Extensive arterial and venous thrombosis revealing lung adenocarcinoma in a patient with managed comorbidities

We present a case of a female in her late 40s with a 5-year history of well-managed type II diabetes mellitus, systemic hypertension and dyslipidaemia presented with acute severe abdominal pain, vomiting and loose stools. Clinical assessment revealed sepsis and metabolic acidosis. Imaging demonstrated extensive arterial and venous thrombosis involving the superior mesenteric artery and vein, as well as the splenic vein. Emergency laparotomy was performed on the same day, revealing gangrenous bowel from the distal jejunum to the mid-transverse colon, necessitating resection and stoma creation. Postoperative management included anticoagulation. Given the unusual presentation of extensive thrombosis in a patient with low traditional risk factors, further investigation was pursued. Chest X-ray and High-resolution CT of the thorax revealed a right lower lobe mass with multiple pulmonary nodules and mediastinal lymphadenopathy. Biopsy confirmed primary lung adenocarcinoma (TTF-1 and CK7 positive). Subsequent positron emission tomography-CT showed widespread metastasis, and the patient was referred for palliative chemotherapy and later underwent jejunocolic anastomosis. This unique case highlights how extensive mesenteric thrombosis can be the initial manifestation of previously undiagnosed lung adenocarcinoma in a patient with otherwise well-managed comorbidities. It underscores the critical importance of considering underlying malignancy in the differential diagnosis of acute thromboembolic events to facilitate early diagnosis and potentially improve patient outcomes.