ADC as a predictor of pathologic response to neoadjuvant therapy in esophageal cancer: a systematic review and meta-analysis.

OBJECTIVE: Diffusion-weighted magnetic resonance imaging (DWI) is part of clinical practice. The aim of this study was to evaluate the role of apparent diffusion coefficient (ADC) as a predictor of pathologic response to neoadjuvant therapy (nCRT) in patients with esophageal cancer (EC). METHODS: The MEDLINE, Embase, and Google Scholar databases were systematically searched for studies using ADC to evaluate response to neoadjuvant therapy in patients with EC. Methodological quality of the studies was evaluated with the QUADAS tool. Data from eligible studies were extracted and evaluated by two independent reviewers. Meta-analyses were performed comparing mean ADC values between responders and non-responders to nCRT in three different scenarios: baseline (BL) absolute values; percent change between intermediate (IM) values and BL; and percent change between final follow-up (FU) value and baseline BL. RESULTS: Seven studies (n = 158 patients) were included. Responders exhibited a statistically significant percent increase in ADC during nCRT (mean difference [MD] 21.06%, 95%CI = 13.04-29.09; I2 = 49%; p = 0.12). A similar increase was identified in the complete pathologic response (pCR) versus non-complete pathologic response (npCR) subgroup (MD = 25.68%, 95%CI = 18.87-32.48; I2 = 0%; p = 0.60). At the end of treatment, responders also exhibited a statistically significant percent increase in ADC (MD = 22.49%, 95%CI = 9.94-35.05; I2 = 0%; p = 0.46). BL ADC was not associated with any definition of pathologic response (MD = 0.11%, 95%CI = - 0.21-0.42; I2 = 85%; p < 0.01). CONCLUSION: These results suggest that ADC can be used as a predictor of pathologic response, with a statistically significant association between percent ADC increase during and after treatment and pCR. ADC may serve as a tool to help in guiding clinical decisions. KEY POINTS: • DWI is routinely included in MRI oncological protocols. • ADC can be used as a predictor of pathologic response, with a statistically significant association between percent ADC increase during and after treatment and pCR.

Osteoporose e álcool / Osteoporosis and alcohol

A osteoporose é classificada em primária e secundária (quando é uma manifestação de um processo patológico claramente identificado). Dentre as formas secundárias encontra-se a osteoporose induzida pelo álcool. O álcool torna os pacientes mais suscetíveis a fraturas em decorrência de seus efeitos diretos e indiretos sobre o metabolismo ósseo, bem como em razão de outros efeitos adversos do álcool com alterações no equilíbrio e no sistema nervoso periférico, com maior tendência a quedas. Entretanto, estes efeitos maléficos do álcool não estão presentes quando a ingesta é pequena, casos em que pode haver mesmo um efeito protetor de osteopenia. Os efeitos deletérios do álcool sobre o metabolismo ósseo são, pelo menos em parte, reversíveis através da abstinência, consistindo este o único tratamento específico nesta doença. Neste artigo os autores fazem uma revisão sobre os efeitos diretos e indiretos do álcool no metabolismo ósseo, reversibilidade destes efeitos, influência do sexo, idade e raça dos pacientes, bem como efeitos benéficos do álcool na osteoporose