{'fraction_non_alphanumeric': 0.047304730473047306, 'fraction_numerical': 0.033003300330033, 'mean_word_length': 5.003300330033003, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Nodular primary cutaneous melanoma is associated with PD-L1 expression

In previous studies, patients with Stage III melanomas expressing PD-L1 in more than 5% of their neoplastic cells had improved recurrence-free survival with anti-PD1 adjuvant therapy. We examined PD-L1 expression as a possible biomarker of primary cutaneous melanomas in the vertical growth phase. This was a retrospective study including 66 patients with invasive primary cutaneous melanomas. We assessed patient clinical and histopathological data and performed immunohistochemical assays with melanoma specimens from the patients to evaluate PD-L1, PD-1, CD3, CD8 and FoxP3 expression. We observed PD-L1 expression in 21% (14/66) of our samples, and this expression correlated with increased melanoma thickness (p = 0.002) and nodular-type melanoma (p = 0.001). After adjusting for tumor thickness using a logistic regression test, the association of PD-L1 with nodular-type melanoma persisted. Nodular-type melanoma was 6.48 times more likely to be positive for PD-L1 than other histological types (p = 0.014; 95% CI: 1.46–28.82). As expected, PD-L1 expression correlated with the number of PD-1-expressing cells in the tumor-infiltrating lymphocyte population (p = 0.04). No correlation with PD-L1 was observed for age, sex, tumor site, skin phototype, ulceration status, sentinel lymph node status, metastasis development or survival. Regarding the immune profile of the tumor-infiltrating lymphocytes of PD-L1-positive and -negative groups, no significant differences were observed in the numbers of CD3 +, CD8 + FoxP3-, CD8-FoxP3+ and CD8 + FoxP3+ cells by immunohistochemistry. Nodular-type melanoma is associated with PD-L1 expression and may be a suitable candidate for adjuvant therapy of primary melanomas treated with immunotherapy.