More lymphoid follicles: what does it mean for patients?

This study developed a new method for assessing Crohn’s-like lymphoid reaction (CLR) in patients with colorectal cancer. It also examined if CLR can be useful for predicting patient outcome.

Patients with colorectal cancer can have inflammation in the bowel which is similar to inflammation in patients with Crohn’s disease (Crohn’s-like lymphoid reaction; CLR). In patients with CLR there are increased masses of cells of the immune system (lymphoid follicles) around the tumor.

It has previously been reported that increased inflammatory immune cells in the bowel is linked to better disease outcome (prognosis) for patients with colorectal cancer. Therefore, it would be beneficial to develop a scoring system for CLR and investigating if CLR can predict better disease outcome.

567 patients with colorectal cancer were included in this study. Blood samples and pieces of bowel (biopsies) were collected from each patient. 149 of the patients were also subdivided based on treatment received before surgery (117 patients in group A had no treatment, 32 patients in group B had radiotherapy or chemotherapy).

The patients' bowel samples were analyzed and the density of lymphoid follicles (the number of immune cells in a given space) was calculated. Higher density of lymphoid follicles (more than 0.38 follicles per mm) was linked to lower tumor stage and no pre-surgery treatment.

Patients with higher lymphoid follicle density (high CLR) had a better chance of survival compared to patients with low CLR (less than 0.38 follicles per mm). High CLR density was also predictive of better disease outcome.

The authors concluded that lymphoid follicles have properties that help decrease the impact of colorectal tumors. They also suggest that evaluating the CLR density may be useful for predicting patient outcome.