[A Case of Locally Advanced Appendiceal Cancer with Radical Resection after CAPOX plus Bevacizumab].

We report a case of a male in his sixties with appendiceal cancer who underwent radical resection following CAPOX plus bevacizumab neoadjuvant chemotherapy. The patient presented to our hospital with a chief complaint of chronic low abdominal pain. Contrast-enhanced CT before neoadjuvant chemotherapy revealed an inhomogeneous tumor in the ileocecal region. Invasion to the bladder and the sigmoid colon was also observed. A colonoscopy showed an elevated lesion, which was caused by extramural invasion to the sigmoid colon. Pathological examination of the sigmoid colon tumor revealed well differentiated tubular adenocarcinoma and KRAS codon13 G13D. Hence, we diagnosed the patient with locally advanced appendiceal cancer with invasion to the bladder and sigmoid colon. We administered CAPOX plus bevacizumab as neoadjuvant chemotherapy. Contrast-enhanced abdominal CT after neoadjuvant chemotherapy revealed shrinkage of the primary tumor and reduction in the invasion to the bladder and sigmoid colon. We performed ileocecal resection(+D3), a partial sigmoidectomy, and partial bladder resection on the 135th day from the diagnosis. The resected specimen showed an appendiceal tumor with invasion to the bladder and sigmoid colon. The pathological diagnosis was Ⅴ, yType 5, tub2>tub1, ypT4b, ypN0, ycH0, ycM0, ycPUL0, Ly1b, V1b(VB), Pn01b, pStage Ⅱa, and the histological treatment effect of preoperative therapy was Grade 1b. Our experience indicates that in patients with locally advanced appendiceal cancer, multimodal treatment with neoadjuvant chemotherapy is an effective option.