Concomitant Boost Research Articles

Concomitant Boost With Six Fractions of Radiation a Week in Locally Advanced Head and Neck Cancer Patients: A Prospective Study.

Background and objective Radiation therapy plays a significant role in the radical treatment of locally advanced head and neck cancers. Studies have shown theradiobiological advantage of accelerated chemoradiation over conventional chemoradiation as it reduces the chances of accelerated repopulation and decreases overall treatment time. This study aimed to assess the response and toxicities of accelerated concomitant chemoradiation inlocally advanced head and neck cancer patients. Methods A total of 51 patients were enrolled and treated with accelerated concomitant chemoradiation, receiving one fraction of radiation per day, six fractions per week, with the sixth fraction as a boost on Saturdays, with weekly concurrent cisplatin at 40 mg/m2. Patients were followed up till six months after treatment completion. Radiological investigation was done to assess response according to Response Evaluation Criteria in Solid Tumors (RECIST) 1.128, and acute toxicities were assessed according to Radiation Therapy Oncology Group (RTOG) criteria. Results The median follow-up period was six months; 28 patients (62.22%) had a complete response and 17(37.78%) had a partial response at six months post-completion of the treatment. The maximum acute toxicities developed at the completion of treatment. Grade III and IV mucositis developed in 14 patients (31.11%) and grade III dermatitis developed in one patient (2.22%), without any grade IV dermatitis during the total duration of treatment. The toxicities were manageable, and most of them resolved after three months of treatment completion. Conclusions Accelerated concomitant chemoradiation with six fractions of radiation in a week led to a decrease in overall treatment time. Of note, 62.22% of patients had complete remission, with manageable acute mucositis and dermatitis, which resolved in 82% and 67%, respectivelywithin three months of treatment completion. However, further studies involving larger samples and longer follow-ups are needed for this regimen to be established as the standard of care in the future.

A Comparison of the Toxicities in Patients With Locally Advanced Head and Neck Cancers Treated With Concomitant Boost Radiotherapy Versus Conventional Chemoradiation.

To compare the objective and patient-reported toxicities of concomitant boost radiotherapy (CBRT) and concurrent chemoradiation (CRT) in patients with locally advanced head and neck cancers. In this prospective study, 46 patients with histologically proven stage III-IVA head and neck cancer were randomly assigned to receive either concurrent chemoradiation to a dose of 66 Gy in 33 fractions over 6.5 weeks with concurrent cisplatin (40 mg/m2 IV weekly; control arm) or accelerated radiotherapy with concomitant boost radiotherapy (study arm) to a dose of 67.5 Gy in 40 fractions in five weeks. Acute toxicity was evaluated using RTOG toxicity criteria. The assessment was done weekly after initiation of treatment, at the first follow-up (six weeks), and at three months. The four main patient-reported symptoms of pain, hoarseness of voice, dryness of mouth, and loss of taste were also compared between the two groups to assess patient quality of life during treatment. The mean treatment duration was 37 days in the CBRT arm and 49 days in the CRT arm. Treatment-related interruptions were less in the study group,17.3% in the study, and 27.2% in the control with insignificant P-value. Grade III laryngeal toxicity was significantly higher in the study group (P=0.029). Other acute grade I-III toxicities (pharyngeal, skin, mucositis, and salivary) were comparable in both CRT and CBRT arms. Grade IV toxicities were seen only in the CBRT arm but were resolved at the first follow-up. Haematological toxicities and renal toxicities were significantly higher in the CRT arm, with significant P-values of 0.0004 and 0.018, respectively. In patients with locally advanced head and neck cancer, concomitant boost radiotherapy is well tolerated with acceptable local toxicity and minimal systemic toxicity as compared to conventional chemoradiation. It is a feasible option for patients with locally advanced head and neck cancer not fit for concurrent chemoradiation.

