete response, however the patient developed serious irAEs including hypothyroidism, adrenal deficiency, and acute interstitial nephritis which led to the definitive suspension of treatment. Currently, the patient has normal renal functionality and no disease relapse after 26 months from starting immunotherapy, and after 9 months from its definitive suspension. Conclusion: Efficacy and toxicity are two sides of the same coin of high sensitivity to ICIs in DM. For this reason, these patients should be closely monitored during ICIs therapy to promptly identify serious side effects and to correctly manage them.

Calciphylaxis in a patient with POEMS syndrome without renal failure and/or hyperparathyroidism. A case report.

POEMS (Crow-Fukase) syndrome is a rare plasma cell lymphoproliferative disorder associated with polyneuropathy (P), organomegaly (O), endocrinopathy (E), monoclonal (M) gammopathy and skin (S) abnormalities. The latter are usually not specific and include hyperpigmentation, hypertrichosis, cutaneous angioma and skin-thickening. A 45-year-old Italian woman was admitted to hospital because of muscle weakness, marked fatigue and paresthesia of the upper and lower extremities. Two and a half years earlier, a POEMS syndrome had been diagnosed on the basis of a history of organomegaly and mild lymphadenopathy, IgA-lambda monoclonal gammopathy, hypothyroidism, severe lower and upper limb sensory-motor peripheral neuropathy and a single osteosclerotic lesion in the left humerus. Eight weeks later, she developed skin lesions bioptically shown to be due to calciphylaxis-induced cutaneous vasculitis. To our knowledge, this is the first case of POEMS syndrome with this peculiar type of vasculitis. The absence of predisposing conditions, namely renal failure, hyperparathyroidism or clotting disorders renders the pathogenetic mechanism(s) of this severe type of vasculitis more intriguing.