Colon Cancer and a Separate Liposarcoma Recurring at the Same Time

What happened, in summary

A 62-year-old man had a sigmoid-colon mass found during screening colonoscopy. Biopsy showed adenocarcinoma, and staging CT found no other disease. He underwent sigmoid colon resection with negative margins. Pathology showed poorly differentiated pT3N2a colon cancer. A small mesenteric mass removed during the same operation proved to be a separate dedifferentiated liposarcoma rather than spread from the colon cancer.

Because the colon cancer involved lymph nodes, he received adjuvant FOLFOX chemotherapy. More than 2 years of surveillance CT scans showed no disease. Almost 2.5 years after surgery, the colon cancer recurred at the same time as the separate liposarcoma. A 2 cm liver lesion and an enlarged pelvic lymph node were confirmed as metastatic colon adenocarcinoma.

He began FOLFIRI for the recurrent colon cancer, which took priority because it was metastatic. Follow-up PET imaging showed a complete response in the liver and pelvic lymph node. The liposarcoma remained a separate disease and was later removed surgically. At publication, he was 4.2 years from the first operation and 1.7 years from recurrence, with no evidence of disease on follow-up CT.