CLO23-065: Dosimetric Comparison of Hypofractionation With Concomitant Boost Versus Sequential Boost Following Breast-Conserving Surgery in Early Stage Breast Cancer Patients

"CLO23-065: Dosimetric Comparison of Hypofractionation With Concomitant Boost Versus Sequential Boost Following Breast-Conserving Surgery in Early Stage Breast Cancer Patients" published on 31 Mar 2023 by National Comprehensive Cancer Network.

Physician Rated Cosmesis and Patient Reported Outcomes after Concomitant Boost (CB) vs. Sequential Boost (SB) for Adjuvant Treatment of Breast Cancer: A Prospective Randomized Study

<h3>Purpose/Objective(s)</h3> The aim of the current study was to compare toxicity, cosmesis and patient reported outcomes after sequential radiation therapy boost vs. concomitant boost in the adjuvant setting of breast cancer treatment. <h3>Materials/Methods</h3> One hundred and forty-five breast cancer patients who underwent breast conserving surgery and were candidates for tumor bed boost following whole breast irradiation (WBI) were randomized to receive either concomitant boost (CB) (n=71) or sequential boost (SB) (n=74). All patients received WBI to a total dose of 40.05 Gy/15 F/3 weeks. Patients in the SB arm received 10 Gy/5 F / 1 week to the boost volume following WBI. Patients in the CB arm received 7.95 Gy/15 F/3 weeks to the boost volume concomitant with the WBI. All treatments were carried out using 3D conformal radiation therapy. Physicians rated cosmesis prior to starting radiation and at 6 and 12 months after end of treatment. All patients filled a validated quality of Life questionnaire 12 months after end of treatment. <h3>Results</h3> Median follow-up 30 months (range, 18-48). G III or higher acute skin toxicity was observed in 12 (16.4%) patients in the SB arm and in 4 (6.3%) patients in the CB arm (p 0.042). GII or higher late skin toxicity developed in 4 (5.4%) patients in the SB arm and in 1 (1.4%) patient in the CB arm (p 0.18). GII subcutaneous fibrosis was observed in 3 (4%) patients in the SB arm and in none of the patients in the CB arm. Prior to radiation treatment, 50 (67.5%) patients had Excellent/good cosmesis in the SB arm vs. 47 (66.2%) patients in the CB arm (p 0.59). At 6 months after radiation, 44 (59.4%) patients had Excellent/good cosmesis in the SB arm vs. 40 (56.3%) patients in the CB arm (p 0.83). At 12 months after radiation, 50 (67.5%) patients in the SB arm had Excellent/good cosmesis vs 42 (59.2%) patients in the CB arm (p 0.57). twelve months after radiation, 50 (78.1%) patients in the SB arm reported very satisfied/satisfied with their cosmetic outcomes compared to 44 (72.1%) patients in the CB arm (p 0.43). <h3>Conclusion</h3> Concomitant boost radiation therapy is non-inferior to sequential boost in terms of late toxicity, cosmesis and patient satisfaction with slightly more favorable outcome in the acute toxicity and shorter overall treatment time.

Combining Step-and-Shoot Intensity Modulated Radiation Therapy Concomitant Boost to Tumor Bed and 3D Breast Field-in-Field Plans for Hypofractionated Breast Radiotherapy

