To be or not to be: A two years surveillance for a CA 19-9 persistent elevation before cancer diagnosis and bone metastases

Background. CA 19-9 is an antigen expressed by several epithelial cells and currently used for the diagnosis and follow-up of gastrointestinal cancers. Even if a serum level > 1000 UI/ml has a specificity for pancreatic cancer of 99.8% its elevation is also reported in benign diseases. The pancreatic ductal adenocarcinoma is tipically aggressive and therefore shorter follow-up are expected to be found before diagnosis. Case presentation. A 75-years-old female referred to us for evaluation of high level of serum CA 19-9 (558 UI/ ml) observed for the first time one year before when she had also been undergone colonoscopy that have excluded neoplasms. At the adimission she complained fatigue, weight loss, hyporexia, nausea, low-grade fever and intermittent self-limiting skin lesions of the lower limbs. Serum CA 19-9 level was > 1000 UI/ml. Her past medical history was significant for chronic HCV hepatitis, essential hypertension and hysterectomy for leiomyofibroma of the uterus thirty years before. We did not found any neoplasm and scheduled a close follow-up with colonoscopy, CT and PET for one additional year. At the end of December 2015 we observed the appearance of small painful nodules in the subcutaneous periumbilical region and a CT showed a pancreatic tail malignancy and bone metastases. Periumbilical biopsy was performed and the diagnosis of pancreatic ductal adenocarcinoma was proven. Conclusion. A long time observation of a persistent and progressive CA 19-9 increase should never exclude the malignant origin. The trend, more than the duration of this finding may guide clinical decision.