SEER Training Modules

Morphology & Grade

ICD-O-3 Morphology Codes

If the diagnostic term in the pathology report is not in the following list, be sure to consult your ICD-O manual.

Colon and Rectum

  • Adenocarcinoma (814_3; 98% of tumors above anal verge)
  • Mucinous (colloid) adenocarcinoma (84803)
  • Signet ring adenocarcinoma (84903)
  • Adenocarcinoma in adenomatous polyps (82103)
  • Adenocarcinoma in adenomatous polyposis coli (82203)
  • Adenocarcinoma in villous adenoma (82613)
  • Other carcinomas
  • Lymphoma (many cell types)


  • Carcinoids (82401)

Anal Cancer

  • Squamous cell carcinoma of the anus (807_ 3)
  • Cloacogenic (81243; transitional cell 81203; or basaloid 81233) carcinoma of ano-rectal junction
  • Basal cell cancer (809_3)
  • Extramammary Paget disease (85423)
  • Bowen disease (80812)
  • Malignant melanoma (872_3)
  • Sarcomas and lymphomas of the perianal soft tissues

Synonyms for in situ carcinoma: (adeno)carcinoma in an adenomatous polyp with no invasion of stalk, confined to epithelium, noninfiltrating, intraepithelial, intraepidermal (anus), involvement up to but not including the basement membrane, noninvasive, no stromal involvement, papillary noninfiltrating.