Adherence to Contouring and Treatment Planning Requirements Within a Multicentric Trial: Results of the Quality Assurance of the SAKK 09/10 trial.

PURPOSE: To evaluate the results of the radiation therapy (RT) quality assurance (QA) program of the phase 3 randomized SAKK 09/10 trial in patients with biochemically recurrent prostate cancer after prostatectomy. METHODS AND MATERIALS: Within the Schweizerische Arbeitsgemeinschaft für Klinische Krebsforschung (SAKK) 09/10 trial testing 64-Gy versus 70-Gy salvage RT, a central collection of treatment plans was performed and thoroughly reviewed by a dedicated medical physicist and radiation oncologist. Adherence to the treatment protocol and specifically to the European Organization for the Research and Treatment of Cancer (EORTC) guidelines for target volume definition (classified as deviation observed yes vs no) and its potential correlation with acute and late toxicity (Common Terminology Criteria for Adverse Events version 4.0) and freedom from biochemical progression (FFBP) were investigated. RESULTS: The treatment plans for 344 patients treated between February 2011 and April 2014 depicted important deviations from the EORTC guidelines and the recommendations per trial protocol. For example, in up to half of the cases, the delineated structures deviated from the protocol (eg, prostate bed in 48.8%, rectal wall [RW] in 41%). In addition, variations in clinical target volume (CTV) and planning target volume (PTV) occurred frequently (eg, CTV and PTV deviations in up to 42.4% and 25.9%, respectively). The detected deviations showed a significant association with a lower risk of grade ≥2 gastrointestinal acute toxicity when the CTV did not overlap the RW versus when the CTV overlapped the RW (odds ratio [OR], 0.43; 95% confidence interval [CI], 0.22-0.85; P = .014), and a higher rate of grade ≥2 late genitourinary (GU) toxicity when the CTV overlapped the RW (OR, 2.58; 95% CI, 1.17-5.72; P = .019). A marginally significant lower risk of grade ≥2 late GU toxicity was observed when the prostate bed did not overlap versus did overlap the RW (OR, 0.51; 95% CI, 0.25-1.03; P = .06). In addition, a marginally significant decrease in FFBP was observed in patients with PTV not including surgical clips as potential markers of the limits of the prostate bed (hazard ratio, 1.44; 95% CI, 0.96-2.17; P = .07). CONCLUSIONS: Despite a thorough QA program, the central review of a phase 3 trial showed limited adherence to treatment protocol recommendations, which was associated with a higher risk of toxicity by means of acute or late gastrointestinal or GU toxicity and showed a trend toward worse FFBP. Data from this QA review might help to refine future QA programs and prostate bed delineation guidelines.

Two Birds with One Stone: Skull Base Meningioma and Jugulotympanic Paragangliomas with Somatostatin Receptor Positron Emission Tomography.

We describe the case of a 74-year-old female patient previously treated with radiation therapy for a meningioma of the skull base and with surgery for a right tympanic paraganglioma. After the morphological progression of the meningioma demonstrated by magnetic resonance imaging (MRI), the patient underwent somatostatin receptor positron emission tomography/computed tomography (SR-PET/CT) with Gallium-68 DOTATATE for restaging. This examination showed increased somatostatin receptor expression by the meningioma and confirmed its extension as already assessed by MRI (endocranial extension, skull base involvement and invasion of the right orbit). Furthermore, SR-PET/CT detected two small right jugulotympanic pararagangliomas with high somatostatin receptor expression. Lastly, SR-PET/CT demonstrated that this patient would be an ideal candidate for peptide receptor radionuclide therapy (PRRT) that can be used for the treatment of progressive/treatment-refractory meningiomas and relapsed paragangliomas with high somatostatin receptors expression, both conditions coexisting in this case.

Dose-intensified Versus Conventional-dose Salvage Radiotherapy for Biochemically Recurrent Prostate Cancer After Prostatectomy: The SAKK 09/10 Randomized Phase 3 Trial.

