Initial experience with stereotactic body radiation therapy for localized prostate cancer using helical tomotherapy.

PURPOSE: Single-institution single-arm prospective study. Endpoint: To assess whether there are more than 5 % of men having grade 3 GU or any grade 3 GI acute toxicity during stereotactic body radiation therapy (SBRT) for prostate cancer using helical tomotherapy. METHODS: Since May 2012, 17 prostate cancer patients were treated with helical tomotherapy. The exclusion criteria used are the following: Gleason score ≥8, PSA >20 ng/ml, cT3b-4, IPSS ≥20 and history of acute urinary retention. CTV included the prostate gland and 1 cm of seminal vesicles in the low-risk group (LR) or the seminal vesicles completely in the intermediate (IR) and high-risk (HR) NCCN groups. CTV margins ranged from 2 to 8 mm, while PTV margins were 2 to 9 mm. Patients received eight fractions of 5.48 Gy (LR) or 5.65 Gy (IR, HR) on alternate days. Total equivalent doses at 2 Gy per fraction are 87.4 for LR and 92.3 Gy for IR-HR using an α/ß value of 1.5. Correspondent figures for a α/ß of 3 are 74.3 Gy and 78.2 Gy, respectively. Megavoltage CT (MVCT) for on-line correction was taken before every fraction. RESULTS: The patient distribution by risk group is 29, 47 and 24 % for LR, IR and HR, respectively. 82 % received neoadjuvant-concomitant hormonal therapy. Acute GU toxicity grade 1, 2 and 3 was found in 70, 6 and 0 % of men. GI toxicity was observed in 50, 0 and 0. After 136 MVCT, the standard deviation of the mean individual corrections in the anterior-posterior direction was 2.5 mm. CONCLUSION: SBRT for prostate cancer using helical tomotherapy is feasible. Initial results show an early toxicity profile no worse than SBRT delivered with robotic radiosurgery or conventionally fractionated radiotherapy.

Prognostic factors for acute toxicity in prostate cancer patients treated with high-dose hypofractionated radiotherapy.

PURPOSE: To prospectively study acute genitourinary (GU) and gastrointestinal (GI) toxicity during hypofractionated radiotherapy. PATIENTS AND MATERIALS: One-hundred and seventy-one consecutive men with cT1-T3cN0cM0 prostate cancer were treated at 2.6 Gy/fraction to a total dose of 67.6 for low risk (EQD2 = 79 Gy) and 70.2 Gy for intermediate-high risk (EQD2 = 82 Gy) over 5.2-5.4 weeks (α/ß 1.5). Acute toxicity was scored according to RTOG/EORTC toxicity extended criteria after completing a 22-item questionnaire (basal, weekly, at 6 months). RESULTS: Minimum and median follow-up were 36 and 54.2 months, respectively. GU toxicity grades 0, 1, 2 and 3 were found in 30.4, 37, 32 and 0.6 % of patients, respectively. The figures for grades 0, 1, 2 and 3 GI toxicity were 66, 24, 10 and 0 %. The highest degree of acute reactions was reached at 4-5 weeks. At 6 months, 15 % of patients had GU toxicity (11 % grade 1, 4 % grade 2) and 5.8 % GI toxicity (5.3 % grade 1, 0.5 % grade 2). Multivariate analysis shows that bladder volume receiving ≥65 Gy (V 65) is associated with an increased risk of GU complications (p = 0.017, HR = 1.143, 95 % CI = 1.025-1.276), while history of TURP is linked to lower risk (p = 0.002, HR = 0.310, 95 % CI 0.004-0.370). Mean rectal dose (p = 0.013, HR = 1.089, 95 % CI 1.018-1.116) and total dose (p = 0.019, HR = 0.734, 95 % CI 0.567-0.950) are significantly related to GI toxicity. CONCLUSIONS: This 5-week dose-escalation hypofractionated radiotherapy schedule that uses 3D-conformal radiotherapy without IGRT has resulted in <1 % grade 3 acute complications. Our study suggests that reducing the mean rectal dose and the bladder V 65 helps prevent acute toxicity. TURP before radiotherapy was associated with lower acute GU toxicity.

Utilidad de la PET-TAC en la planificación radioterápica en el cáncer de cabeza y cuello. Nuestra experiencia inicial / Utility of PET-CT on radiotherapy planning of head and neck cancer. Our initial experience

