Summary We describe two patients with BRAF‐mutated melanoma of the epithelioid cell type arising from primary acquired melanosis with severe atypia of the right bulbar conjunctiva. Patient 1 was a 71‐year‐old Japanese man. After adjuvant cryotherapy and enucleation of the right eyeball, therapy with vemurafenib was administered for a distant metastasis to a lumbar vertebra, accompanied by erythema multiforme and two keratinous tumours. The patient died due to metastases to the liver and multiple vertebrae, despite therapy with nivolumab and combination therapy with dabrafenib plus trametinib. Patient 2 was a 72‐year‐old Japanese man. After adjuvant cryotherapy, periodic mitomycin C eye drops, and excision of the superficial portion of the right parotid gland and the dissection of cervical lymph nodes, he was treated with adjuvant combination therapy with dabrafenib plus trametinib. Dermatologists should be familiar with BRAF‐mutated conjunctival melanoma, which is usually located on the bulbar conjunctiva and associated with more frequent distant metastasis.

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A 65‐year‐old Japanese man presented with a dome‐shaped nodule, the base of which was contiguous with a dull brown plaque, on the left leg. After local excision of the cutaneous lesion and left inguinal lymph node dissection, several dermal and subcutaneous nodules developed successively on the left lower extremity. Hematoxylin–eosin staining of the primary cutaneous lesion demonstrated uniform neoplastic cells arranged in a trabecular pattern extending from the dermis to subcutis. Mitotic figures were abundant. Although the overlying epidermis was substantially intact, the Merkel cells had invaded the epidermis, resulting in Pautrier‐like microabscesses. The hyperplastic epidermis adjacent to the nodule consisted of abnormally growing atypical keratinocytes. The enlarged left inguinal lymph node and successive secondary nodules contained Merkel cells similar to those in the primary nodule. Immunohistochemically, most tumor cells were positive for CAM5.2, synaptophysin, chromogranin A, CD56 and vimentin. The tumor cells in the left inguinal lymph node were positive for CAM5.2, synaptophysin and cytokeratin 20 but negative for CM2B4, and less than 1% of the cells expressed programmed cell death ligand 1. The patient was treated with avelumab, which showed significant efficacy against the in‐transit recurrence. Two months later, all nodules had disappeared completely. We describe a case of in‐transit recurrence of Merkel cell carcinoma that was associated histologically with Bowen's disease and was successfully treated with avelumab. Although accumulation of additional cases is needed, avelumab therapy may be a useful treatment for in‐transit recurrence of Merkel cell carcinoma.