The association between pesticide use and cutaneous melanoma: a systematic review and meta-analysis

Background: The incidence of cutaneous melanoma (CM), the deadliest form of skin cancer, has gradually increased in the last decades among populations of European origin. Epidemiological studies suggested that farmers and agricultural workers are at an increased risk of CM because they were exposed to pesticides. However, little is known about the relationship between pesticides and CM. Objectives: To investigate the association between exposure to pesticides and CM by systematically reviewing the literature. Secondary aim was to determine the categories of pesticides mainly involved in CM development. Methods: A systematic review of the literature was performed up to September 2018 using MEDLINE, Embase and Web of Science. Studies assessing CM risk in licensed pesticide applicators were considered. Strict criteria were established to select independent studies and risk estimates; random effect models, taking into account heterogeneity, were applied. A pooled risk estimate for CM was calculated for the use of each type of pesticide and type of exposure. Between-study and estimate heterogeneity was assessed and publication bias investigated. Results: A total of nine studies (two case-controls and seven cohorts) comprising 184 389 unique subjects were included. The summary relative risks for the categories 'herbicides - ever exposure', 'insecticides - ever exposure', 'any pesticide - ever exposure' and 'any pesticide - high exposure' resulted 1.85 [95% confidence interval (CI): 1.01, 3.36], 1.57 (95% CI: 0.58, 4.25), 1.31 (95% CI: 0.85, 2.04) and 2.17 (95% CI: 0.45, 10.36), respectively. Herbicides and insecticides had no between-study heterogeneity (I2 = 0%), while a significant heterogeneity (I2 > 50%) was detected for the high exposure to any pesticide. No indication for publication bias was found. Conclusions: Individuals exposed to herbicides are at an increased risk of CM. Future properly designed observational studies are required to confirm this finding

Clinicopathological predictors of recurrence in nodular and superficial spreading cutaneous melanoma: A multivariate analysis of 214 cases

Abstract Background Nodular melanoma (NM) accounts for most thick melanomas and because of their frequent association with ulceration, fast growth rate and high mitotic rate, contribute substantially to melanoma-related mortality. In a multicentric series of 214 primary melanomas including 96 NM and 118 superficial spreading melanoma (SSM), histopathological features were examined with the aim to identify clinicopathological predictors of recurrence. Methods All consecutive cases of histopathologically diagnosed primary invasive SSM and NM during the period 2005–2010, were retrieved from the 12 participating Italian Melanoma Intergroup (IMI) centers. Each center provided clinico-pathological data such as gender, age at diagnosis, anatomical site, histopathological conventional parameters, date of excision and first melanoma recurrence. Results Results showed that NM subtype was significantly associated with Breslow thickness (BT) at multivariate analysis: [BT 1.01–2 mm (OR 7.22; 95% CI 2.73–19.05), BT 2.01–4 mm (OR 7.04; 95% CI 2.54–19.56), and BT > 4 mm (OR 51.78; 95% CI 5.65–474.86) (p  5 mitoses/mm2 (OR 4.87; 95% CI 1.77–13.40) (p = 0.002)]. The risk of recurrence was not significantly associated with NM histotype while BT [BT 1.01–2.00 mm (HR 1.55; 95% CI 0.51–4.71), BT 2.01–4.00 mm (HR 2.42; 95% CI 0.89–6.54), BT > 4.00 mm. (HR 3.13; 95% CI 0.95–10.28) (p = 0.05)], mitotic rate [MR > 2 mitoses/mm2 (HR 2.34; 95% CI, 1.11–4.97) (p = 0.03)] and the positivity of lymph node sentinel biopsy (SNLB) (HR 2.60; 95% CI 1.19–5.68) (p = 0.007) were significantly associated with an increased risk of recurrence at multivariate analysis. Conclusions We found that NM subtype was significantly associated with higher BT and MR but it was not a prognostic factor since it did not significantly correlate with melanoma recurrence rate. Conversely, increased BT and MR as well as SNLB positivity were significantly associated with a higher risk of melanoma recurrence

The association between pesticide use and cutaneous melanoma: a systematic review and meta-analysis

Background: The incidence of cutaneous melanoma (CM), the deadliest form of skin cancer, has gradually increased in the last decades among populations of European origin. Epidemiological studies suggested that farmers and agricultural workers are at an increased risk of CM because they were exposed to pesticides. However, little is known about the relationship between pesticides and CM. Objectives: To investigate the association between exposure to pesticides and CM by systematically reviewing the literature. Secondary aim was to determine the categories of pesticides mainly involved in CM development. Methods: A systematic review of the literature was performed up to September 2018 using MEDLINE, Embase and Web of Science. Studies assessing CM risk in licensed pesticide applicators were considered. Strict criteria were established to select independent studies and risk estimates; random effect models, taking into account heterogeneity, were applied. A pooled risk estimate for CM was calculated for the use of each type of pesticide and type of exposure. Between-study and estimate heterogeneity was assessed and publication bias investigated. Results: A total of nine studies (two case–controls and seven cohorts) comprising 184 389 unique subjects were included. The summary relative risks for the categories ‘herbicides – ever exposure’, ‘insecticides – ever exposure’, ‘any pesticide – ever exposure’ and ‘any pesticide – high exposure’ resulted 1.85 [95% confidence interval (CI): 1.01, 3.36], 1.57 (95% CI: 0.58, 4.25), 1.31 (95% CI: 0.85, 2.04) and 2.17 (95% CI: 0.45, 10.36), respectively. Herbicides and insecticides had no between-study heterogeneity (I2 = 0%), while a significant heterogeneity (I2 > 50%) was detected for the high exposure to any pesticide. No indication for publication bias was found. Conclusions: Individuals exposed to herbicides are at an increased risk of CM. Future properly designed observational studies are required to confirm this finding

