Strahlentherapie und Onkologie

Wirksamkeit und Sicherheit einer Kohlenstoffionentherapie lokal rezidivierter Rektumkarzinome: Ergebnisse der J‑CROS-Studie 1404 Rektum

Einfluss der prophylaktischen Ganzhirnbestrahlung auf das Gesamtüberleben von Patienten mit einem fortgeschrittenen nicht-kleinzelligen Bronchialkarzinom

Beim HPV-assoziierten Oropharynxkarzinom ist die Radiochemotherapie mit Cisplatin der Bioradiotherapie mit Cetuximab in Bezug auf das Gesamtüberleben überlegen

Endokrine Funktionsstörungen nach Bestrahlung von Hirntumoren bei Kindern und jungen Erwachsenen

Patient- versus physician-reported outcomes in prostate cancer patients receiving hypofractionated radiotherapy within a randomized controlled trial Abstract Purpose The risk of developing acute radiotherapy(RT)-induced side effects may increase with hypofractionated RT. To detect treatment-related side effects, patient-reported outcomes (PROs) might be more reliable than physician-reported outcomes. Therefore, we tried to evaluate the rate of agreement between urinary and gastrointestinal (GI) side effects and the prevalence of side effects reported by patients and by physicians. Methods Data from a randomized controlled trial (RCT) comparing two hypofractionated RT schedules were used. Urinary (nocturia, incontinence, frequency, dysuria, and urgency) and GI (obstruction, diarrhea, vomiting, nausea, bloating, hemorragia, and incontinence) symptoms measured by the EORTC QLQ-C30 and PR-25 were used for PROs. The same symptoms were scored by the physician using the Common Terminology Criteria Adverse Events v4.0. Outcomes were reported at baseline, end of treatment, month 1, and month 3. PROs and physician-reported outcomes were converted in two categories (0 = no symptoms; 1 = symptoms of any severity) and were correlated using the kappa (κ) correlation statistics. Values below 0.40 were considered low agreement. In addition, the prevalence of symptoms was calculated. Results Data from 160 patients were used. The mean value for Cohen's κ was 0.31 (ranging between 0.04 and 0.55) and 0.23 (ranging between 0.04 and 0.47) for urinary and GI symptoms, respectively. Except for three symptoms at baseline, all symptoms reported by patients were higher than those reported by physicians. Conclusion There is low agreement between symptoms reported by patients and physicians, with high rates of underreporting by the physician.

Dosimetric and volumetric effects in clinical target volume and organs at risk during postprostatectomy radiotherapy Abstract Purpose To assess the reproducibility of the dose–volume distribution of the initial simulation CT, generated using volumetric modulated arc therapy (VMAT) planning, during the radiotherapy of the prostatic bed based on weekly cone beam CTs (CBCT). Methods Twenty-three patients, after radical prostatectomy were treated with adjuvant or salvage radiotherapy between July and December 2016 and considered for this evaluation. Weekly CBCT scans (n = 138) were imported into the treatment planning system, and the clinical tumor volume (CTV), the rectum and the bladder were contoured. The initially calculated dose distribution and the dose–volume histograms generated from weekly CBCTs were compared. The prostatic fossa dose coverage was assessed by the proportion of the CTV fully encompassed by the 95% and 98% isodose lines. Rectal and bladder volumes receiving 50, 60 and 65 Gy during the treatment were compared to the initial plan, with statistical significance determined using the one-sample t‑test. Results Marked variations in the total organ volume of the rectum and the bladder were observed. The correlation between rectum volume and V50 was not significant (p = 0.487), while the bladder volume and V50 demonstrated a significant correlation. There was no correlation between urinary bladder volume and CTV. The change in rectal volume correlated significantly with CTV. The dose coverage (D98% and D95%) to the prostatic bed could be achieved for all patients due to the ventral shift in the volume differences of the rectum. Conclusion Weekly CBCTs can be considered as adequate verification tools to assess the interfractional variability of the CTV and organs at risk. The proven volume changes in the urinary bladder and the rectum do not compromise the final delivered dose in the CTV.

A fatal case of Fournier's gangrene during neoadjuvant radiotherapy for rectal cancer Abstract Purpose To report the development of an ultimately fatal occurrence of Fournier's gangrene in a rectal cancer patient undergoing neoadjuvant radiotherapy without chemotherapy. Methods A 53-year-old male patient with G2 cT3 cN1a cM0 stage IIIB adenocarcinoma of the lower rectum and several comorbidities including ulcerative colitis was treated with 56 Gy to the primary tumor in 28 fractions because he declined the recommended simultaneous chemotherapy. He was also enrolled in the ketogenic diet arm of our KETOCOMP study, so that prospective measurements of blood parameters, quality of life, and body composition were made. Results The patient died 6 days after completion of radiotherapy due to septic shock associated with Fournier's gangrene reaching from the right buttock into the gluteal muscles and descending into the scrotum. In retrospect, there were several signs probably indicating the development of the gangrene: (i) a decline in bioelectrical phase angle; (ii) an accelerated weight and fat-free mass loss starting in the third week of radiotherapy; (iii) an increase in C-reactive protein (CRP) and concurrent drop in high-density lipoprotein (HDL) cholesterol and insulin-like growth factor(IGF)-1 concentrations; and (iv) the occurrence of a sharp pain in the perianal region reported in the fifth week of radiotherapy. Notably, his self-reported quality of life score was the same at the end of as before radiotherapy. Conclusions This case highlights the occurrence of Fournier's gangrene as an extremely rare but life-threatening complication during neoadjuvant radiotherapy for rectal cancer which should be refreshed in the awareness of radiation oncologists and radiologists.

