M. Shinozaki*1, R. Takahashi1
1The University of Tokyo, Surgery, Tokyo, Japan
Patients with Crohn’s disease (CD) have increased risk of developing intestinal cancer (IC). However, the factors to determine the prognosis of such cancer have not been revealed yet. The aim of this study was to clarify the factors to determine prognosis of IC in CD.
We searched for IC cases associated with CD from a Japanese medical database (Ichushi) between 1983 and 2015, using two keywords (Crohn’s disease and malignancy), picking up only IC, and arranging duplicates. The total number of cases were 271, and the prognosis was described in 141. The patients were classified to two groups: Survival group (n = 51; observation time = 16 (3–132) months (median (range)) and Death-Recurrence (DR) group (n = 93: observation time = 10 (0.6–72) months), where the latter includes patients with advanced disease, residual cancer after surgical treatment. or recurrence after curatively intended operation.
The age at IC diagnosis is younger in DR group (39.5 (25–84) vs. 46 (27–73); p < 0.01). The age at Crohn’s disease was also younger in DR group (27 (14–69) vs. 24 (6–69); p < 0.05), and the durations of each group were similar (15 years vs. 16.5). Penetrating disease behaviour was more frequent in DR group (60% vs. 39%), but the difference did not reach statistical significance (p = 0.08). The proportion of fistula-originated cancer was similar (48% vs. 16%; p < 0.01). In DR group, the cancer was located more frequently around the rectum (rectum and anus; 68% vs. 51%; p < 0.05). Preoperative diagnosis was achieved less frequently in DR group (58% vs. 67%) without statistical significance. The histology of cancer was 10%:19%:11%:7%:49% (well differentiated: moderately differentiated: poorly differentiated: signet ring cell: mucinous) in DR group and 52%:14%:2%:0%:26% in Survival group, and the proportion of well differentiated adenocarcinoma was significantly lower in the former (p < 0.01). IC stage at diagnosis was 1%:3%:23%:35%:38% (stage 0:1:2:3:4) in DR group and 10%:30%:50%:10%:0% in Survival group, and the proportion of Stage 3 was higher in the latter (p < 0.01).
In conclusion, young IC and CD diagnosis, fistula-originated cancer, cancer around rectum, Stage 3 or more advancer, and histology other than well differentiated carcinoma were risk factors for poorer prognosis in IC associated with CD.