Spontaneous internal jugular vein thrombosis: primary manifestation of a colorectal adenocarcinoma in a very old woman.

We report the history of a very old woman with a spontaneous internal jugular vein thrombosis as the presenting feature of an occult adenocarcinoma of the caecum. Spontaneous internal jugular vein thrombosis is an unusual form of venous thrombosis. Doppler ultrasound and Computed Tomography or Magnetic Resonance Imaging should confirm signs and symptoms suggesting thrombosis. Immediate anticoagulation with heparin followed by oral anticoagulation is mandatory to reduce associated mortality and morbidity. If no risk factors for internal jugular vein thrombosis are present, a work-up for hypercoagulable states and a careful search for distant malignancy should been obtained. If screening shows no obvious malignancy, further follow-up is necessary.