Perineural invasion signals poor prognosis in gastric cancer

Last Updated: 2016-08-15

By Reuters Staff

NEW YORK (Reuters Health) - Perineural invasion (PNI) in locally advanced gastric cancer is associated with worse outcomes in patients who undergo gastrectomy and adjuvant chemotherapy, according to Italian researchers.

In a paper online June 29 in The American Journal of Surgery, Dr. Giammauro Berardi of the University of Rome and colleagues note that "understanding of PNI pathogenesis is still in its infancy."

However, they add, PNI is "associated with a more aggressive tumor and with a poorer prognosis in several malignancies such as head and neck tumors and prostate cancer."

To examine the situation in stage II/III gastric cancer, the researchers reviewed the records of 103 patients treated over 10 years. All underwent gastrectomy and modified D2 lymphadenectomy with curative intent combined with adjuvant chemotherapy. Median follow-up was 26 months.

Forty-seven tumor specimens (45.6%) were positive for PNI, the team found.

Overall survival was 81% at one year and 42% at five years. Subgroup analysis showed that patients with positive PNI had a significantly worse five-year actuarial overall survival (59% vs. 19%) and disease-free survival (69% vs. 22%) compared to patients without PNI.

Multivariate analysis showed that age, number of positive lymph nodes, T stage and PNI were independently associated with overall survival. Although in univariate analysis these and a number of other factors showed an association with disease-free survival, in multivariate analysis, only PNI had an independent association.

The researchers concede that the study was retrospective, small and conducted at a single center and call for "a large-scale prospective validation study" to confirm the results.

Nevertheless, they conclude that PNI should be incorporated into the post-operative staging system "for planning follow-up after surgery." They also propose "more aggressive post-operative therapies in PNI positive patients."

Dr. Berardi did not respond to requests for comments.

SOURCE: http://bit.ly/2bhSXS2

Am J Surg 2016.