Objetivo. Describir los métodos aplicados en la incorporación de la PET-TAC en la planificación de radioterapia (RT) en pacientes afectos de tumores de cabeza y cuello, así como valorar el impacto que induce en la estadificación y en la estimación de volúmenes para irradiar. Material y método. Estudio prospectivo en el que se incluyeron 20 pacientes afectos de un tumor localizado en el área de la cabeza y del cuello y candidatos a tratamiento radioterápico. Todos ellos se sometieron a un estudio PET-TAC (GEDSTE 16) de cuerpo completo para estadificar o reestadificar y a otro estudio selectivo cervical tardío (3h) para la planificación del tratamiento. En este último se utilizó la TAC con protocolo diagnóstico, una mesa réplica de la utilizada en RT y una máscara personalizada. Se evaluó la afectación ganglionar y/o a distancia, atendiendo a cambios en el estadio. También se compararon los volúmenes obtenidos entre las distintas técnicas. El valor umbral del standard uptake value (SUV) para definir el volumen tumoral de la PET se estableció de modo empírico y osciló entre un 20–40% del SUV máximo. Resultados. Desde octubre de 2007 hasta agosto de 2008 se han realizado planificaciones de RT con PET-TAC en 20 pacientes. Se han analizado un total de 29 lesiones (18 lesiones primarias, ya que 2 pacientes fueron excluidos por no evidenciar tumor en el estudio PET o TAC, y 11 ganglios). La localización más frecuente del tumor primario ha sido la orofaringe (5 pacientes). El SUV máximo promedio de las lesiones ha sido de 14,4 (rango: 5,0–26,4). Los valores promedio del volumen tumoral con PET y con TAC han sido 21,9 y 19,3cm3, respectivamente, no evidenciando diferencias estadísticamente significativas. La PET-TAC modificó la estadificación en el 20% de los casos, mostrando un impacto diagnóstico y terapéutico global del 50 y del 25%, respectivamente...(AU)

Objective. To describe the methods used for the incorporation of FDG-PET-CT on radiotherapy planning of patients with head and neck cancer and also to evaluate the impact of FDG-PET-CT on staging and tumor volume definition. Material and methods. A prospective study in which 20 patients with head and neck tumor submitted for radiotherapy treatment were included. All underwent a whole body PET- CT (GE DSTE 16) for staging and restaging, also acquiring an additional 3h delayed PET image with diagnostic CT parameters for planning. A CT scan with diagnostic protocol, tabletop available for radiotherapy treatment and the same personalized head-shoulder mask were used in the latter. Lymph node involvement and/or distant involvement were evaluated, considering the changes in staging. We also evaluated the differences in volumes obtained between the different techniques. The threshold value used for delineating PET gross tumor volume (GTV) was empirically established and ranged from 20–40% of the maximum SUV. Results. Radiotherapy planning was performed with PET-CT in 20 patients between October 2007 to September 2008. A total of 29 lesions (18 primary lesions because 2 patients were excluded as no tumor was observed on the PET CT images, and 11 nodes). The most frequent location was oropharynx (5 patients). Mean maxSUV of the 29 lesions was 14.4 (range 5.0 and 26.4). No statistically significant differences were found between the GTV PET and GTV CT (mean 21.9cm3 and 19.3cm3, respectively). PET-CT modified the staging in 20% of the patients, with a diagnostic and therapeutic impact of 50 and 25%, respectively...(AU)

[Utility of PET-CT on radiotherapy planning of head and neck cancer. Our initial experience]. / Utilidad de la PET-TAC en la planificación radioterápica en el cáncer de cabeza y cuello. Nuestra experiencia inicial.

OBJECTIVE: To describe the methods used for the incorporation of FDG-PET-CT on radiotherapy planning of patients with head and neck cancer and also to evaluate the impact of FDG-PET-CT on staging and tumor volume definition. MATERIAL AND METHODS: A prospective study in which 20 patients with head and neck tumor submitted for radiotherapy treatment were included. All underwent a whole body PET- CT (GE DSTE 16) for staging and restaging, also acquiring an additional 3h delayed PET image with diagnostic CT parameters for planning. A CT scan with diagnostic protocol, tabletop available for radiotherapy treatment and the same personalized head-shoulder mask were used in the latter. Lymph node involvement and/or distant involvement were evaluated, considering the changes in staging. We also evaluated the differences in volumes obtained between the different techniques. The threshold value used for delineating PET gross tumor volume (GTV) was empirically established and ranged from 20-40% of the maximum SUV. RESULTS: Radiotherapy planning was performed with PET-CT in 20 patients between October 2007 to September 2008. A total of 29 lesions (18 primary lesions because 2 patients were excluded as no tumor was observed on the PET CT images, and 11 nodes). The most frequent location was oropharynx (5 patients). Mean maxSUV of the 29 lesions was 14.4 (range 5.0 and 26.4). No statistically significant differences were found between the GTV PET and GTV CT (mean 21.9cm³ and 19.3cm³, respectively). PET-CT modified the staging in 20% of the patients, with a diagnostic and therapeutic impact of 50 and 25%, respectively. CONCLUSION: The incorporation of PET-CT in routine radiotherapy planning is a promising technique that requires close collaboration between the nuclear medicine and radiotherapy oncology departments. PET-CT achieves better staging in patients and has a significant diagnostic and therapeutic impact. The use of the hybrid technique avoids problems arising from co-registry as well as a second examination for planning with the consequent advantage for the patient. Nonetheless, more prospective and randomized studies with pathology specimens are needed to evaluate the real impact in the tumor volume definition.