To report the long-term results of the French Genitourinary Study Group (GETUG)-01 study in terms of event-free survival (EFS) and overall survival (OS) and assess the potential interaction between ...hormonotherapy and pelvic nodes irradiation.
Between December 1998 and June 2004, 446 patients with T1b-T3, N0pNx, M0 prostate carcinoma were randomly assigned to either pelvic nodes and prostate or prostate-only radiation therapy. Patients were stratified into 2 groups: "low risk" (T1-T2 and Gleason score 6 and prostate-specific antigen <3× the upper normal limit of the laboratory) (92 patients) versus "high risk" (T3 or Gleason score >6 or prostate-specific antigen >3× the upper normal limit of the laboratory). Short-term 6-month neoadjuvant and concomitant hormonal therapy was allowed only for high-risk patients. Radiation therapy was delivered with a 3-dimensional conformal technique, using a 4-field technique for the pelvic volume (46 Gy). The total dose recommended to the prostate moved from 66 Gy to 70 Gy during the course of the study. Criteria for EFS included biologic prostate-specific antigen recurrences and/or a local or metastatic progression.
With a median follow-up of 11.4 years, the 10-year OS and EFS were similar in the 2 treatment arms. A higher but nonsignificant EFS was observed in the low-risk subgroup in favor of pelvic nodes radiation therapy (77.2% vs 62.5%; P=.18). A post hoc subgroup analysis showed a significant benefit of pelvic irradiation when the risk of lymph node involvement was <15% (Roach formula). This benefit seemed to be limited to patients who did not receive hormonal therapy.
Pelvic nodes irradiation did not statistically improve EFS or OS in the whole population but may be beneficial in selected low- and intermediate-risk prostate cancer patients treated with exclusive radiation therapy.
Whole brain radiation therapy (WBRT) is an effective treatment in brain metastases and, when combined with local treatments such as surgery and stereotactic radiosurgery, gives the best brain ...control. Nonetheless, WBRT is often omitted after local treatment due to its potential late neurocognitive effects. Publications on radiation-induced neurotoxicity have used different assessment methods, time to assessment, and definition of impairment, thus making it difficult to accurately assess the rate and magnitude of the neurocognitive decline that can be expected. In this context, and to help therapeutic decision making, we have conducted this literature review, with the aim of providing an average incidence, magnitude and time to occurrence of radio-induced neurocognitive decline. We reviewed all English language published articles on neurocognitive effects of WBRT for newly diagnosed brain metastases or with a preventive goal in adult patients, with any methodology (MMSE, battery of neurcognitive tests) with which baseline status was provided. We concluded that neurocognitive decline is predominant at 4 months, strongly dependant on brain metastases control, partially solved at later time, graded 1 on a SOMA-LENT scale (only 8% of grade 2 and more), insufficiently assessed in long-term survivors, thus justifying all efforts to reduce it through irradiation modulation.
Conventional external-beam radiation therapy is dedicated to the treatment of localized disease, whereas radioimmunotherapy represents an innovative tool for the treatment of local or diffuse tumors. ...Radioimmunotherapy involves the administration of radiolabeled monoclonal antibodies that are directed specifically against tumor-associated antigens or against the tumor microenvironment. Although many tumor-associated antigens have been identified as possible targets for radioimmunotherapy of patients with hematological or solid tumors, clinical success has so far been achieved mostly with radiolabeled antibodies against CD20 ((131)I-tositumomab and (90)Y-ibritumomab tiuxetan) for the treatment of lymphoma. In this Review, we provide an update on the current challenges aimed to improve the efficacy of radioimmunotherapy and discuss the main radiobiological issues associated with clinical radioimmunotherapy.
The ACCORD 12 trial investigated the value of two different preoperative chemoradiotherapy (CT-RT) regimens in T3-4 Nx M0 resectable rectal cancer. Clinical results are reported after follow-up of 3 ...years.
Between November 2005 and July 2008, a total of 598 patients were randomly assigned to preoperative CT-RT with CAP45 (45-Gy RT for 5 weeks with concurrent capecitabine) or CAPOX50 (50-Gy RT for 5 weeks with concurrent capecitabine and oxaliplatin). Total mesorectal excision was planned 6 weeks after CT-RT. The primary end point was sterilization of the operative specimen, which was achieved in 13.9% versus 19.2% of patients, respectively (P = .09). Clinical results were analyzed for all randomly assigned patients according to the intention-to-treat principle.
At 3 years, there was no significant difference between CAP45 and CAPOX50 (cumulative incidence of local recurrence, 6.1% v 4.4%; overall survival, 87.6% v 88.3%; disease-free survival, 67.9% v 72.7%). Grade 3 to 4 toxicity was reported in four patients in the CAP45 group and in two patients in the CAPOX50 group. Bowel continence, erectile dysfunction, and social life disturbance were not different between groups. In multivariate analysis, the sterilization rate (Dworak score) of the operative specimen was the main significant prognostic factor (hazard ratio, 0.32; 95% CI, 0.21 to 0.50).
