Lymph Node Status Predicted Survival After Chemo for Esophagogastric Cancer

June 23, 2016

Lymph node status after undergoing neoadjuvant chemotherapy and resection of esophagogastric cancer was the only independent predictor of survival.

Lymph node status after undergoing neoadjuvant chemotherapy and resection of esophagogastric cancer was the only independent predictor of survival among patients in the MAGIC trial.

“Our results validate the results of the largest previous uncontrolled series, which also reported that lymph node status is more important as a prognostic variable than tumor regression,” wrote Elizabeth C. Smyth, MB, of Royal Marsden Hospital, and colleagues in the Journal of Clinical Oncology. “This finding underscores the paramount importance of adequate lymph node resection for accurate staging and, hence, prognosis prediction in patients with gastroesophageal cancer.”

Previous results from the MAGIC trial compared perioperative chemotherapy plus surgery with surgery alone, and established perioperative epirubicin, cisplatin, fluorouracil chemotherapy as the standard of care for patients with resectable esophagogastric cancer. With this study, Smyth and colleagues wanted to explore if pathologic response and lymph node status after neoadjuvant chemotherapy would predict which patients were more likely to relapse.

They evaluated 330 resection specimens taken from patients and found a survival advantage for patients with lower tumor regression grading (TRG) status. In those patients in MAGIC treated with chemotherapy who had a TRG of 1 or 2, the median overall survival was not reached; however, patients with a TRG of 3, 4, or 5 had a median overall survival of 20.47 months.

The univariate analysis of the data showed that both high TRG and lymph node metastases were negatively related to survival (hazard ratio [HR], 1.94 [95% CI, 1.11–3.39]; P = .0209). However, multivariate analysis showed that lymph node status was the only independent predictor of overall survival (HR, 3.36 [95% CI, 1.70–6.63]; P < .001).

Median overall survival in patients with node-negative disease, whether they were responders (Group A) or nonresponders (Group B), was not reached “because it was greater than the longest censoring time.” In contrast, the median overall survival for node-positive responders (Group C) was 17.3 months, and 15.5 months for node-positive nonresponders (Group D). The 5-year overall survival rates for these groups were 66%, 50%, 71.8%, and 16.2%, respectively.

“It is also important to note that even the patients with a poor pathologic response have a chance of cure (28.9% 5-year survival in our model). Thus, even a modest response to chemotherapy may play an important role in survival outcomes, and TRG may not be sensitive to these changes,” the researchers wrote. “The only firm conclusion that can currently be made is that node-positive nonresponders are a relatively poor prognosis group, and only a future randomized trial can accurately determine whether changing or intensifying treatment of nonresponders will result in improvements in overall survival for these patients.”