A Clinical Suspicion That Led to the Diagnosis of May-Thurner Syndrome

May-Thurner syndrome is an anatomical anomaly characterized by venous compression of the iliac vein by the arterial system. It is more common in women. It may be asymptomatic or lead to symptoms related to hypertension/venous occlusion, namely, edema of the lower limb. The exact value of its prevalence is unknown. This case reports a 52-year-old woman with a personal history of cervical cancer. She went to her family doctor in June 2021 with complaints of edema of the left thigh, evolving over one week, without associated trauma or pain. She was directed to the emergency service, where after carrying out blood analysis, an indication for topical anti-inflammatories and monitoring of alarm signs was given. She went to the emergency service two more times in the next month with the same indications for treatment. In September 2022, during a family doctor's appointment, she again mentioned concerns regarding asymmetry of her legs. On objective examination, varicose veins were observed bilaterally. Blood analysis and arterial and venous echo-Doppler were required. There were no changes in the blood analysis. The echo-Doppler was not very conclusive, showing only slightly insufficient perforating veins. It was decided to request an abdominopelvic computed tomography (CT) whose result in February 2023 demonstrated extrinsic compression at the emergence of the left common iliac vein by the right iliac artery, likely related to May-Thurner syndrome. This clinical case recalls the importance of the family doctor in the longitudinal monitoring of his patients. The unique opportunity to learn about their background and evaluate them when surveying diagnostic hypotheses led to an unexpected diagnosis.