Protonterapia nel trattamento del tumore prostatico

Obiettivo: Il nostro obiettivo è stato quello di confrontare la tomoterapia (HT) e la protonterapia ad intensità modulata (IMPT) nel trattamento del tumore prostatico, seguendo un protocollo di boost simultaneo (SIB) e moderatamente ipofrazionato. Materiali e metodi: Abbiamo selezionato 8 pazienti, trattati con HT e abbiamo rielaborato i piani con 2 campi IMPT. La dose prescritta è stata di 74 Gy sul PTV1 (prostata e vescicole seminali prossimali), 65.8 Gy sul PTV2 (vescicole seminali distali) e 54 Gy sul PTV3 (linfonodi pelvici). Risultati: Sia con IMPT che con HT abbiamo ottenuto una copertura e una omogeneità di dose del target sovrapponibile. Oltre i 65 Gy, HT e IMPT erano equivalenti per il retto, mentre con l’IMPT c’era maggior risparmio della vescica e del bulbo penieno da 0 a 70 Gy. Da 0 fino a 60 Gy, i valori dosimetrici dell’IMPT erano molto più bassi per tutti gli organi a rischio (OARs), eccetto che per le teste femorali, dove la HT aveva un vantaggio dosimetrico rispetto all’IMPT nel range di dose 25-35 Gy. La dose media agli OARs era ridotta del 30-50% con l’IMPT. Conclusioni: Con le due tecniche di trattamento (HT e IMPT) si ottiene una simile distribuzione di dose nel target. Un chiaro vantaggio dosimetrico dell’IMPT sul HT è ottenuto dalle medie e basse dosi. Le attuali conoscenze sulle relazioni dose-effetto e sul risparmio delle madie e basse dosi con l’IMPT non sono ancora state quantificate dal punto di vista clinico.

Hypofractionated stereotactic radiotherapy after hyperbaric oxygenation for recurrent high-grade glioma: a pilot study

Purpose The presence of hypoxic cells in high-grade glioma (HGG) is one of the main reasons of local failure after radiotherapy (RT). The use of hyperbaric oxygen therapy (HBO) could help to overcome the problem of hypoxia in poorly oxygenated regions of the tumor. We performed a pilot study to evaluate the efficacy of hypofractionated image-guided helical TomoTherapy (HT) after HBO in the treatment of recurrent HGG (rHGG). Methods We enrolled 15 patients (aged >18 years) with diagnosis of rHGG. A total dose of 15-25 Gy was administered in daily 5-Gy fractions for 3-5 consecutive days after daily HBO. Each fraction was delivered up to maximum of 60 minutes after HBO. Results Median follow-up from HBO-RT was 28.6 (range: 5.3-56.8). No patient was lost to follow-up. Median progression-free survival (mPFS) for all patients was 3.2 months (95% CI: 1.34- 6.4 ), while 3-month, 6-month and 12 month PFS was 60% (95%CI: 31.8.4-79.7), 40% (95%CI: 16.5- 62.8) and10.0 (0.8-33.5) , respectively. Median overall survival (mOS) of HBO-RT was 11.7 months (95% CI: 7.3-29.3), while 3-month, 6-month and 12 month OS was 100% , 93.3% (61.3-99.0) and 46.7 % (21.2-68.8). No acute or late neurologic toxicity >grade 2 (CTCAE version 4.3) was observed in 86.66% of patients. Two patients developed G3 Radionecrosis. Conclusion HSRT combined to HBO seems effective and safe in the treatment of rHGG. One of advantages of HBO-RT is the reduced overall treatment time (3-5 consecutive days).

Ultra-hypofractionated stereotactic radiotherapy for prostate cancer in 5 fractions: current evidences and our clinical experience

AIMS: The present is a retrospective evaluation of acute genito-urinary (GU) and gastro-intestinal (GI) toxicity, in addition to biochemical recurrence rate in 57 prostate cancer patients treated at our Institution with ultra-hypofractionated RT (UHRT) schedule. METHODS: From January 2021 to December 2022 we have treated 57 patients with prostate cancer, using an UHRT scheme of 5-fractions every other day for a total dose delivered of 36.25 Gy, according to the PACE-B trial treatment schedule. Good urinary function, assessed by International Prostate Symptom Score (IPSS), were required. The simulation CT scans were acquired in supine position and fused with MRI for CTVs definition for every patient. Each treatment was performed by Accuray's TomoTherapy with daily IGRT. The evaluation of the set-up was very restrictive before daily treatment delivery. RESULTS: According to RTOG toxicity scale, the acute GU toxicity at 3 months from RT, GU toxicity was G0 for 30 patients (52.6%), G1 for 26 (45.6%) and G2 for one only (1.75%); rectal toxicity was G0 for 56 patients (98.25%) and G1 for one only (1.75%). The median follow-up (FU) was 9 months (2-24 months). In the following FU months, we observed progressively lower urinary and rectal toxicity, except for one patient who showed G2 GU toxicity at 12 months. All but one patient had a progressive PSA value decrease. CONCLUSIONS: In our experience, UHRT appears to be safe and well tolerated even without the use of rectal spacer devices. A longer FU is necessary to evaluate late toxicity and disease control rate.