Background/aims: Primary achalasia is a premalignant disorder of the esophagus. The studies for esophageal cancer pathogenesis may reveal early diagnosis of esophageal cancer. DNA aneuploidy, p53 mutations and cellular proliferation are important factors in cancer development. As far as we know, we have not encountered any study on these factors in achalasia.
Methodology: We studied DNA ploidy by flow cytometry and p53 and PCNA index by immunohistochemical technique and studied histopathology in the esophageal mucosa of primary achalasia and control patients.
Results: DNA analysis revealed aneuploidy in 2 of 20 achalasia patients but none of the 18 control patients. Sixty-five percent of achalasia and 22% of normal patients showed p53 positivity (P < 0.05). We have found normal mucosa, basal cell hyperplasia-esophagitis and dysplasia in 13, 22 and 3 patients and p53 positivity in 2, 12 and 3 of these patients, respectively (P < 0.05). PCNA labeling indexes (as % +/- SD) were 34.8 +/- 12.2, and 28.4 +/- 9.3 in achalasia and control groups, respectively (P > 0.05). PCNA labeling index was 28.0 +/- 8.2 in p53(-) and 36.0 +/- 12.9 in p53(+) patients (P < 0.05). PCNA indexes were found 29.3 +/- 9.6 in normal histopathologic group, 31.8 +/- 13.4 in basal cell hyperplasia-esophagitis, and 41.7 +/- 6.5 in dysplasia group (P > 0.05).
Conclusions: DNA aneuploidy, p53 positivity, and higher cellular proliferation index may have important role in the pathogenesis of esophageal cancer in primary achalasia.