18F-choline PET/MRI on initial staging of prostate cancer. Impact on therapy approach. / La PET/RM con 18F-colina en el diagnóstico inicial del cáncer de próstata. Impacto en la estrategia terapéutica.

AIM: Evaluate the therapy impact of initial staging in patients diagnosed with prostate cancer by 18 F-choline PET/MRI hybrid technique. MATERIAL: A prospective study which included 31 patients diagnosed with prostate cancer; Gleason > 7; mean PSA 13.6 ng/mL (range 6.3-20.6). PET/MRI studies were acquired simultaneously with hybrid equipment (SIGNA.3T, GE) following intravenous injection of 185 ± 18.5MBq of 18F-choline: - Early/prostate imaging: PET emission + multiparametric MR: DIXON-T1-T2-diffusion-gadolinium. - Late/whole-body imaging: PET emission + MR: DIXON-T1-T2-diffusion-STIR sequences. Images were visually evaluated. SUV & ADC & textures were also calculated. Treatment selection was based upon Oncology Committee consensus decision. RESULTS: Procedure was well tolerated in all patients, and no artifacts were reported. MRI was superior in T staging in eight patients (25.8%) (Likert: 2-3), whereas PET increased MRI sensitivity in three patients (9.7%) (PIRADS: 3). PROSTATE LESION LOCATION: Peripheral 91.4%, transitional 8.6%. SUVmax threshold: 2.95: sensitivity 92.9%, specificity 66.7%. No correlation SUV vs. ADC. Better distinction between stage T2 vs. T3 using the DiscrLin model with NG = 16 (AUC 0.7767 ± 0.3386). PET was superior to T2 in textures analysis (0.588 vs. 0.412). Seventeen patients (54.8%) were staged ≥ T3, with surgical treatment being contraindicated. Fifteen patients (48.4%) presented with extra-prostatic disease: 8/31 oligometastatic and 7/31 multiple metastasis. Therapy approach following PET/MRI was: radical treatment in 24/31 patients (77.4%), 14 radical prostatectomy and 10 MRI-guided radiotherapy; systemic treatment in 7/31 patients (22.6%). CONCLUSION: 18F-choline PET/MRI had a complementary role for the T staging, with a high detection rate for NM infiltration. PET/MRI findings allowed patients to be directed either to prostatectomy or MRI-guided radiotherapy, and thus avoiding radicaltreatment in 22.6% of patients.

Radioterapia de rescate en pacientes con cáncer de próstata. Planificación, respuesta al tratamiento y pronóstico mediante PET/TC con 11C-colina / Salvage radiotherapy in prostate cancer patients. Planning, treatment response and prognosis using 11C-choline PET/CT

Objetivo. Evaluar el valor pronóstico de la respuesta terapéutica mediante 11C-colina PET/TC en pacientes con recidiva bioquímica de cáncer de próstata en los que la exploración ha indicado el tratamiento con radioterapia radioguiada. Método. Treinta y siete pacientes inicialmente tratados con prostatectomía, acudieron por recidiva bioquímica. La 11C-colina PET/TC permitió la detección de infiltración adenopática infradiafragmática. Todos ellos fueron seleccionados para radioterapia de intensidad modulada, escalando la dosis según los hallazgos de la PET/TC. Al año se les realizó PSA y 11C-colina PET/TC categorizando la respuesta (completa/parcial/progresión). Se efectuó seguimiento clínico/analítico/imagen hasta aparición de segunda recidiva o 36 meses en pacientes libres de enfermedad. Resultados. La 11C-colina PET/TC permitió la detección adenopática en los 37 pacientes. En 18 (48,6%) fue supracentimétrica y en 19 (51,3%) no había criterios patológicos por TC: 9 (24,3%) ganglios positivos supra + infracentimétricos y 10 (27,0%) únicamente infracentimétricos. Categorizamos la respuesta mediante 11C-colina PET/TC un año tras la radioterapia: 16 pacientes (43,2%) respuesta completa; 15 (40,5%) respuesta parcial; 6 (16,2%) progresión. La respuesta fue concordante entre PSA y 11C-colina PET/TC en 32 pacientes (86,5%) y discordante en 5 (13,5%). Se detectó nueva recidiva en 12 pacientes (80%) con respuesta parcial y en 5 (31,2%) con respuesta completa. La media de tiempo libre de enfermedad ha sido 9 meses tras respuesta parcial y 18 meses tras respuesta completa (diferencia significativa, p < 0,0001). Conclusión. La 11C-colina PET/TC permite la selección de los pacientes con recidiva de cáncer de próstata candidatos a radioterapia, planificando la misma. La evaluación de la respuesta terapéutica mediante 11C-colina PET/TC presenta significación pronóstica (AU)

Objective. To assess the prognostic value of the therapeutic response by 11C-choline PET/CT in prostate cancer patients with biochemical recurrence in which 11C-choline PET/CT indicated radio-guided radiotherapy. Methods. The study included 37 patients initially treated with prostatectomy, who were treated due to biochemical recurrence. 11C-choline PE/CT detected infra-diaphragmatic lymph-node involvement. All were selected for intensity modulated radiation therapy, escalating the dose according to the PET findings. One year after treatment patients underwent PSA and 11C-choline PET/CT categorizing response (complete/partial/progression). Clinical/biochemical/image monitoring was performed until appearance of second relapse or 36 months in disease-free patients. Results. 11C-choline PET/CT could detect lymph nodes in all 37 patients. They were 18 (48.6%) of more than a centimetre in size and 19 (51.3%) with no pathological CT morphology: 9 (24.3%) with positive lymph nodes of around one centimetre and 10 (27.0%) only less than a centimetre in size. The response by 11C-choline PET/CT was categorised one year after radiotherapy: 16 patients (43.2%) complete response; 15 (40.5%) partial response, and 6 (16.2%) progression. The response was concordant between the PSA result and 11C-choline PET/CT in 32 patients (86.5%), and discordant in five (13.5%). New recurrence was detected in 12 patients (80%) with partial response, and 5 (31.2%) with complete response. The mean time to recurrence was 9 months after partial response, and 18 months after complete response (significant difference, p<.0001). Conclusion. 11C-choline PET/CT allows the selection of patients with recurrent prostate cancer candidates for radiotherapy and to plan the technique. The evaluation of therapeutic response by 11C-choline PET/CT has prognostic significance (AU)

Peritoneal Cancer Index by (18)F-FDG PET/TC pre and post-hyperthermic intraperitoneal chemotherapy. Report of a case. / Peritoneal Cancer Index mediante (18)F-FDG PET/TC pre y poscirugía citorreductiva radical y quimioterapia intraperitoneal con hipertermia. A propósito de un caso.

Radical cytoreductive surgery followed by hyperthermic intraperitoneal chemotherapy increases survival in patients with end-stage peritoneal carcinomatosis, and who are under palliative therapy. The Peritoneal Cancer Index enables the tumor burden to be quantified during surgery, as well as treatment planning and patient prognosis. It is obtained by combining the tumor spread in 13 abdominal and pelvic regions with the largest tumor size. Fluorodeoxyglucose positron emission tomography/computed tomography is the technique of choice for those patients selected to undergo radical cytoreductive surgery followed by hyperthermic intraperitoneal chemotherapy, due to its higher detection rate of carcinomatosis, and since it allows extra-peritoneal disease staging. The simplified Peritoneal Cancer Index (9 regions defined by 2 transverse and 2 sagittal planes) obtained by fluorodeoxyglucose positron emission tomography/computed tomography allows correlation with the surgical procedure, therefore its standardization is advisable.