Prognostic models based on lymph node density for primary gastrointestinal melanoma: a SEER population-based analysis

Objective
This study aimed to construct prognostic models to predict the overall survival (OS) and cancer-specific survival (CSS) of patients with primary gastrointestinal melanoma (PGIM).

Design
An observational and retrospective study.

Setting
Data were obtained from the Surveillance, Epidemiology and End Results (SEER) programme database, encompassing a broad geographical and demographic spectrum of patients across the USA.

Participants
A total of 991 patients diagnosed with PGIM were included in this study.

Methods
A total of 991 patients with PGIM were selected from the SEER database. They were further divided into a training cohort and a validation cohort. Independent prognostic factors were identified by Cox regression analysis. Two prognostic models were constructed based on the results of multivariable Cox regression analysis. The concordance index (C-index) and area under the time-dependent receiver operating characteristic curve (time-dependent AUC) were used to evaluate the discriminative ability. Calibration curves were plotted to evaluate the agreement between the probability as predicted by the models and the actual probability. Risk stratification was developed given the model.

Results
By the multivariable Cox regression analysis, we identified four independent risk factors (age, stage, lymph node density and surgery) for OS, and three independent risk factors (stage, lymph node density and surgery) for CSS, which were used to construct prognostic models. C-index, time-dependent AUC, calibration curves and Kaplan-Meier curves of risk stratification indicated that these two models had good discriminative ability, predictive ability as well as clinical value.

Conclusions
The prognostic models of OS and CSS had satisfactory accuracy and were of clinical value in evaluating the prognosis of patients with PGIM.

Leggi
Ottobre 2023

The Gut Microbiome in Melanoma

The gut contains approximately 100 trillion commensal microorganisms, including viruses, archaea, bacteria, and unicellular eukaryotes that influence the development and function of the human neurological, immunological, and digestive systems from birth through adulthood. These collective microbes and their genes comprise the gut microbiome, which has gained clinical interest in many specialties as a diagnostic and potential therapeutic tool for several diseases and malignant neoplasms. The bacterial component of the gut microbiome is the most well-characterized and can be studied in a culture-independent manner using 16S ribosomal RNA sequencing. Alpha diversity describes the richness (number of unique species) in a single sample. Beta diversity describes differences between population samples. Dysbiosis describes a deviation from normal composition or metabolic activity.

Leggi
Ottobre 2023