At 3 years, no significant difference in clinical outcome was achieved with the intensified CAPOX regimen. When compared with other recent randomized trials, these results indicate that concurrent administration of oxaliplatin and RT is not recommended.
Neoadjuvant chemoradiotherapy is considered a standard approach for T3-4 M0 rectal cancer. In this situation, we compared neoadjuvant radiotherapy plus capecitabine with dose-intensified radiotherapy ...plus capecitabine and oxaliplatin.
We randomly assigned patients to receive 5 weeks of treatment with radiotherapy 45 Gy/25 fractions with concurrent capecitabine 800 mg/m(2) twice daily 5 days per week (Cap 45) or radiotherapy 50 Gy/25 fractions with capecitabine 800 mg/m(2) twice daily 5 days per week and oxaliplatin 50 mg/m(2) once weekly (Capox 50). The primary end point was complete sterilization of the operative specimen (ypCR).
Five hundred ninety-eight patients were randomly assigned to receive Cap 45 (n = 299) or Capox 50 (n = 299). More preoperative grade 3 to 4 toxicity occurred in the Capox 50 group (25 v 1%; P < .001). Surgery was performed in 98% of patients in both groups. There were no differences between groups in the rate of conservative surgery (75%) or postoperative deaths at 60 days (0.3%). The ypCR rate was 13.9% with Cap 45 and 19.2% with Capox 50 (P = .09). When ypCR was combined with yp few residual cells, the rate was respectively 28.9% with Cap 45 and 39.4% with Capox 50 (P = .008). The rate of positive circumferential rectal margins (between 0 and 2 mm) was 19.3% with Cap 45 and 9.9% with Capox 50 (P = .02).
The benefit of oxaliplatin was not demonstrated and this drug should not be used with concurrent irradiation. Cap 50 merits investigation for T3-4 rectal cancers.
Pancreatic carcinoma is one of the leading causes of cancer-related mortality. At time of diagnosis, 30% of patients present with a locally advanced unresectable but nonmetastatic pancreatic ...carcinoma (LAPC). The French program Standards, Options, and Recommendations was promoted to conduct a qualitative systematic review to evaluate the role of radiotherapy in patients with LAPC.
A search to identify eligible studies was undertaken using the MEDLINE database. All phase III randomized trials and systematic reviews evaluating the role of radiotherapy in LAPC were included, together with some noncontrolled studies if no phase III trials were retrieved. The quality and clinical relevance of the studies were evaluated using validated checklists, which allowed associating each result with a level of evidence.
Twenty-one studies were included, as follows: two meta-analyses, 13 randomized trials, and six nonrandomized trials. Chemoradiotherapy increases overall survival when compared with best supportive care (level of evidence C) or with exclusive radiotherapy (level B1), but is more toxic (level B1). Chemoradiotherapy is not superior to chemotherapy in terms of survival (level B1) and increases toxicity (level A). Recent data favor limited irradiation to the tumor volume (level C). Fluorouracil is still the reference chemotherapy in association with radiotherapy (level B1). Induction chemotherapy before chemoradiotherapy improves survival (level C).
No standard treatment exists, but there are two options for treatment of LAPC; these are gemcitabine-based chemotherapy and chemoradiotherapy. Induction chemotherapy followed by a chemoradiotherapy is a promising strategy for selection of patients without early metastatic/progressing disease.
The role of adjuvant chemoradiotherapy (CRT) in resectable pancreatic cancer is still debated. This randomized phase II intergroup study explores the feasibility and tolerability of a ...gemcitabine-based CRT regimen after R0 resection of pancreatic head cancer.
Within 8 weeks after surgery, patients were randomly assigned to receive either four cycles of gemcitabine (control arm) or gemcitabine for two cycles followed by weekly gemcitabine with concurrent radiation (50.4 Gy; CRT arm). The primary objective was to exclude a < 60% treatment completion and a > 40% rate of grade 4 hematologic or GI toxicity in the CRT arm with type I and II errors of 10%. Secondary end points were late toxicity, disease-free survival (DFS), and overall survival (OS).
Between September 2004 and January 2007, 90 patients were randomly assigned (45:45). Patient characteristics were similar in both arms. Treatment was completed per protocol by 86.7% and 73.3% (80% CI, 63.1% to 81.9%; 95% CI, 58.1% to 85.4%) in the control and CRT arms, respectively, and grade 4 toxicity was 0% and 4.7% (two of 43; 80% CI, 1.2% to 11.9%), respectively. In the CRT arm, three patients experienced grade 3-related late toxicity. Median DFS was 12 months in the CRT arm and 11 months in the control arm. Median OS was 24 months in both arms. First local recurrence was less frequent in the CRT arm (11% v 24%).
Adjuvant gemcitabine-based CRT is feasible, well-tolerated, and not deleterious; adding this treatment to full-dose adjuvant gemcitabine after resection of pancreatic cancer should be evaluated in a phase III trial.
