Melanoma and Immune Checkpoint Inhibitors.

PURPOSE OF REVIEW: Prognosis of patients with advanced melanoma is dismal with a median overall survival of about 8 months and 5-year overall survival from a diagnosis of metastatic disease of roughly 10%. However, immune checkpoint inhibitors have brought indispensable benefits to melanoma patients. Here we will review the recent clinical efficacy and adverse events of immune checkpoint inhibitors for melanoma patients. RECENT FINDINGS: The immune checkpoint inhibitors increase confirmed objective response and prolong progression-free and overall survival of the afflicted patients in association with maintaining their quality of life. Although diverse immune-related adverse events occur, most of them are manageable by appropriate immunomodulating agents. Clinical efficacy of immune checkpoint inhibitors continues even after discontinuation of drugs. Compared with conventional therapeutic options, the immune checkpoint inhibitors appear to prolong the survival of patients with advanced melanoma. Further clinical trials are warranted to determine whether their combinatory use with other treatment options may augment benefits or not.

Acral lentiginous melanoma: who benefits from sentinel lymph node biopsy?

BACKGROUND: There are significant clinicopathological, genetic, and biological differences between acral lentiginous melanoma (ALM) and other types of melanoma. OBJECTIVE: We sought to investigate the use of sentinel lymph node (SLN) biopsy for patients with ALM. METHODS: This was a retrospective review of 116 patients with primary ALM. Melanoma-specific and disease-free survival were estimated using the Kaplan-Meier method, together with multivariate analyses using the Cox proportional hazards regression model. RESULTS: All patients were Japanese (48 male and 68 female). Metastases in SLN were noted in 13 of 84 patients who underwent SLN biopsy. No patients with thin ALM (≤1 mm) and only 2 patients with nonulcerated ALM had tumor-positive SLN. Patients with positive SLN had significantly shorter melanoma-specific survival (5-year survival rate, 37.5% vs 84.3%; P < .0001) and disease-free survival (5-year survival, 37.5% vs 77.9%; P = .0024). Among patients with thick (>1 mm) ALM, the influence of SLN positivity on melanoma-specific survival was increased (5-year survival, 22.7% vs 80.8%; P = .0005). LIMITATIONS: This was a retrospective study and had a small sample size. CONCLUSIONS: SLN biopsy should be considered for patients with thick or ulcerated ALM. For patients with thin or nonulcerated ones, it may be of limited importance.

Overexpression of cathepsin D in malignant melanoma.

Cathepsin D is an aspartic lysosomal endopeptidase present in most mammalian cells. Overexpression of cathepsin D is associated with the progression of several human cancers including melanoma. We examined the expression levels of cathepsin D in 20 primary malignant melanomas, 20 metastatic malignant melanomas, 20 benign nevus pigmentosus and 10 normal skin samples in Japanese. In normal skin, granular or dotted pattern of positive staining was observed along the granular layer of epidermis and hair follicle with apparent moderate to strong staining in sebaceous and eccrine glands. The percent positivity and staining intensity of cathepsin D in primary and metastatic malignant melanomas were significantly higher than that of nevus pigmentosus. Moreover, the expression levels of cathepsin D in metastatic malignant melanomas were significantly higher than those of primary malignant melanomas. Data from our and previous reports strongly supports a notion that the upregulation of cathepsin D may be critically involved in the malignant transformation and progression of melanocytic tumors.

Acral lentiginous melanoma versus other melanoma: A single-center analysis in Japan.

We summarize herein our 14-year experience of conventional treatment outcomes before the era of molecular-targeted therapy and immunotherapy. Specifically, we conducted a retrospective review of our 252 patients with primary cutaneous melanoma (acral lentiginous melanoma [ALM], n = 121; non-acral lentiginous melanoma [non-ALM], n = 131), and compared the prognostic factors between ALM and non-ALM. Melanoma-specific survival and disease-free survival were estimated using the Kaplan-Meier method. Regarding the results, all patients were Japanese (106 male and 146 female), with a mean age of 60.1 years. Among ALM patients, age was elder and primary tumor size was larger than non-ALM. As for tumor thickness, in situ lesions were more frequently observed in ALM. There was no significant difference in the distribution of tumor thickness between the two groups when excluding the in situ lesions. For treatment of the primary melanoma, 248 patients (98.4%) had undergone curative surgical excision and 120 patients with more than 1 mm or ulcerated melanoma had undergone sentinel lymph node biopsy. Patients with systemic metastasis primarily underwent dacarbazine-based chemotherapy. The Kaplan-Meier survival curves revealed no significant difference in melanoma-specific survival and disease-free survival between those with ALM and non-ALM. The results also showed that both ALM and non-ALM, when they initially metastasize, first affect the regional lymph nodes. Incisional biopsy was not an adverse prognostic factor. These results suggest that ALM does not differ in its biological behavior from non-ALM, so we can consider ALM as being equivalent to non-ALM. The initial treatment for ALM and non-ALM can involve the same strategy.