唐司 則之, 小野田 昌一, 磯野 可一

Noriyuki TOHNOSU, Shoichi ONODA, Kaichi ISONO

千葉大学医学部第二外科

Second Department of Surgery, School of Medicine, Chiba University

キーワード : Ultrasonography, Esophageal cancer, Cervical lymph node metastasis, Ratio of shortest and longest diameters (S/L)

Cervical lymph node metastasis was evaluated ultrasonographically in 54 esophageal cancer patients operated in our institute from April 1985 to February 1987. Ratio of shortest and largest diameters (S/L) exceeding 0.5 in the lymph node over 10 mm in size suggested metastasis in the analysis of the 1071 removed and 146 detected lymph nodes.
In order to investigate the relationship between S/L and cancer occupying rate, the microscopic specimens of the 68 metastatic lymph nodes were magnified eight or sixteen times using a magnifying apparatus to be traced on a sheet of paper. Then, the total number of areas in each of the cancer lesion and the lymph node cut surface was measured with the aid of a microcomputer, cancer occupying rate being given by dividing the former by the latter.
In the lymph nodes of 5-9 mm in size, the average of cancer occupying rate was only 29.6% and 30.5% respectively in the S/L under 0.5 and S/L over 0.5 groups. On the other hand, in the lymph nodes over 10 mm in size, the average of cancer occupying rate demonstrated 58.5%, 70.7% and 62.5%, respectively in 10-14 mm, 15-19 mm and 20mm- divisions.
Thus, it was revealed that cancer proliferation in the metastatic lymph nodes had close relationship with increased ratio of shortest and longest diameters.
According to the ultrasonographic analysis of the 16 removed lymph nodes, one scanning direction (sagittal or transverse) will be enough to measure S/L for diagnosing metastasis.