How [18F]-FDG-PET/CT Affects Clinical Management of Patients with Germ Cell Tumors in the Real World

SIMPLE SUMMARY: This study aimed to assess the impact of PET/CT on the management of patients with germ cell tumors (GCTs) in a real-world setting, specifically in terms of avoiding invasive procedures, reducing additional diagnostic imaging, and influencing treatment decisions. A total of 43 male GCT patients were included in this study, and their intended management before and after PET/CT was documented. The results showed that PET/CT caused changes in oncologic staging in 51% of patients, with 16% of patients upstaged, 23% of patients downstaged, and 11% of patients experiencing cancer relapse. Although the number of patients receiving curative treatment remained stable, there were notable changes in the intended therapeutic interventions. Planned chemotherapy increased from three to eleven patients, while planned surgical resection decreased from eleven to two patients. Moreover, PET/CT helped to avoid invasive procedures in 19% of cases and to reduce the need for additional diagnostic procedures in 58% of cases. In conclusion, the use of PET/CT had a significant impact on the clinical stage, resulting in a reduction in invasive and diagnostic procedures. These findings are expected to have even greater significance in the future as treatment options improve and GCT patient survival rates increase. ABSTRACT: Objective: The aim of this study was to evaluate the impact of PET/CT on clinical management of patients with germ cell tumors (GCTs) conducted in a real-world setting, including avoidance of invasive procedures, additional diagnostic imaging, and changes in treatment. Methods: Patients with GCTs were prospectively enrolled into a PET/CT registry study between May 2013 and April 2021. Intended patient management prior and after PET/CT was documented using standardized questionnaires. Changes in oncologic staging and clinical management after PET/CT were recorded, including planned treatment and planned additional diagnostics. Results: Forty-three male patients with GCTs were included consecutively in this study. After PET/CT, oncologic staging changed in 22/43 patients (51%), with upstaging in seven cases (16%), downstaging in ten cases (23%), and cancer relapse in five cases (11%). The number of patients with intended curative treatment remained stable, while a considerable change in intended therapeutic intervention was noted after PET/CT, with an increase in planned chemotherapy from three to eleven patients and a decrease in planned surgical resection from eleven to two patients. In addition, PET/CT contributed to preventing patients from intended invasive procedures including biopsy and surgery in 8/43 (19%) cases and from additional diagnostic procedures in 25 (58%) cases. Conclusion: With the use of FDG-PET/CT as a tool to guide patient management in GCTs, we observed a notable impact on clinical staging and a consequent reduction in the need for additional invasive and diagnostic procedures. These findings are expected to be even more consequential in the future as treatment modalities improve and the life expectancy of GCT patients further increases. Key Points: PET/CT considerably influences the clinical stage of GCT patients. PET/CT has remarkable influence on the choice of therapeutic interventions and reduces additional diagnostic procedures.