Metachronous, colitis-associated rectal cancer that developed after sporadic adenocarcinoma in an adenoma in a patient with longstanding Crohn's disease: a case report.
BACKGROUND
Colorectal cancer associated with Crohn's disease (CD) is increasing in proportion to the number of patients with CD in Japan. There are two subtypes of colorectal cancer with CD: sporadic cancer and colitis-associated cancer. Early diagnosis of colitis-associated cancer is sometimes difficult; when colorectal cancer is found in patients with CD, both colitis-associated cancer and sporadic cancer should be kept in mind. Here, we describe a case of metachronous, colitis-associated rectal cancer that developed after the complete resection of an adenoma that became a sporadic adenocarcinoma in a patient with longstanding CD. To the best of our knowledge, this is the first report of colitis-associated cancer in a patient with CD after removal of a sporadic cancer.


METHODS
We describe a 51-year old man with CD who had difficulty in defecation. A rectal polyp was detected and a transanal resection of the polyp was performed. A histopathological examination showed an adenoma with sporadic adenocarcinoma. After three years, a follow-up colonoscopy revealed a reddish, elevated lesion in the patient's rectum. A colonoscopic biopsy showed a signet ring cell carcinoma. We performed an abdominoperineal resection of the rectum and a bilateral pelvic lymph node dissection. A histopathological examination revealed a mucinous adenocarcinoma with signet ring cell carcinoma and lymph node metastasis. The patient received adjuvant chemotherapy with oral uracil 224 mg combined with tegafur 100 mg plus leucovorin. No signs of recurrence were noted at a follow-up 18 months after the third surgery and 60 months after the second surgery.
Department of Surgery, Gastroenterological Surgery, Graduate School of Medicine, Osaka University, 2-2 Yamada-Oka, Suita, Osaka 565-0871, Japan. tmizushima@gesurg.med.osaka-u.ac.jp.
Hiroshi
H
Takeyama
Tsunekazu
T
Mizushima
Kiyokazu
K
Nakajima
Mamoru
M
Uemura
Naotsugu
N
Haraguchi
Junichi
J
Nishimura
Taishi
T
Hata
Ichiro
I
Takemasa
Hirofumi
H
Yamamoto
Yuichiro
Y
Doki
Masaki
M
Mori
D002288:Adenocarcinoma, Mucinous / Q000556:secondary* / Q000628:therapy; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D018279:Carcinoma, Signet Ring Cell / Q000175:diagnosis / Q000556:secondary* / Q000628:therapy; D003131:Combined Modality Therapy; D003424:Crohn Disease / Q000150:complications*; D006801:Humans; D002955:Leucovorin / Q000008:administration & dosage; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D016609:Neoplasms, Second Primary; D011379:Prognosis; D012004:Rectal Neoplasms / Q000473:pathology* / Q000628:therapy; D005641:Tegafur / Q000008:administration & dosage; D014498:Uracil / Q000008:administration & dosage
D005641:Tegafur; D014498:Uracil; D002955:Leucovorin