Non-occlusive mesenteric ischaemia (NOMI) refers to irreversible intestinal ischaemia and necrosis in the absence of organic obstruction to the mesenteric blood vessels. In cases of delayed diagnosis, the prognosis is poor and the mortality rate is 58-70%, being the highest among patients with acute mesenteric ischaemia. The risk factors for this disease include heart disease, sepsis, and administration of catecholamines and digitalis; however, there are few reports of its onset during drug therapy for malignant tumours. The present study reported the case of an 85-year-old man who developed NOMI during drug therapy for maxillary cancer. The patient was diagnosed with right maxillary carcinoma, for which paclitaxel, carboplatin and cetuximab (PCE) therapy was administered. Four days after starting the second course of PCE therapy, the patient visited the emergency department of our hospital with chief complaints of melena and abdominal pain. Contrast-enhanced computed tomography revealed ischaemia from the transverse to the descending colon, leading to a diagnosis of NOMI. Colectomy and colostomy were performed during the emergency surgery on the same day. Although the patient's general condition improved, he was transferred to a recuperation facility for palliative care.

Nonocclusive mesenteric ischemia (NOMI) causes mesenteric ischemia and intestinal necrosis despite the absence of organic obstruction, such as thrombi and emboli in mesenteric blood vessels, and it has an extremely poor prognosis. We report a case of NOMI developed during bioradiotherapy (BRT) with cetuximab for cervical lymph node metastasis of tongue cancer. The patient was a 73-year-old man who underwent right radical neck dissection for neck lymph node metastasis after tongue cancer surgery. Postoperatively, the patient received BRT with cetuximab. On the 34th day after BRT, the patient had abdominal distension and a decreased level of consciousness. Contrast-enhanced computed tomography revealed mesenteric ischemia without thrombi and extensive intestinal emphysema. The patient was diagnosed with NOMI. Furthermore, he had septic shock and was treated with vasopressors and antibacterial agents; however, the condition of the patient did not improve, and he died on the same day.

Gastrointestinal complications are common in patients undergoing various forms of cancer treatments, including chemotherapy, radiation therapy, and molecular-targeted therapies. Surgical complications of oncologic therapies can occur in the upper gastrointestinal tract, small bowel, colon, and rectum. The mechanisms of action of these therapies are different. Chemotherapy includes cytotoxic drugs, which block the activity of cancer cells by targeting intracellular DNA, RNA, or proteins. Gastrointestinal symptoms are very common during chemotherapy, due to a direct effect on the intestinal mucosa resulting in edema, inflammation, ulceration, and stricture. Serious adverse events have been described as complications of molecular targeted therapies, including bowel perforation, bleeding, and pneumatosis intestinalis, which may require surgical evaluation. Radiotherapy is a local anti-cancer therapy, which uses ionizing radiation to cause inhibition of cell division and ultimately lead to cell death. Complications related to radiotherapy can be both acute and chronic. Ablative therapies, including radiofrequency, laser, microwave, cryoablation, and chemical ablation with acetic acid or ethanol, can cause thermal or chemical injuries to the nearby structures. Treatment of the different gastrointestinal complications should be tailored to the individual patient and based on the underlying pathophysiology of the complication. Furthermore, it is important to know the stage and prognosis of the disease, and a multidisciplinary approach is necessary to personalize the surgical treatment. The purpose of this narrative review is to describe complications related to different oncologic therapies that may require surgical interventions.