Pancreatic carcinoma is a leading cause of cancer-related mortality. Approximately 30% of pancreatic cancer patients present with locally advanced, unresectable nonmetastatic disease. For these ...patients, two therapeutic options exist: systemic chemotherapy or chemoradiotherapy. Within this context, the optimal technique for pancreatic irradiation is not clearly defined. A search to identify relevant studies was undertaken using the Medline database. All Phase III randomized trials evaluating the modalities of radiotherapy in locally advanced pancreatic cancer were included, as were some noncontrolled Phase II and retrospective studies. An expert panel convened with members of the Radiation Therapy Oncology Group and GERCOR cooperative groups to review identified studies and prepare the guidelines. Each member of the working group independently evaluated five endpoints: total dose, target volume definition, radiotherapy planning technique, dose constraints to organs at risk, and quality assurance. Based on this analysis of the literature, we recommend either three-dimensional conformal radiation therapy or intensity-modulated radiation therapy to a total dose of 50 to 54 Gy at 1.8 to 2 Gy per fraction. We propose gross tumor volume identification to be followed by an expansion of 1.5 to 2 cm anteriorly, posteriorly, and laterally, and 2 to 3 cm craniocaudally to generate the planning target volume. The craniocaudal margins can be reduced with the use of respiratory gating. Organs at risk are liver, kidneys, spinal cord, stomach, and small bowel. Stereotactic body radiation therapy should not be used for pancreatic cancer outside of clinical trials. Radiotherapy quality assurance is mandatory in clinical trials. These consensus recommendations are proposed for use in the development of future trials testing new chemotherapy combinations with radiotherapy. Not all of these recommendations will be appropriate for trials testing radiotherapy dose or dose intensity concepts.
Late fibrosis can occur in breast cancer patients treated with curative-intent radiotherapy. Predicting this toxicity is of clinical interest in order to adapt the irradiation dose delivered. ...Radiation-induced CD8 T-lymphocyte apoptosis (RILA) had been proven to be associated with less grade ≥2 late radiation-induced toxicities in patients with miscellaneous cancers. Tobacco smoking status and adjuvant hormonotherapy were also identified as potential factors related to late-breast-fibrosis-free survival. This article evaluates the predictive performance of the RILA using a ROC curve analysis that takes into account the dynamic nature of fibrosis occurrence. This time-dependent ROC curve approach is also applied to evaluate the ability of the RILA combined with the other previously identified factors. Our analysis includes a Monte Carlo cross-validation procedure and the calculation of an expected cost of misclassification, which provides more importance to patients who have no risk of late fibrosis in order to be able to treat them with the maximal irradiation dose. Performance evaluation was assessed at 12, 24, 36 and 50 months. At 36 months, our results were comparable to those obtained in a previous study, thus underlying the predictive power of the RILA. Based on specificity and cost, RILA alone seemed to be the most performant, while its association with the other factors had better negative predictive value results.
Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer characterized by poor response to chemotherapy and radiotherapy due to the lack of efficient therapeutic tools and early diagnostic ...markers. We previously generated the nonligand competing anti‐HER3 antibody 9F7–F11 that binds to pancreatic tumor cells and induces tumor regression in vivo in experimental models. Here, we asked whether coupling 9F7–F11 with a radiosensitizer, such as monomethylauristatin E (MMAE), by using the antibody‐drug conjugate (ADC) technology could improve radiation therapy efficacy in PDAC. We found that the MMAE‐based HER3 antibody‐drug conjugate (HER3‐ADC) was efficiently internalized in tumor cells, increased the fraction of cells arrested in G2/M, which is the most radiosensitive phase of the cell cycle, and promoted programmed cell death of irradiated HER3‐positive pancreatic cancer cells (BxPC3 and HPAC cell lines). HER3‐ADC decreased the clonogenic survival of irradiated cells by increasing DNA double‐strand break formation (based on γH2AX level), and by modulating DNA damage repair. Tumor radiosensitization with HER3‐ADC favored the inhibition of the AKT‐induced survival pathway, together with more efficient caspase 3/PARP‐mediated apoptosis. Incubation with HER3‐ADC before irradiation synergistically reduced the phosphorylation of STAT3, which is involved in chemoradiation resistance. In vivo, the combination of HER3‐ADC with radiation therapy increased the overall survival of mice harboring BxPC3, HPAC cell xenografts or patient‐derived xenografts, and reduced proliferation (KI67‐positive cells). Combining auristatin radiosensitizer delivery via an HER3‐ADC with radiotherapy is a new promising therapeutic strategy in PDAC.
What's new?
In pancreatic ductal adenocarcinoma (PDAC), chemoradiation is prescribed to patients with borderline resectable lesions to make surgery possible. The HER3 receptor is a key signaling hub in PDAC. Here, the authors developed a novel antibody‐drug conjugate targeting HER3 (HER3‐ADC) that enhanced radiosensitivity of PDAC by arresting cells in G2/M. HER3‐ADC increased radiation response in mice xenografted with PDAC cells, through inhibition of cell survival and induction of DNA break formation and apoptosis. Combining auristatin radiosensitizer delivery via an HER3‐ADC with radiotherapy could help increase the rate of resection for patients with borderline resectable pancreatic cancer.
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