<h3>Purpose/Objective(s)</h3> To investigate the efficacy and safety of step-and-shoot intensity modulated radiation therapy (IMRT) concomitant boost (CB) to tumor bed (TB) combined with 3D breast field-in-field (FIF) plans for hypofractionated breast radiotherapy. <h3>Materials/Methods</h3> We initiated prospective cohort study since January, 2020. The patients with early-stage breast cancer or breast ductal carcinoma in situ who received breast-conserving surgery underwent sixteen-fraction treatment. All received prescribed dose of 40 Gy 3D FIF plans to breast, CB with 8 Gy to TB by IMRT. We applied the identical contours and PTV coverage to compare the original plans with the re-plans using conventional fractions of breast FIF followed by en face electron beams to TB on the same patients. Plan quality including maximum dose, RTOG conformal index (CI) and homogeneity index (HI) of PTV_TB, mean dose and volumes irradiated to doses of 5 Gy (V₅) of heart and V₂₀ of ipsilateral lung, in addition to acute toxicity and any recurrence were evaluated. Lyman normal tissue complication probability (NTCP) model for moderate to severe breast fibrosis established by Cambridge and EORTC trials was also calculated. Paired sample t-test and Wilcoxon signed-rank test were used. <h3>Results</h3> Thirty patients with sixty treatment plans were reviewed. The majority (19/30) were pathological prognostic stage I breast cancer and half of the patients were left-sided diseases. No patient experienced more than grade 2 acute toxicity. No recurrence was observed during the follow-up. Mean HI (D₂-D₉₈/D_p × 100; where D₂ = minimum dose to the 2% of the target volume, D₉₈ = minimum dose to the 98% of the target volume, and D_p = prescribed dose) of PTV_TB is 9.4 vs. 18.5 (<i>P</i> < .05). Maximum dose divided by reference dose was also lower in the CB group by 2.9% (<i>P</i> < .05). Mean CI is 1.45 in the CB group compared to 1.63 in the conventional fraction plans (<i>P</i> = .07). In terms of EQD2, mean dose and V₅ of heart for left-sided breast cancer are similar (<i>P</i> = .12 and 0.10). Besides, mean dose and V₂₀ of ipsilateral lung are comparable (<i>P</i> = .26 and 0.43). NTCP for breast fibrosis were all lower in the CB group (Mean: 20.02% vs. 22.13%; <i>P</i> < .05). <h3>Conclusion</h3> Hypofractionated breast radiotherapy combing 3D FIF plans and IMRT CB to TB decreased breast moderate to severe fibrosis by Lyman NTCP model and improved homogenous dose distributions without excessive dose to normal tissue, when compared to conventional fractions using FIF and electron beams. It may reduce the toxicity, and is also labor-saving for patients, radiation oncologists and staff.

Randomized, Multicenter, Phase 3 Study of Accelerated Fraction Radiation Therapy With Concomitant Boost to the Gross Tumor Volume Compared With Conventional Fractionation in Concurrent Chemoradiation in Patients With Unresectable Stage III Non-Small Cell Lung Cancer: The Korean Radiation Oncology Group 09-03 Trial

We designed the Korean Radiation Oncology Group 09-03 phase III clinical trial to compare accelerated hypofractionated radiation therapy (RT) using a concomitant boost to the gross tumor volume (GTV) with conventionally fractionated 60-Gy RT in patients with stage III unresectable non-small cell lung cancer (NSCLC). A conventionally fractionated RT group (arm 1; 124 patients) received a 2-Gy daily dose to a total cumulative dose of 44 Gy to the planning target volume (PTV) in 22 fractions and 60 Gy to the GTV in 30 fractions over 6 weeks. A hypofractionated RT group (arm 2; 142 patients) received a 1.8-Gy daily dose to the PTV with a synchronous boost of 0.6 Gy to the GTV, for total cumulative doses of 45 Gy to the PTV and 60 Gy to the GTV in 25 fractions over 5 weeks. All patients received concurrent weekly chemotherapy consisting of paclitaxel and cisplatin. The objective response rate of all patients was 86.5% (arm 1, 84.6%; arm 2, 88.1%; P=.612). The median overall survival was 26 months (arm 1, 26 months; arm 2, 27 months; P=.508). The median progression-free survival was 11 months (arm 1, 10 months; arm 2, 13 months; P=.295). The local tumor control rates at 2 and 5 years were 58.3% and 50.7%, respectively (arm 1, 62.4% and 51.0%, respectively; arm 2, 54.0% and 48.6%, respectively; P=.615). There were no significant between-group differences in the cumulative incidence of grade ≥3 radiation pneumonitis (P=.134) or radiation esophagitis (P=.539). This clinical trial did not confirm the superiority of accelerated 2.4-Gy hypofractionated RT compared with conventional 2-Gy fractionation in patients with unresectable stage III NSCLC undergoing concurrent chemoradiation therapy.

