Brightfield Multiplex Immunohistochemistry Assay for PD-L1 Evaluation in Challenging Melanoma Samples.

Targeting the PD1/PD-L1 immune checkpoint pathway has rapidly become a therapeutic strategy for melanoma patients. Indeed, the quantification of PD-L1 expression by immunohistochemistry (IHC) in melanoma samples is already required, in some contexts, to allow access to anti-PD-1/PD-L1 immunotherapy. Despite a rising demand for PD-L1 testing, paralleling increasing cumulative experience in its assessment and quantification, it is fair to recognize that PD-L1 evaluation in melanoma samples still presents some critical issues. The aim of this technical report is to develop and validate a multiplex double staining protocol for PD-L1/SOX10 in Ventana Benchmark Ultra for routine practice. Our results show that double labeling provides the necessary tools to identify PD-L1 + melanoma cells clearly. The simultaneous visualization of 2 different proteins targets allows the topographical relationship between the 2 labeling to be evaluated within the context of the tissue morphology. Future studies are needed to test this technique's real-world applicability and effectiveness in implementing interpathologist agreement.

Head and neck melanoma: the eyelid region has a better prognosis and easier management. A retrospective survey and systematic review.

Eyelid melanoma (EM) is a malignant neoplasm accounting for around 1% of eyelid malignancies. Because of its rarity, most of our knowledge of EM is currently based on studies of cutaneous melanomas located elsewhere. Accordingly, this study aimed to specifically evaluate EM characteristics, management strategies, and prognosis. A retrospective study was carried out on patients diagnosed with EM at Careggi University Hospital, Florence between May 2012 and May 2022. In addition, a systematic review of relevant literature was conducted, encompassing studies published from 2013 to 2023. Clinical, histopathological, therapeutical, and prognostic data were analyzed to assess the metastasis rate and the 5-year survival rate of patients with EM. Separate data were extracted for in situ and invasive disease. Our original study included 19 patients diagnosed with EM with a 5-year survival rate of 100% for in situ and 83.3% for invasive EM. The literature review identified five poorly detailed large database reviews and 14 original studies on EM with an overall 5-year survival rate of 79.7%. The present research indicates that EM is a challenging malignancy, but has a relatively better prognosis and easier management than other melanomas of the head and neck region. These are probably related to the anatomical location which leads to early diagnosis. Therefore, EM should be considered as a specific disease requiring dedicated treatment. Based on the personal authors' experience and comprehensive overview of the current knowledge, a dedicated protocol is proposed.