A case of asymptomatic right-sided adult Bochdalek hernia presented incidentally with rectal tumor

　We encountered a patient with an adult Bochdalek hernia discovered asymptomatically. A 77-year-old Japanese woman visited a local clinic with chief complaints of melena and difficulty in defecation. Based on the results of the detailed examination in our hospital, she was diagnosed with a rectal gastrointestinal stromal tumor (GIST) with a concurrent asymptomatic adult right-sided Bochdalek hernia. Because the tumor was large, laparoscopic abdominoperineal rectal amputation was performed after systemic imatinib therapy. During the surgery, we found a right diaphragmatic defect more than 13cm in long dia., through which the right hepatic lobe, colon, and greater omentum had prolapsed into the right thoracic cavity. No visceral adhesions were noted. No hernia sac was observed. Adult Bochdalek hernia is a relatively rare condition, and only three (incidentally discovered) cases of asymptomatic Bochdalek hernia, including the present case, have been reported in Japan. Here we provide a case report for the patient, who was followed-up without hernia surgery, plus a review of the literature.

症例報告 (Case Reports)