Hypofractionation and Concomitant Boost in Ductal Carcinoma In Situ (DCIS): Analysis of a Prospective Case Series with Long-Term Follow-Up.

We previously reported on a cohort of breast cancer patients affected with ductal carcinoma in situ (DCIS) that were treated with breast conservative surgery and hypofractionated whole-breast radiotherapy with a concomitant boost to the lumpectomy cavity. We now report on the long-term results of the oncological and toxicity outcomes, at a median follow-up of 11.2 years. We also include an analysis of the predictive factors for local recurrence (LR). Eighty-two patients with long-term observation were considered for this report. All received hypofractionated post-operative radiotherapy with a concomitant boost (45 Gy/20 fractions to the whole breast and 50 Gy/20 fractions to the lumpectomy cavity). We report on LC rates at 5 and 10 years, overall survival (OS), and breast-cancer-specific survival (BCSS), employing the Kaplan–Meier method. Cox proportional regression analysis was used to determine the role of selected clinical parameters on the risk of local recurrence, by the univariate and multivariate models. After a median follow-up of 11.2 years (range 5–15 years), 9 pts (11%) developed LR. The LR rates at 5 years and 10 years were 2.4% and 8.2%, respectively. The 5- and 10-year overall survival rates were 98.8% and 91.6%, respectively. The 5- and 10-year breast-cancer-specific survival rates were 100.0% and 99.0%. Late skin and subcutaneous toxicities were generally mild, and cosmetic results were good–excellent for most patients. For the univariate regression analysis, ER positive status (HR; 95% CI, p = 0.021), PgR positive status (HR; 95% CI, p = 0.012), and the aggregate data of positive hormonal status (HR; 95% CI, p = 0.021) were inversely correlated to LR risk. Conversely, a high tumor grade (G3) was directly correlated with the risk of LR (HR; 95% CI, p = 0.048). For the multivariate regression analysis, a high tumor grade (G3) confirmed its negative impact on LR (HR 0.40; 95% CI 0.19–0.75, p = 0.047). Our long-term data demonstrate hypofractionated whole-breast radiotherapy with a concomitant boost to be feasable, effective, and tolerable. Our experience suggests positive hormonal status to be protective with respect to LR risk. A high tumor grade is a risk factor for LR.

Mature Outcomes of 61.2 Gy Concomitant Boost (CB) Thoracic Radiotherapy (TRT) in Limited Stage Small Cell Lung Cancer (LSCLC): CALGB 30610 (Alliance) / RTOG 0538

