十二指腸乳頭部早期癌の考え方

Concept on Early Cancer of the Ampulla of Vater

要旨　十二指腸乳頭部癌切除例67例を対象として，特に組織学的に十二指腸浸潤のないd₀の症例を中心に検討した．d₀を癌浸潤が粘膜内にとどまるd₀αと癌浸潤がOddi筋に達するd₀βに分けて検討したところ，d₀αではいずれもly（－），v（－），n（－）で，全例生存しており，またd₀βになるとvは全例陰性で，ly（＋）40％，n（＋）20％であったが，予後は良好で，再発死亡例はなかった．更に癌浸潤がOddi筋を越えて浸潤（d₁以上）すると，脈管侵襲やリンパ節転移が高率となり，膵浸潤も認められるようになり，再発死亡例もあり，遠隔成績は不良となった．したがって，現時点では十二指腸乳頭部早期癌とはリンパ節転移の有無を問わず“組織学的に癌浸潤がOddi筋内にとどまるもの”とするのが妥当と考えている．

　In order to better define early cancer of the ampulla of Vater, 67 cases in which the cancer of the ampulla of Vater was resected in our department were microscopically examined regarding, in particular, invasion of carcinoma within the muscle of Oddi (d₀) . Patients with carcinoma of d₀ were classified according to the following criteria: d₀α is carcinoma restricted within the mucosa and d₀β is carcinoma with invasion into but not beyond the muscle of Oddi.

　In case of d₀α, neither lymphatic nor venous invasion was evident and no cancer death occurred after surgery. In case of d₀β, although venous invasion was not found, lymphatic permeation was seen in 40％ and lymph node metastasis in 20％. Prognosis, however, was favorable for this group; no recurrence of carcinoma after surgery. Furthermore, in cases with carcinoma extending beyond the boundary of the muscle of Oddi, prognosis was unfavorable, i.e., high rates of lymphatic permeation, venous invasion, perineural invasion and lymph node metastasis as well as high rate of recurrence after surgery.

　At present, therefore, early carcinoma of the ampulla of Vater may well be defined as carcinoma restricted within the muscle of Oddi.