Aims
The purpose of this study is to investigate predictors of metastasis in patients with pheochromocytoma or paraganglioma (PPGLs). Predictors consist of clinical, biochemical, genetic, and pathoanatomical characteristics.
Methods
This is single center retrospective cohort study with PPGLs patients in Samsung medical center from January 2013 to January 2023. Patients who have synchronous metastasis at initial diagnosis were excluded. Also head and neck PPGLs patients were excluded too. Total 232 patients were included.
All patients received genetic screening with SDHB mutation. And ages at initial diagnosis, sex, body mass index at initial diagnosis, secretory type, tumor location, largest tumor sizes, PASS score (pheochromocytoma of the adrenal gland scaled score), ASES score (age, size, extra-adrenal, secretory type), AJCC staging were extracted. Cox regression hazard model was used to analyze associations between metastasis and genetic or epigenetic factors.
Results
A total of 13 patients metastasized during the follow-up period. They showed larger tumor size (>6cm), higher PASS score (≥4), higher ASES score (≥2), Advanced stage in AJCC staging, more SDHB mutation at baseline compared to non-metastatic patients. Especially none of the patients who were in the first stage of AJCC staging had metastasis. And none of the patients who had lower PASS score (<4) had metastasis.
In cox regression hazard model, larger tumor size (≥6cm) was significantly associated with metastasis (HR : 13.7, P=0.017). On ROC analysis, the AUC of the tumor size was 0.7829 for metastasis. Furthermore SDHB mutation was significantly associated with metastasis (HR:16.3, P=0.023). On ROC analysis, the AUC of SDHB mutation was 0.6040
But ASES score (≥2) was not associated metastasis. (HR:1.91, P=0.475).
Conclusion
Larger tumor size at initial diagnosis is independent predictors of metastatic behavior of patients with PPGLs.