title: Prognostic role of histological regression in primary cutaneous melanoma: a systematic review and meta-analysis.
abstract: The prognostic significance of histological regression in primary melanoma has been debated for many years. We aim to review the evidence to see how histological regression may affect prognosis. A systematic review was performed by searching in MEDLINE, Scopus and the Cochrane Library from 1 January 1966 to 1 August 2015. All studies reporting hazard ratios or data on survival and histological regression were included. Primary random-effects meta-analyses were used to summarize outcome measures. Heterogeneity was assessed using the χ2-test and I2-statistic. To assess the potential bias of small studies we used funnel plots and the Begg and Mazumdar adjusted rank correlation method. Summaries of survival outcomes were measured as hazard ratios or relative risk of death at 5 years according to the presence of histological regression of primary melanoma. In total, 183 articles were reviewed out of 1876 retrieved. Ten studies comprising 8557 patients were included. Patients with histological regression had a lower relative risk of death (0·77, 95% confidence interval 0·61-0·97) than those without. Examination of the funnel plot did not provide evidence of publication bias. The results showed that histological regression is a protective factor for survival.
authors.affiliation: Department of Public Health, University of Turin, Turin, Italy.
authors.forename: M R
authors.initials: MR
authors.lastname: Gualano
authors.affiliation: Section of Surgical Pathology, Department of Medical Sciences, University of Turin, Turin, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Osella-Abate
authors.affiliation: Department of Public Health, University of Turin, Turin, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Scaioli
authors.affiliation: Section of Dermatology, Department of Medical Sciences, University of Turin, Turin, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Marra
authors.affiliation: Department of Public Health, University of Turin, Turin, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Bert
authors.affiliation: Department of Pathophysiology and Transplantation, Section of Dermatology, Fondazione IRCCS Ca Granda, University of Milan.
authors.forename: E
authors.initials: E
authors.lastname: Faure
authors.affiliation: Section of Dermatology, Department of Medical Sciences, University of Turin, Turin, Italy.
authors.forename: E S
authors.initials: ES
authors.lastname: Baduel
authors.affiliation: Section of Dermatology, Department of Medical Sciences, University of Turin, Turin, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Balagna
authors.affiliation: Section of Dermatology, Department of Medical Sciences, University of Turin, Turin, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Quaglino
authors.affiliation: Section of Dermatology, Department of Medical Sciences, University of Turin, Turin, Italy.
authors.forename: M T
authors.initials: MT
authors.lastname: Fierro
authors.affiliation: Department of Public Health, University of Turin, Turin, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Siliquini
authors.affiliation: Section of Dermatology, Department of Medical Sciences, University of Turin, Turin, Italy.
authors.forename: S
authors.identifier: 0000-0002-0098-1406
authors.initials: S
authors.lastname: Ribero
mesh_terms: D006801:Humans; D008545:Melanoma / Q000401:mortality / Q000473:pathology*; D009365:Neoplasm Regression, Spontaneous / Q000473:pathology; D011379:Prognosis; D012307:Risk Factors; D012878:Skin Neoplasms / Q000401:mortality / Q000473:pathology*; D016019:Survival Analysis