<h3>Purpose/Objective(s)</h3> We report mature outcomes of LSCLC patients randomized to the 61.2 Gy CB TRT arm of CALGB 30610/RTOG 0538. The study initially included 2 experimental arms, 61.2 Gy CB TRT over 5 weeks and 70 Gy daily (QD) over 7 weeks, both with higher predicted biologic efficacy than standard 45 Gy twice-daily (BID)TRT. The CB arm was discontinued after planned early interim analysis comparing toxicity in the experimental arms, but the study provides the largest prospective dataset assessing 61.2 Gy CB TRT in LSCLC <h3>Materials/Methods</h3> Eligible patients had LSCLC with regional lymph node involvement, excluding contralateral hilar and supraclavicular nodes, and ECOG PS 0-2. TRT began with either the first or 2^nd (of 4 total) cycle of cisplatin-based chemotherapy, and prophylactic cranial radiotherapy was recommended in cases of complete (or near complete) response. In the initial phase of the trial, patients were randomized with a 1:1:1 allocation to 45 Gy BID, 70 Gy QD and 61.2 Gy CB TRT. A decision to drop an experimental arm was mandated after toxicity data was available for approximately 70 patients in each cohort. Although toxicity was similar in both experimental arms, a decision was made to discontinue the 61.2 Gy cohort after discussion with the DSMB. <h3>Results</h3> From March 2008 until March 2013 (when the cohort was discontinued), 93 patients were assigned to receive 61.2 Gy CB TRT. The median age was 62 years (range 41 to 77), the majority of patients were Caucasian (86%), male (51%), ECOG PS 0-1 (95%). Most patients started TRT with the first chemotherapy cycle (65%) and had 3D planning (63%). After median follow up of 7 years for surviving patients, median overall survival (OS) and progression free survival were 32.3 months (95% CI: 21.1-44.8) and 15.6 months (95% CI: 10.0-27.5), respectively. Two-year OS was 57% (95% CI: 0.47-0.68), with 28% OS (95% CI: 0.2-0.4) at 5 years. Rates of grade 3 and 4 hematologic adverse events (AEs) were 20.5% and 59.1%, with 40.9% and 25% Grade 3 and 4 non-hematologic AEs. Grade 3+ dysphagia and dyspnea were 16% and 7%, respectively. There were 4 Grade 5 AEs, including one patient with febrile neutropenia. <h3>Conclusion</h3> Outcomes are similar to the contemporaneous CONVERT trial, and compare favorably to the prior phase II trial examining 61.2 Gy CB TRT (RTOG 0239) in LSCLC, despite the allowance of early stage (N0) disease in those studies. The improvement in OS compared with RTOG 0239 is likely attributed to improved staging and advances in radiotherapy planning and delivery, though additional factors may have contributed. Support: U10CA180821, U10CA180882; U10CA180868 (NRG), U10CA180888 (SWOG); https://acknowledgments.alliancefound.org Clinicaltrials.gov Id: NCT00632853

Long-term results of hypofractionation with concomitant boost in patients with early breast cancer: A prospective study

To report the long-term local control and survival of patients with early breast cancer who had hypofractionated whole breast irradiation with concomitant boost (Hypo-CB). Between October 2009 and June 2010, 73 patients with early breast cancer (T1-3N0-1M0) who underwent breast conserving surgery were enrolled into the study. Thirty-six of these participants received 50 Gy of conventional irradiation in 25 fractions over 5 weeks to the whole breast with a sequential boost to the tumor bed with 10-16 Gy in 5-8 fractions (Conv-SEQ). The other 37 participants received a hypofractionated dose of 43.2 Gy in 16 fractions with an additional daily concomitant boost (CB) of 0.6 Gy over 3 weeks (Hypo-CB). At a median follow-up time of 123 months, ipsilateral local recurrence (ILR) was found in 3 participants, 1 of whom was in the hypofractionated group. All 3 ILR were true local recurrence (TR). There were no significant differences in the 10-year disease free survival (DFS) and 10-year overall survival rates (OS) between the conventional and hypofractionated groups (93.9% vs. 94.4%, p = 0.96 and 91.9% vs. 91.6%, p = 0.792, respectively). This study showed that the effectiveness, DFS and OS were comparable between hypofractionated whole breast irradiation with a CB and the conventional irradiation with a sequential boost.

Phase 3 comparison of high-dose once-daily (QD) thoracic radiotherapy (TRT) with standard twice-daily (BID) TRT in limited stage small cell lung cancer (LSCLC): CALGB 30610 (Alliance)/RTOG 0538.