No Impact of NRAS Mutation on Features of Primary and Metastatic Melanoma or on Outcomes of Checkpoint Inhibitor Immunotherapy: An Italian Melanoma Intergroup (IMI) Study

Aims: It is debated whether the NRAS-mutant melanoma is more aggressive than NRAS wildtype. It is equally controversial whether NRAS-mutant metastatic melanoma (MM) is more responsive to checkpoint inhibitor immunotherapy (CII). 331 patients treated with CII as first-line were retrospectively recruited: 162 NRAS-mutant/BRAF wild-type (mut/wt) and 169 wt/wt. We compared the two cohorts regarding the characteristics of primary and metastatic disease, disease-free interval (DFI) and outcome to CII. No substantial differences were observed between the two groups at melanoma onset, except for a more frequent ulceration in the wt/wt group (p = 0.03). Also, the DFI was very similar in the two cohorts. In advanced disease, we only found lung and brain progression more frequent in the wt/wt group. Regarding the outcomes to CII, no significant differences were reported in overall response rate (ORR), disease control rate (DCR), progression free survival (PFS) or overall survival (OS) (42% versus 37%, 60% versus 59%, 12 (95% CI, 7–18) versus 9 months (95% CI, 6–16) and 32 (95% CI, 23–49) versus 27 months (95% CI, 16–35), respectively). Irrespectively of mutational status, a longer OS was significantly associated with normal LDH, <3 metastatic sites, lower white blood cell and platelet count, lower neutrophil-to-lymphocyte (N/L) ratio. Our data do not show increased aggressiveness and higher responsiveness to CII in NRAS-mutant MM

No Impact of NRAS Mutation on Features of Primary and Metastatic Melanoma or on Outcomes of Checkpoint Inhibitor Immunotherapy: An Italian Melanoma Intergroup (IMI) Study

Aims: It is debated whether the NRAS-mutant melanoma is more aggressive than NRAS wildtype. It is equally controversial whether NRAS-mutant metastatic melanoma (MM) is more responsive to checkpoint inhibitor immunotherapy (CII). 331 patients treated with CII as first-line were retrospectively recruited: 162 NRAS-mutant/BRAF wild-type (mut/wt) and 169 wt/wt. We compared the two cohorts regarding the characteristics of primary and metastatic disease, disease-free interval (DFI) and outcome to CII. No substantial differences were observed between the two groups at melanoma onset, except for a more frequent ulceration in the wt/wt group (p = 0.03). Also, the DFI was very similar in the two cohorts. In advanced disease, we only found lung and brain progression more frequent in the wt/wt group. Regarding the outcomes to CII, no significant differences were reported in overall response rate (ORR), disease control rate (DCR), progression free survival (PFS) or overall survival (OS) (42% versus 37%, 60% versus 59%, 12 (95% CI, 7–18) versus 9 months (95% CI, 6–16) and 32 (95% CI, 23–49) versus 27 months (95% CI, 16–35), respectively). Irrespectively of mutational status, a longer OS was significantly associated with normal LDH, <3 metastatic sites, lower white blood cell and platelet count, lower neutrophil-to-lymphocyte (N/L) ratio. Our data do not show increased aggressiveness and higher responsiveness to CII in NRAS-mutant MM

Supplementary Material for: Multiple Lymph Node Basin Drainage in Trunk Melanoma Is Not Associated with Survival of Sentinel Lymph Node-Positive Patients

<i>Objectives:</i> This study was aimed at investigating the prognostic role of multiple lymph node basin drainage (MLBD) in patients with positive sentinel lymph node (SLN) biopsy. <i>Background:</i> MLBD is frequently observed in patients with trunk melanoma undergoing SLN. The prognostic value of MLBD in SLN-positive patients is still debated. <i>Methods:</i> Retrospective data from 312 trunk melanoma patients with positive SLN biopsy (1991-2012) at 6 Italian referral centres were gathered in a multicentre database. MLBD was defined at preoperative lymphoscintigraphy. Clinical and pathological data were analysed for their association with disease-free interval (DFI) and disease-specific (DSS) survival. <i>Results:</i> MLBD was identified in 34.6% of patients (108/312) and was significantly associated with >1 positive SLN (37 vs. 15.2%; <i>p</i> < 0.001) and with >1 positive lymph node (LN) after complete lymph node dissection (CLND) (50.9 vs. 34.8%; <i>p</i> = 0.033). No differences were observed according to drainage pattern in patients who had negative and positive non-SLN at CLND. MLBD was not associated with either DFI or DSS. Multivariate analyses showed that tumour thickness, ulceration, and number of metastatic LNs were associated with worse DFI and DSS, while regression confirmed its protective role in survival. <i>Conclusion:</i> In positive SLN patients, MLBD has no association with survival, which is mainly related to American Joint Committee on Cancer (AJCC) prognostic factors. Since the overall number of positive LNs drives the prognosis, the importance of a CLND in all the positive basins is confirmed