Long-Term Outcomes of NRG/RTOG 0126, a Randomized Trial of High Dose (79.2 Gy) vs. Standard Dose (70.2 Gy) Radiation Therapy (RT) for Men with Localized Prostate Cancer

PURPOSE/OBJECTIVE(S)

NRG/RTOG 0126, a phase III trial for men with localized prostate cancer testing whether dose escalation to 79.2 Gy with 3DCRT/IMRT improved overall survival (OS). Long-term results of this trial are presented.

MATERIALS/METHODS

Patients with clinical stage T1b-T2b and either Gleason Score (GS) 2-6 and 10 ≤ PSA < 20 or GS 7 and PSA < 15 were eligible and randomized to receive 79.2 Gy or 70.2 Gy. No previous or concurrent androgen withdrawal therapy was administered. Treatment was delivered with 3DCRT/IMRT to a dose of 79.2 Gy in 44 fractions or 70.2 Gy in 39 fractions to the PTV encompassing the prostate and seminal vesicles. Image guidance was not required. ASTRO and Phoenix definitions were used for biochemical failure (ABF and PBF, respectively). OS was estimated by the Kaplan-Meier method and arms compared with the log-rank test. ABF, PBF, local progression (LP), distant metastases (DM) and time to late GI/GU toxicities were estimated by the cumulative incidence method and arms compared with Gray's test.

RESULTS

One thousand five hundred thirty-two men were randomized, 763 to 79.2 Gy and 769 to 70.2 Gy. 1499 were eligible, 748 and 751 in the 79.2 Gy and 70.2 Gy arms respectively. Median age was 71, 70% had PSA < 10 ng/ml, 84% with GS 7, 57% had T1 disease, and 66% treated with 3D-CRT. Outcomes are shown in the TABLE: . With a median follow up of 12 years, there was no significant difference in OS. There was a statistically significant decrease in the cumulative incidence of ABF, PBF, DM, LP, and salvage therapies in the 79.2 Gy arm. There were significantly higher rates of grade 2+ GI and GU toxicity in the 79.2 Gy arm. There were no statistically significant differences in the rates of grade 3+ GU or GI toxicity between either arm.

CONCLUSION

Long term follow up confirms no improvement in OS with dose escalation in this study population. However, there are significant improvements in ABF, PBF, DM, LP, and need for salvage therapy. Despite the use of more salvage therapy in the low dose arm, dose escalated RT resulted in lower rates of DM, a clinically relevant endpoint. Patients receiving dose escalation do experience a higher rate of grade 2+ GU and GI toxicity but no worse grade 3+ toxicities.

Radiotherapy for Liver Cancer: An International Multi-Centre Pooled Analysis of 925 Cases

PURPOSE/OBJECTIVE(S)

Primary and secondary liver cancer incidence is growing and has a poor prognosis. The standard use of radiation has been hampered by studies with a wide range of patients, different management protocols and varied outcomes. To overcome this heterogeneity in the literature, larger and higher-level trials are warranted, but, so far, have been difficult to implement. Therefore, pooled analyses may offer the best way to determine the benefit of radiation, identify treatment parameters needed to optimize treatment techniques, and identify patient factors that allow for better patient selection.

MATERIALS/METHODS

Patients with liver cancer treated by radiotherapy at centers in Canada, United States and Australia was pooled. Patient and treatment characteristics were noted, as well as the clinical outcomes of local control within 1 year, recurrence and mortality. Stepwise Cox proportional hazards models were used to identify significant predictors for recurrence and mortality. Patients were stratified by center, and primary versus metastatic disease.

RESULTS

A total of 925 patients were included in this study. Mean age was 67 years, and 45% had a primary diagnosis of hepatocellular carcinoma. 1-year local control rate was 80%. Median survival was 1.8 years (1.9 years for primary liver cancer, and 1.4 years for metastatic liver cancer). Higher total dose and BED was associated with better survival. Median time to recurrence was 1.5 years. Higher total dose was associated with lower risk of recurrence CONCLUSION: As one of the largest pooled analyses in hepatic cancer, this international multi-center study provides pragmatic data on clinical outcomes of patients receiving radiotherapy for liver cancer. This database may assist in better selection of patients for future studies and answer questions such as what is the optimal dose and which patients benefit from treatment.

Stereotactic Ablative Radiotherapy for Oligo-Progressive Cancers: Results of the Randomized Phase II STOP Trial

PURPOSE/OBJECTIVE(S)

In the metastatic setting, there is uncertain benefit to localized eradication of one or more lesions that are progressing despite systemic therapy. This randomized phase II trial examined if patients with ≤5 sites of oligoprogression benefited from the addition of stereotactic ablative radiotherapy (SABR) to standard of care (SOC) systemic therapy.

