Does protruding type 1 esophageal cancer really have a good response to radiation therapy?-a retrospective observational study.

BACKGROUND

It is now well-established that esophageal cancer can be more accurately classified macroscopically on the basis of endoscopic rather than esophagographic findings. Thus far, no studies have reported correlations between responses to radiation therapy (RT) and endoscopically-determined macroscopic type of locally advanced esophageal cancer. In this retrospective study, we therefore aimed to determine such correlations in patients who had undergone at least two follow-up endoscopies.

METHODS

Our study cohort comprised 30 patients who had received radiotherapy for locally advanced squamous cell carcinoma (SCC) of the esophagus from January 2012 to November 2017 at our hospital. The lesions had been classified endoscopically into one of the five types specified by the Guidelines for Clinical and Pathologic Studies on Carcinoma of the Esophagus of the Japanese Society for Esophageal Disease. All patients had received radiotherapy and 27 had received chemotherapy. In accordance with those guidelines, responses to treatment were evaluated endoscopically, a median of 74 days after initiating radiotherapy. Follow-up endoscopy had been performed at least twice in 18/30 patients.

RESULTS

The primary complete response (CR) rate was significantly higher in patients with type 1 disease (protruding) than in those with the other types (χ test, P=0.041). The only correlation revealed by logistic regression analysis was between CR rate and macroscopically classified type 1 disease (P=0.05). Disease-specific survival (DSS) did not differ between macroscopically classified types (P=0.31). Patients with clinical T2 disease and ≤ stage IIIA had better outcomes than those with other stages (P=0.041 and 0.025, respectively).

CONCLUSIONS

Macroscopic classification of esophageal carcinoma by endoscopy accurately identifies a group with a higher primary CR rate to chemoradiotherapy (CRT): those with type 1 disease (protruding). However, median DSS did not differ between patients with type 1 disease and those with other types.