Comparison of 68  Ga-PSMA ligand PET/CT versus conventional cross-sectional imaging for target volume delineation for metastasis-directed radiotherapy for metachronous lymph node metastases from prostate cancer Abstract Purpose To assess the differences in the target volume (TV) delineation of metachronous lymph node metastases between 68 Ga-PSMA ligand PET/CT and conventional imaging in a comparative retrospective contouring study. Patients and methods Twenty-five patients with biochemical prostate cancer recurrence after primary prostatectomy underwent 68 Ga-PSMA ligand PET/CT in addition to conventional imaging techniques such as CT and/or MR imaging for restaging. All patients were diagnosed with at least one lymph node metastasis. TVs were manually delineated in two different ways: (a) based on conventional imaging (CT/MRI) and (b) based on conventional imaging (CT/MRI) plus 68 Ga-PSMA ligand PET/CT. The size of TVs, overlap rates, and subjective assessment of the difficulty of TV delineation reported by the radiation oncologist (easy/moderate/difficult) were compared. Results With the additional information from PSMA ligand PET, 47 lymph node metastases were identified and included in the gross tumor volume (GTV). The median clinical target volume (CTV) of non-PET-based TV delineation was statistically larger than the CTV based on PET imaging (134.8 ml [range 6.9–565.2] versus 44.9 ml [range 4.9–481.3; p = 0.001]). The CTV based on CT/MRI enclosed only 81.3% (39/48) of PET-positive lymph nodes. The CT/MRI-based CTV did not enclose all PET-positive lymph nodes in 24% (6/25) of patients. In 12% (3/25) of patients, all PET-positive lymph nodes were outside of the CT/MRI-based CTV. The median overlap rates (TVPET/TVCT/MRI × 100) were 45.7% (range 0–96.9) for the GTV and 71.7% (range 9.8–98.2) for the CTV. The assessment of difficulty of contouring revealed that contouring with the additional imaging information of the PET was categorized as easy/moderate in 92% (23/25) and as difficult in 8% (2/25) of the cases, whereas contouring based on CT/MRI without PET was categorized as difficult in 56% (14/25) and as easy/moderate in 44% of the cases (11/25; p = 0.003). Conclusion 68 Ga-PSMA ligand PET/CT is superior to conventional cross-sectional imaging for the delineation of lymph node metastases from prostate cancer. PET-based TV delineation allows for smaller target volumes and should be considered the standard for irradiation of metachronous lymph node metastases in recurrent prostate cancer. Conventional imaging is not sufficiently sensitive for radio-oncological treatment concepts in oligometastatic prostate cancer.

Impact of androgen deprivation therapy on apparent diffusion coefficient and T2w MRI for histogram and texture analysis with respect to focal radiotherapy of prostate cancer Abstract Purpose Accurate prostate cancer (PCa) detection is essential for planning focal external beam radiotherapy (EBRT). While biparametric MRI (bpMRI) including T2-weighted (T2w) and diffusion-weighted images (DWI) is an accurate tool to localize PCa, its value is less clear in the case of additional androgen deprivation therapy (ADT). The aim of this study was to investigate the value of a textural feature (TF) approach on bpMRI analysis in prostate cancer patients with and without neoadjuvant ADT with respect to future dose-painting applications. Methods 28 PCa patients (54–80 years) with (n = 14) and without (n = 14) ADT who underwent bpMRI with T2w and DWI were analyzed retrospectively. Lesions, central gland (CG), and peripheral zone (PZ) were delineated by an experienced urogenital radiologist based on localized pre-therapeutic histopathology. Histogram parameters and 20 Haralick TF were calculated. Regional differences (i. e., tumor vs. PZ, tumor vs. CG) were analyzed for all imaging parameters. Receiver-operating characteristic (ROC) analysis was performed to measure diagnostic performance to distinguish PCa from benign prostate tissue and to identify the features with best discriminative power in both patient groups. Results The obtained sensitivities were equivalent or superior when utilizing the TF in the no-ADT group, while specificity was higher for the histogram parameters. However, in the ADT group, TF outperformed the conventional histogram parameters in both specificity and sensitivity. Rule-in and rule-out criteria for ADT patients could exclusively be defined with the aid of TF. Conclusions The TF approach has the potential for quantitative image-assisted boost volume delineation in PCa patients even if they are undergoing neoadjuvant ADT.

Chemoradiotherapy for anal cancer: are we as good as we think? Abstract Definitive chemoradiotherapy (CRT) is the standard treatment for anal squamous cell carcinoma (ASCC). Data regarding treatment outcome according to TNM classification is scarce. Here, we review data of randomized trials and retrospective cohorts suggesting a poor 3‑year disease-free survival (DFS; or progression-free survival, PFS) of approximately 60%, or even lower, in patients with locally advanced T3–4 and/or N+ disease, while patients with T1–2N0 ASCC have 3‑year DFS/PFS rates exceeding 80%. These results are in line with our data in a cohort of 210 patients with ASCC treated with definitive 5‑fluorouracil/mitomycin C‑based CRT to a total dose of 50.4 Gy plus a boost of 3.6–10.8 Gy. The implications of these findings and the current trials testing radiotherapy dose escalation/de-escalation strategies are reported. Finally, we will discuss the strong rationale for testing immune checkpoint blockade (ICB) with CRT in clinical trials to improve results, especially in patients with advanced ASCC.