MATERIALS/METHODS

Eligibility criteria included age ≥18 years, ECOG performance status 0-2, and oligoprogressive disease, defined as 1-5 lesions actively progressing while on systemic therapy. Patients were required to have at least 3 months of disease stability/response on systemic therapy prior to oligoprogression. After stratifying by type of systemic therapy (cytotoxic vs. non-cytotoxic), patients were randomized 2:1 to SABR to all progressing lesions plus SOC (SABR arm) vs. SOC alone (SOC arm). The trial began exclusive to non-small cell lung cancer but did not meet accrual goals and was expanded in 2019 to include all non-hematologic malignancies. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), lesional control, quality of life (QOL), toxicity, and duration of current systemic agent post-SABR.

RESULTS

Between February 2017 and June 2021, 90 patients with 125 oligoprogressive metastases were enrolled across 8 Canadian institutions, with 59 patients randomized to SABR and 31 to SOC. Median age was 67 years (IQR: 61-73 years) and 39 (43%) were female. The most common primary sites were lung (44% of patients), genitourinary (23%) and breast (13%), with the most common oligo-progressive locations being lung (43%), bone (19%), lymph nodes (14%), and liver (13%). In the SABR arm, the most common fractionations were 35 Gy/5 (38% of lesions) and 50 Gy/5 (18%). Protocol adherence in the SOC arm was suboptimal: 3 patients (10%) withdrew immediately after randomization, and 7 additional patients (23%) received high-dose or ablative therapies. Median follow-up was 31 months. There was no difference in PFS between arms (median PFS 8.4 months in the SABR arm vs. 4.3 months in the SOC arm; however, the curves cross and 2-year PFS was 9% vs. 24% respectively, p = 0.91). Median OS was 31.2 months vs. 27.4 months, respectively (p = 0.22). Lesional control with SABR was 71% vs. 39% with SOC (p = 0.002). Median duration of post-randomization first-line systemic therapy was 10.3 months vs. 7.6 months, respectively (p = 0.71). Treatment was well-tolerated with 2 (3.4%) grade 3 treatment-related toxicities in the SABR arm and no grade 4/5 related events in either arm. QOL did not differ between arms.

CONCLUSION

Despite being a well-tolerated treatment providing superior lesional control, SABR for oligoprogression did not improve PFS or OS. Results may have been impacted by withdrawals and desire for ablative treatments on the SOC arm, and this lack of equipoise may make accrual to phase III trials difficult, although larger studies in select sub-populations are desired. (NCT02756793).

Complication Avoidance of Reconstruction Implant Radiation Therapy (CARIT): A Retrospective Case-Cohort Analysis

PURPOSE/OBJECTIVE(S)

Patients are increasingly offered implant-based reconstruction prior to radiotherapy. However, it is unclear if the radiation treatment technique itself impacts upon toxicity. We performed this study to compare outcomes following implant-based reconstruction amongst breast cancer patients treated with a standard radiotherapy technique that irradiates the entire chest wall versus a novel technique which uses a smaller clinical target volume (CTV) to spare the implant. Need for corrective surgery, capsular contracture, and cosmetic outcomes were evaluated, with the hypothesis that the novel technique would result in fewer adverse outcomes and less need for corrective surgery.

MATERIALS/METHODS

A retrospective case-cohort analysis of 57 patients who had post-mastectomy, implant-based reconstruction was conducted. Patients with invasive mammary carcinoma (IMC) or ductal carcinoma in-situ (DCIS) who were treated either with the novel radiotherapy technique (n = 26) or standard PMRT (n = 31) were included. Patient demographics such as age, BMI, TNM stage, implant size, hormone receptor status, and radiation course was collected. Primary endpoint was the need for corrective surgery within two years and cosmetic outcomes, measured using the Baker Classification Scale for capsular contracture and the Modified Harvard Harris Cosmetic Scale. Secondary endpoint was radiation-induced toxicity measured using the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE). Cosmesis and toxicity were evaluated at 3 months post-radiation, 1 year, and after 13 months. Unpaired t-tests were used to compare need for corrective surgery, cosmesis (Baker Grade 2 or higher and Harvard Harris "Good" or worse), and toxicity (NCI CTCAE Grade 2 or higher).

RESULTS

For the primary endpoint, need for corrective surgery, there was no significant difference between the novel and standard groups (two-sided p = 0.378, CI -0.38-0.14). The other primary endpoint of cosmesis, measured with the Baker scale and Harvard Harris, was also not significantly different (two-sided p = 0.147, CI -0.06-0.45), with the Harvard Harris cosmesis differences remaining insignificant across the 3 month, 1 year, and greater than 13 month periods (two-sided p = 0.854, 0.351, 0.468, respectively). The secondary endpoint, toxicity, was not significantly different between the novel and standard PMRT groups across 3 months and 1 year time periods (two-sided p = 0.328, 0.323, respectively). We will also be reporting the analysis for predictive factors related to toxicity, need for corrective surgery and cosmesis.

CONCLUSION

Compared with standard PMRT, the novel technique was not significantly different in rates of reoperation, toxicity and cosmetic outcomes. Better understanding the factors involved in PMRT outcomes for breast cancer patients with implant-based reconstructions will aid in the development of standardized approaches to treating the breast cancer patient population.

