OBJECTIVETo detect the loss of heterozygosity (LOH) in esophageal squamous cell carcinoma and adjacent high-grade squamous dysplasia, and to evaluate possible tumor suppressor genes in the development and progression of invasive malignancy.

METHODSLOH was detected in normal esophageal mucosa, high grade squamous dysplasia and esophageal squamous cell carcinoma using microdissection and polymerase chain reaction technology. The changes of LOH at seven microsatellite markers and the relationship between LOH rate and clinicopathologic parameters were analyzed.

RESULTSIn high grade squamous dysplasia, LOH was detected at D13S802 (40%), D13S267 (32%), D13S221 (31%), D9S942 (30%), D17S520 (24%) and D9S171 (33%). However, D17S1798 LOH was not detected. In invasive squamous cell carcinoma, LOH was detected as follows: D13S267 (71%), D13S802 (58%), D17S520 (55%), D13S221 (45%), D9S942 (43%), D9S171 (33%) and D17S1798 (11%). The frequency of LOH in the seven microsatellite markers, the pathologic grade, clinical stage and occurrence of lymph node metastasis did not show any statistically significant correlation (P > 0.05).

CONCLUSIONSThe progression from normal squamous epithelium to high grade squamous dysplasia and subsequently to invasive squamous cell carcinoma of the esophagus was associated with accumulation of genetic errors. Possible tumor suppressor genes related to the development of esophageal squamous cell carcinoma may exist near D13S802 (13q12.12). Possible tumor suppressor genes near D13S267 (13q13.1), D17S1798 (17p13.3) and D17S520 (17p13.1) may be related to the progression of esophageal squamous cell carcinoma.