| Theme | Early Esophageal cancer-from the Viewpoint of its Type and the Depth of Invasion | |
|---|---|---|
| Title | Pathology of Early Esophageal Cancer: Relationship between Superficial Cancer and Lymph Node Metastatis | |
| Publish Date | 1997/11 | |
| Author | Hisanobu Tomimatsu | Department of Pathology, Cancer Institute |
| Author | Akio Yagisawa | Department of Pathology, Cancer Institute |
| [ Summary ] | The relationship between lymph node metastasis and various pathological factors was studied in 33 patients(33 lesions) with untreated mucosal cancer of the esophagus and 91 patients(91 lesions) with submucosal cancer of the esophagus who underwent resection at the Department of Surgery of the Cancer Institute. (1) With cancer of up to m2 in depth, no vascular invasion or lymph node metastasis was found (0/22). At a depth of m3, however, both lymphatic invasion and lymph node metastasis occurred at frequencies of 36.4% and 18.2%, respectively. From these findings, it appears that early cancer for which long-term survival can be expected should not exceed a depth of m2. Clinically, the absolute indication for endoscopic resection is a depth of invasion not exceeding m2. (2) When sm1 invasion was defined as microinvasive cancer with the distance from the muscularis mucosae to the deepest part of the cancer being under 200microm, the lymphatic invasion rate was 66.7% and the lymph node metastasis rate was 23.5%, both being high. Accordingly, the lymph node metastasis rate of sm1 cancer, as classified according to the conventional classification of submucosal (sm) invasion into three stages (sm1-3), is high based on these results. (3) The features associated with a strong possibility of lymph node metastasis at invasion depths of m3, to sm1 are destruction of the basement membrane by the cancer and the presence of Droplet infiltration (DI) in the lamina propria. The lymph node metastasis rate in m3 or sm1 DI-positive patients was 36.8% (7/19). None of the DI-negative patients had lymph node metastasis (0/7). It is interesting that lymph node metastasis was seen in two patients without lymphatio invasion who were DI-positive, indicating that DI is an important histological finding for assessment of lymph node metastasis. (4) A study of macroscopic features related to the absence of lymph node metastasis showed that it was already present in the 0-IIb, 0-IIa basic and IIa mixed types at heights of 0.3 mm or more and there was no clear relationship between height and lymph node metastasis. In type 0-IIc, five conditions had to be met : a flat depressed surface, an didistinct boundary of the depression, no peripheral protrusion, a depression not more than 0.2 mm deep, and a light brown color. |
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