[A case of locally advanced rectal cancer successfully treated by laparoscopic intersphincteric resection and effective neoadjuvant chemoradiation therapy].

ABSTRACT

A 74-year-old woman was diagnosed as having lower rectal cancer. Colonoscopy revealed a type 2 circular tumor over 15 cm from the port side close to the dentate line. The patient was diagnosed as having a moderately differentiated adenocarcinoma by biopsy. Computed tomography (CT) and fluorodeoxyglucose (FDG)-positron emission tomography (PET) revealed thickening of the wall from near the anus to the rectosigmoid junction and an increase in the concentration of the surrounding adipose tissue as well as swelling of the left internal iliac lymph nodes with FDG accumulation. The patient was diagnosed as having cSE, cN3, cM0, cStage IIIb rectal cancer. Because the tumor was very close to the anus with advanced extramural invasion and because the patient desired anal sphincter preservation, we performed preoperative chemoradiation therapy( CRT) combined with capecitabine plus oxaliplatin( XELOX) and bevacizumab( BV). Radiation therapy was performed with a linear accelerator( LINAC) for stereotactic radiation therapy( Novalis®). Partial response (PR) was achieved by this therapy. Five weeks after CRT, the patient underwent laparoscopic-assisted intersphincteric resection( total ISR). Pathological examination revealed minimal residual cancer cells( Grade 2, pPR, pA, N0, M0, pPM0, pDM0, pRM0, pStage II). Increased implementation of anus-preserving surgery can be expected owing to the successful control of regional and distant metastases by neoadjuvant CRT. Based on these encouraging findings, we should consider the challenges posed by neoadjuvant CRT for the treatment of lower rectal cancer.