Multimodal therapy comprising neoadjuvant chemotherapy and radiation therapy prior to radical resection is increasingly utilized in gastroesophageal cancer.
The achievement of a complete pathological response or a major response is associated with an improved survival.
However, up to 70% of patients show an incomplete or no response to the neoadjuvant regimen.
The identification of factors which predict a response would be of considerable clinical benefit.
Dr MacGuill and colleagues from Ireland performed a retrospective analysis of a prospectively updated esophageal cancer database.
The predictive values of several clinicopathological factors were investigated.
The team assessed age, sex, tobacco, alcohol, weight, clinical history, tumor type, site, length, width, morphology and differentiation.
| The median tumor length in the pathological response group was 2cm|
|Diseases of the Esophagus|
Statistical analysis was performed using Chi-square test with Pearson's test or Kruskal-Wallis test.
The researchers identified 176 patients who had undergone neo-adjuvant chemoradiotherapy at St James's Hospital Dublin between 1990 and 2003.
A complete pathological response was seen in 23% of patients.
The team noted a significant relationship between response to chemoradiotherapy and pretreatment tumor length.
The median tumor length in the pathological response group was 2cm compared with 3cm in non-responders.
The researchers observed that body weight, sex, tobacco or alcohol usage, tumor site, or differentiation were not predictive of response.
However, a trend was observed for squamous cell cancer compared with adenocarcinoma.
The team identified that smaller tumor length was predictive of a greater response to chemotherapy and radiation therapy.
Dr MacGuill's team concluded, “Our findings may reflect different tumor biology, perhaps with acquired resistance to treatment-induced apoptosis in the larger tumors.”
“A simpler explanation is that the existing dose and treatment schedule for combination chemoradiotherapy is suboptimal in patients with larger tumors.”