Suspicious T1 colon cancer with synchronous liver metastasis not detected by preoperative imaging study

Colorectal carcinoma invading the submucosa but not the muscularis propria (pT1) represents the earliest form of clinically relevant colorectal cancer in most patients. T1 colorectal cancer with synchronous liver metastasis is considered to be rare. We report a rare case of T1 colon cancer with synchronous liver metastasis not detected by preoperative imaging study. A 54-year-old male patient presented to our department for treatment of sigmoid colon cancer following an endoscopic submucosal dissection. Histopathological examination revealed the pedunculated mass was moderately differentiated adenocarcinoma without lymphovascular invasion and the depth of submucosal invasion was 2,000 µm, the resection margin was not involved. We performed a laparoscopic anterior resection with lymph node dissection. After the 3 months, the patient's carcinoembryonic antigen level elevated from 1.4 to 7.26 ng/mL (normal level: <1.5 ng/mL) and the abdominal computed tomography and FDG-PET/CT (positron emission tomography-computed tomography) showed multiple hepatic metastases in both hepatic lobes (SUVmax: 5.6) without evidence of local recurrence or lymphadenopathy. We strongly suspected a synchronous liver metastasis not detected by imaging study as opposed to a systemic recurrence. Therefore, evaluation and follow-up protocol of T1 colorectal cancer should be changed for discovery and prediction of synchronous liver metastasis; because we cannot exclude the possibility of synchronous liver metastasis.

The Role of the Postoperative Adjuvant Radiation Therapy to Primary Site in Rectal Cancer Patients with Synchronous Liver Metastasis / 대한치료방사선과학회지

Among the patients with rectal cancer who entered Yonsei University Hospital for management from Jan. 1980 to Dec. 1990, we selected 23 subjects who were received surgical resection of tumor in rectum, and who proved to have liver metastasis during the diagnostic work-up, at the time of the operation, or within 3 months after starting definitive treatment. With those subjects, we investigated the role of radiation therapy by comparison of the treatment results of the patients without radiation therapy (S group) with those of the patients with radiation therapy to the primary site (S+R group). The local control rates of S group and S+R group were 64% and 89%, and 2-year survival rates were 50% and 78%, respectively. Although there was not statistically meaningful difference, local control rate and 2-year survival rate were higher in the group with radiation therapy to primary site than that without radiation therapy. The 2-year survival rates of the case with resection of the liver and the case without it were 03.6% and 58.3% respectively, which was not statistically significant. Also, the 2-year survival rate of the case with sustained local control was higher than that of the case with local failure, which was statistically significant(70.5% and 16.7%, p<0.005). From the above results, it is thought that radiation therapy to the primary site might improve the local control rate even in the patients with liver metastasis, which seems to be correlated to the higher survival rate.