Phase III Study of Hypofractionated, Dose Escalation Radiotherapy vs. Conventional Pelvic Radiation Therapy followed by High Dose Rate Brachytherapy Boost for High Risk Adenocarcinoma of the Prostate (PCS VI): Acute Toxicity Results

PURPOSE/OBJECTIVE(S)

The low α\β ratio of 1.2-2 for prostate cancer (PCa) suggests high radiation-fraction sensitivity and predicts a therapeutic advantage of lager fraction size. We have recently shown (PCS5) that high risk prostate cancer patients can safely and effectively be treated with moderate hypofractionated radiation therapy (HF-RT). To date there has been no phase-III randomized clinical-trial comparing moderately HF-RT with EBRT and HDR boost (HDRB). We are reporting the acute safety of EBRT+HDRB compared to moderate HF-RT in this phase III Canadian trial.

MATERIALS/METHODS

From January 2015-June 2022, 308 high-risk localized PCa patients were randomized to receive either HF-RT or EBRT+HDRB. All patients received neo-adjuvant, concurrent, and long-term adjuvant androgen deprivation therapy (ADT). EBRT+HDRB consisted of 46 Gy in 2 Gy per fraction to the pelvis and a 15 Gy in one fraction HDR boost within 3 weeks of EBRT. HF-RT include concomitant dose escalation of 68 Gy in 2.72 Gy per fraction to the prostate, and 45 Gy in 1.8 Gy per fraction to the pelvic lymph-nodes.

RESULTS

Of the 308 patients, 148 received HF-RT and 144 EBRT+ HDRB. The remainder either withdrew from the study or were treated with standard (2 Gy per fraction) fractionation for technical reasons. In both intention to treat and as treated analysis, using log-Rank, there were more grade 1 or worse (G1+) acute GI and GU events and more G2+ acute GI events in the HF-RT than EBRT+HDRB. As treated analysis the acute G1+ and G2+ GI events were 92 vs 77 (60.1% vs. 53.5%; p < 0.017) and 21 vs 10 (13.7% vs. 6.9%; p = 0.052), respectively for HF-RT and EBRT + HDRB. Similarly, the G1+ acute GU events were 123 vs. 101 (80.4% vs.70.1%; p < 0.001) respectively for HF-RT and EBRT+HDRB. There were only four G3 GI and one G3 GU acute toxicities in both arms. No grade 4 toxicities were reported.

CONCLUSION

This is the first study of EBRT+HDRB compared to moderate HF dose escalated RT in high-risk prostate cancer patients treated with long-term ADT and pelvic RT. Our results demonstrate that both treatment approaches are well-tolerated and that EBRT+HDRB carries less G2+ GI and G1+ GU acute toxicities.

Treatment Modalities to Manage Hepatocellular Carcinoma Patients with Portal Vein Thrombus: A Systematic Review and Meta-Analysis

PURPOSE/OBJECTIVE(S)

Patients with hepatocellular carcinoma (HCC) and portal vein thrombosis (PVT) have poor outcomes and an effective treatment strategy has not been established. The aim of this review is to compare the effectiveness of available treatment options in preventing mortality.

MATERIALS/METHODS

A search was conducted in PubMed, EMBASE and Cochrane CENTRAL from 2007 to 2022. Articles were screened to identify studies of HCC patients with PVT that reported on all-cause mortality using radical intent treatments. Study quality was assessed using the Cochrane Risk of Bias in Non-Randomized Studies of Interventions tool (ROBINS-1). Mortality rates at prespecified timepoints between 6 and 24 months were extracted and summarized using a random-effects DerSimonian-Laird model. This review was registered a priori on PROSPERO (CRD42022290708).

RESULTS

The impact of radiotherapy (RT) on overall survival (OS) is similar to all other treatments including sorafenib. When comparing sorafenib to local modalities (Y90 and RT), the local treatments had a better OS (OR 2.20, 95% CI: 1.11 - 4.39), but this difference disappeared after 6-months. Indeed, within 6 months, Y90 provided the best OS. No significant differences were noticed from 12 to 24 months. Combination treatments appeared to provide a significant additional OS benefit with TACE+RT having an improved OS over TACE alone and RT alone, with the benefit extending to 24 months.

CONCLUSION

this analysis of HCC patients with PVT reports on six cohorts, with a total sample size of 2,356 patients. The addition of localized treatment to systemic treatment appears to improve survival. Combining TACE and RT was also better than either modality alone. Further investigations should be conducted, to further understand the role of localized treatments.

Validation of a survey instrument to measure the extent to which physician and dentist office environments discourage smoking

The health professional's office environment has been identified as one of the potential influences on smoking behaviour of patients. This study compared characteristics of office smoking policies and environments of 30 physicians and 30 dentists using both telephone survey and site visit. The site visit was considered the 'gold standard'. The sequence of interview presentation was randomly reversed for half the physicians and half the dentists to control for order effects. Kappa estimates and two-way Analysis of Variance were used on categorical and continuous variables, respectively. The results show there was a high agreement between the two modes of surveying. Physicians and dentists do not differ in level of agreement and in the consistency of responses obtained by telephone and site visit. We conclude that a telephone survey is a valid method to obtain smoking-related information from health professional offices.