[A Case of Postoperative Recurrence of Rectal Cancer in Which Desensitization Therapy Was Effective against Oxaliplatin Allergy in L-OHP].

The case involved a 44-year-old man who underwent intersphincteric resection and lateral lymph node dissection for rectal cancer. Pathological diagnosis revealed a well-differentiated adenocarcinoma comprising KRAS wild type, and pT2N0M0 (pathological Stage I). CapeOX (capecitabine plus oxaliplatin[L-OHP]), and bevacizumab therapy was initiated because of local recurrence. Although a partial response (PR) was observed, the therapy was terminated after 6 courses because of the development of hand-foot syndrome. FOLFIRI and cetuximab therapy was initiated after cancer recurrence was observed during a follow up. As the therapeutic efficiency is characterized by stability (stable disease: SD), and the tumor reduction effect observed was not sufficient, we performed an abdominoperineal resection to achieve local control. However, a left hydronephrosis occurred due to the pelvic recurrence, necessitating the emergency hospitalization of the patient. Because resistance to L-OHP was not confirmed, mFOLFOX6 and bevacizumab therapy was introduced in hopes of the effect of the former. As Grade 2 allergy (erythema) appeared immediately after the L-OHP was administered during the 3 courses, treatment was discontinued. We the reinitiated the treatment along with the desensitization therapy from the 4 courses. A total of 27 courses of mFOLFOX6 and bevacizumab therapy were administered until the state of disease progression (progression disease: PD) was determined. PR was defined as the best therapeutic efficiency. In some cases, discontinuation of treatment is necessary as observed in the present case due to the onset of L-OHP allergies, even if the overall effect of the treatment is expected to be good. Our case is essentialas it demonstrates the successfulness of desensitization therapy for L-OHP allergies.