Ultrasonographic evaluation of cervical lymph node metastases in esophageal cancer with special reference to the relationship between the short to long axis ratio (S/L) and the cancer content.

Cervical lymph node metastasis was evaluated sonographically in 58 esophageal cancer patients. The short to long axis ratio (S/L) is a useful way to detect lymph node metastasis as opposed to the long axis alone. In other words, the lymph node exceeding 10 mm in long axis and with S/L over 0.5 showed a much higher incidence of metastasis than S/L under 0.5 in the analysis of the 126 detected lymph nodes. The cancer content was calculated with a microcomputer in each of the total 77 metastatic lymph nodes by enlarging the microscopic specimen 8 or 16 times using a magnifying apparatus. The average cancer content in the metastatic lymph nodes with S/L under 0.5 and over 0.5 was 26.0% and 59.1%, respectively, revealing a statistically significant difference (p less than 0.01). Thus, cancer proliferation in the metastatic lymph nodes of esophageal cancer is closely related to the increase in S/L.