BACKGROUND: Salvage radiotherapy (SRT) is utilized for biochemical progression of prostate cancer after radical prostatectomy (RP). OBJECTIVE: To report the outcomes of the SAKK 09/10 trial comparing conventional and dose-intensified SRT. DESIGN, SETTING, AND PARTICIPANTS: SAKK 09/10 was a randomized, multicenter, phase 3 trial that recruited men with biochemical progression after RP. INTERVENTION: Patients were randomly assigned to conventional-dose (64 Gy) or dose-intensified SRT (70 Gy) to the prostate bed without hormonal therapy. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was freedom from biochemical progression (FFBP). Secondary endpoints included clinical progression-free survival (PFS), time to hormonal treatment, overall survival (OS), acute and late toxicity (Common Terminology Criteria for Adverse Events v4.0), and quality of life (QoL). RESULTS AND LIMITATIONS: Between February 2011 and April 2014, 350 patients were randomly assigned to 64 Gy (n = 175) or 70 Gy (n = 175). Median prostate-specific antigen at randomization was 0.3 ng/ml. After median follow-up of 6.2 yr, the median FFBP was 8.2 yr in the 64 Gy arm and 7.6 in the 70 Gy arm (log-rank p = 0.4), with a hazard ratio of 1.14 (95% confidence interval 0.82-1.60). The 6-year FFBP rates were 62% and 61%, respectively. No significant differences in clinical PFS, time to hormonal treatment, or OS were observed. Late grade 2 and 3 genitourinary toxicity was observed in 35 (21%) and 13 (7.9%) patients in the 64 Gy arm, and 46 (26%) and seven (4%) in the 70 Gy arm, respectively (p = 0.8). Late grade 2 and 3 gastrointestinal toxicity was observed in 12 (7.3%) and seven patients (4.2%) in the 64 Gy arm, and 35 (20%) and four (2.3%) in the 70 Gy arm, respectively (p = 0.009). There were no significant differences in QoL. CONCLUSIONS: Conventional-dose SRT to the prostate bed is sufficient in patients with early biochemical progression of prostate cancer after RP. PATIENT SUMMARY: The optimal radiation therapy dose for patients who have increased tumor markers after surgery for prostate cancer is unclear. We found that administering a higher dose only increased the gastrointestinal side effects without providing any benefits to the patient. This clinical trial is registered on ClinicalTrials.gov as NCT01272050.

Radiolabelled choline versus PSMA PET/CT in prostate cancer restaging: a meta-analysis.

Both radiolabelled choline and prostate specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) could be used in patients with biochemical recurrent prostate cancer (BRPCa). We aimed to perform a meta-analysis about the head-to-head comparison of detection rate (DR) between these methods in BRPCa. A comprehensive literature search of studies listed in PubMed/MEDLINE, EMBASE and Cochrane library databases through October 2018 and regarding the head-to-head comparison of DR between radiolabelled choline and PSMA PET/CT in BRPCa was carried out. Overall pooled DR was calculated on a per patient-based analysis; subgroup analyses taking into account different prostate-specific antigen (PSA) cut-off values were performed. Five studies (257 BRPCa patients) were included. The meta-analysis provided the following overall DR: 56% [95% confidence interval (95% CI): 37-75%] for radiolabelled choline PET/CT and 78% (95% CI: 70-84%) for radiolabelled PSMA PET/CT. Significant difference of DR was found only in patients with PSA ≤ 1 ng/ml [the DR of radiolabelled choline and PSMA PET/CT were 27% (95% CI: 17-39%) and 54% (95% CI: 43-65%), respectively]. Radiolabelled PSMA PET/CT proved to be clearly superior in detecting BRPCa lesions at low PSA levels (≤ 1 ng/ml) when compared to radiolabelled choline PET/CT. On the other hand, the superiority of radiolabelled PSMA PET/CT was less evident in patients with PSA > 1 ng/ml. More studies and in particular cost-effectiveness analyses comparing these imaging methods are warranted.