In Lancet Oncology this week, researchers in Germany present a pathological study on the prevalence of mismatch repair-deficient crypt foci in Lynch syndrome, an inherited tumor predisposition. The team examined samples from small and large bowel cancer resections and analyzed non-tumor mucosa from carriers of a Lynch syndrome mutation and control patients without Lynch syndrome for expression of DNA mismatch repair genes. They detected 20 crypt foci with no mismatch repair gene expression in the non-cancerous mucosa from Lynch syndrome patients and no mismatch repair-deficient crypt foci in the mucosa from control patients. "We identified a novel type of lesion, the MMR-deficient crypt focus, as the manifestation of biallelic MMR gene inactivation in Lynch syndrome," the authors write. "The abundance of MMR-deficient crypt foci indicates a high frequency of biallelic MMR gene inactivation, which is in sharp contrast with the low number of clinically manifest cancers in Lynch syndrome. This discrepancy suggests that most MMR-deficient crypt foci do not progress to cancer."
In NEJM this week, researchers in The Netherlands report on the efficacy of preoperative chemoradiotherapy for esophageal or junctional cancer. The team randomly assigned 366 patients with resectable tumors —adenocarcinoma, squamous-cell carcinoma, or large-cell undifferentiated carcinoma — to receive either surgery alone, or carboplatin and paclitaxel with concurrent radiotherapy before surgery. They found that the preoperative chemoradiotherapy improved overall survival significantly, with an acceptable rate of adverse events. "Median overall survival was 49.4 months in the chemoradiotherapy-surgery group versus 24.0 months in the surgery group," the authors write.
Also in NEJM this week, Yale University School of Public Health's Vincent DeVita, Jr., and George Washington University School of Medicine's Steven Rosenberg describe the past 200 years of cancer research, since NEJM was first published. "Cancer has gone from a black box to a blueprint," they write in a review article. Early discoveries by cancer researchers "gave birth to the molecular revolution and the biotechnology industry," they add. "They also paved the way for the sequencing of the genome." Many advancements have been made in cancer treatment and prevention, and survival rates have improved significantly in that time, DeVita and Rosenberg write. In the future, they add, "the economic and social consequences of converting cancer into a curable or chronic disease will be both gratifying and daunting."