Incidence of pheochromocytoma and sympathetic paraganglioma in the Netherlands: A nationwide study and systematic review

Introduction: Recent years have seen major changes in clinical practice which may have affected the incidence rates of pheochromocytoma(PCC)/sympathetic paraganglioma(sPGL). There is, however, a lack of up-to-date information describing trends in these incidence rates.
Methods: We searched the Dutch pathology registry to identify all histopathologically confirmed cases of PCC/sPGL diagnosed between 1995 and 2015. We calculated incidence rates according to age category as well as age-standardized incidence rates (ASR). We also searched Medline and Embase to find data on nationwide incidence rates of PCC/sPGL.
Results: The nationwide pathology study revealed a total of 1493 patients with either PCC or sPGL. The ASR for PCC increased from 0.29 (95% CI: 0.24-0.33) to 0.46 (95% CI: 0.39-0.53) per 100,000 person-years in the periods 1995-1999 and 2011-2015, respectively. For sPGL the ASR in these same periods were 0.08 (95% CI: 0.06-0.10) and 0.11 (95% CI: 0.09-0.13) per 100,000 person-years, respectively. Concomitantly, PCC size decreased (β -0.17; P < .001) and age at diagnosis increased (β 0.13; P = .001). Our systematic search yielded 3 papers reporting on a total of 530 PCC/sPGL cases, showing a combined annual incidence rate varying from 0.04 to 0.21 per 100,000 person-years.
Conclusion: Incidence rates of PCC/sPGL have increased significantly over the past two decades. This trend coincides with a higher age and a smaller tumor size at diagnosis. Most likely these observations are at least in part the result of changes in clinical practice during the study period, with a more intensified use of both imaging studies and biochemical tests for detecting PCC/sPGL.