ID #184 Outcomes of children with germinoma treated without primary tumor boost: experience from a university hospital in Malaysia.

Background

Response-adapted radiation therapy has been the treatment approach for germinoma after neoadjuvant chemotherapy. However, the presence of residual lesions at the end of chemotherapy did not demonstrate a negative impact on progression-free survival (PFS). While no malignant component was found generally in excised residuals, resection of residual tumors after chemotherapy did not also demonstrate a survival benefit.

Aim

To determine outcomes of germinoma patients who received chemotherapy and radiation therapy without primary tumor boost.

Method

This is a retrospective study analyzing the outcome of a cohort of paediatric germinoma patients treated with 4 cycles of carboplatin/ etoposide chemotherapy followed by cranial radiotherapy without primary tumor boost in a university hospital in Malaysia from January 2023 to December 2024.

Result

5 patients (5 male; mean age 14.3years) were analysed. Median follow-up was 25months (range 17-26months). Four children had localized disease and tumor location was pituitary stalk (n = 1), pineal (n = 1), basal ganglia (n = 1) and bifocal (n = 1)while 1 child had intracranial metastatic disease at presentation. After chemotherapy, complete response was achieved in one patient who had pituitary stalk involvement, and 4 achieved partial response. All patients received radiotherapy to 23.4 Gy regardless of the chemotherapy response. Two patients with basal ganglia and cranial metastatic disease received whole brain irradiation . Whole ventricular irradiation was delivered to the other 3 patients. The 4 patients with partial response post-chemotherapy continued to demonstrate further reduction of tumor size after radiotherapy or during subsequent 3-monthly surveillance imaging. One patient showed a residual tumour during the last MRI. Event-free survival was 100% in this cohort.

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