Gotoda classification

논문 작업에 필요해서 적어둠.(1)

1. Gotoda absolute indication
   1. differentiated-type
   2. without ulceration
   3. clinically T1a
   4. <= 2cm
2. Gotoda expanded classification
   1. differentiated, no ulceration, >2cm
   2. differentiated, ulceration, <=3cm
   3. undifferentiated, no ulceration, <=2cm