8505 Background: Although level 1 evidence is lacking, the majority of patients (pts) with LSCLC are treated with a high dose QD TRT regimen in clinical practice. CALGB 30610/RTOG 0538 was designed to determine if administering high dose TRT would improve overall survival (OS), compared with standard 45 Gy BID TRT, in LSCLC pts treated with chemoradiotherapy. Methods: Eligible pts had LSCLC, ECOG performance status (PS) 0-2 and regional lymph node involvement excluding contralateral hilar or supraclavicular nodes. This phase 3 trial was conducted in 2 stages. In the first stage, pts were randomized 1:1:1 to 45 Gy BID over 3 weeks, 70 Gy QD over 7 weeks, or 61.2 Gy concomitant boost (CB) over 5 weeks. For the second stage, the study planned discontinuation of one high dose arm based on interim toxicity analysis with patients then randomized 1:1 in the two remaining arms. TRT was given starting with either the 1st or 2nd (of 4 total) chemotherapy cycles. The primary endpoint was OS measured from date of randomization. Results: The trial opened 03/15/2008 and closed 12/01/2019 upon completing accrual, with the CB arm discontinued 3/11/2013 after interim analysis. This analysis includes 638 pts randomized to 45 Gy BID TRT (n = 313) or 70 Gy QD TRT (n = 325). Median age was 63 years (range 37-81), the majority of pts were Caucasian (86%), female (52%), and with ECOG PS 0-1 (95%). After median follow-up of 2.84 years (IQR:1.35 -5.61) for surviving pts, QD compared to BID did not result in a significant difference in OS (HR 0.94, 95% CI: 0.76-1.2, p = 0.9). Median, 2- and 4-year OS for QD were 30.5 months (95% CI: 24.4-39.6), 56% (95% CI: 0.51-0.62), and 39% (95% CI: 0.33-0.45), and for BID 28.7 months (95% CI: 26.2-35.5), 59% (95% CI: 0.53-0.65), and 35% (95% CI: 0.29-0.42). QD also did not result in a significant difference in PFS (HR 0.96, 95% CI: 0.78-1.18, p = 0.94). Most grade 3+ hematologic and non-hematologic adverse events (AEs) were similar between cohorts. Rates of grade 3+ febrile neutropenia, dyspnea, esophageal pain and dysphagia for QD were 12.6%,7%, 11.6% and 11.3%, and for BID 13.6%, 4%, 11.2 % and 9.5%. Grade 5 AEs were reported in 3.7% and 1.7% of the QD and BID cohorts, respectively. Results will be updated at presentation. Conclusions: High dose QD TRT to 70 Gy did not significantly improve OS compared with standard 45 Gy BID TRT. Nevertheless, favorable outcomes on the QD arm provide the most robust evidence available supporting high dose once-daily TRT as an acceptable option in LSCLC. Outcomes from this study, the largest conducted in LSCLC to date, will help guide TRT decisions for this patient population. Support: U10CA180821, U10CA180882; Clinical trial information: NCT00632853.

Short Communication: Interim toxicity analysis for patients with limited stage small cell lung cancer (LSCLC) treated on CALGB 30610 (Alliance) / RTOG 0538

IntroductionThe CALGB 30610/RTOG 0538 randomized trial was designed to test whether high-dose thoracic radiotherapy (TRT) would improve survival compared with 45 Gy twice-daily (BID) TRT in limited stage small cell lung cancer (LSCLC). Two piloted experimental TRT regimens were of interest to study, 70 Gy daily (QD) and 61.2 Gy concomitant boost (CB). Driven by concerns about adequate patient accrual, a study design was employed that eliminated one experimental TRT arm based on early interim toxicity and tolerability, with the study then continuing as a traditional 2-arm phase III study. MethodsPatients with LSCLC were assigned to receive four cycles of cisplatin and etoposide chemotherapy with one of 3 TRT regimens starting with either the first or second cycle of chemotherapy. The interim endpoint was the cumulative highest toxicity calculated from a scoring system based on treatment-related grade 3 and higher toxicity and the ability to complete therapy in the experimental arms. ResultsThe final interim analysis was performed after 70 patients accrued to each experimental cohort, and a difference in treatment related toxicity scoring was not found (p = 0.739). Severe esophageal toxicity was comparable in both cohorts. Pulmonary toxicity was low overall, though 4 patients (5.7 %) on the 61.2 Gy arm developed grade 4 dyspnea, which was not observed in the 70 Gy arm. A protocol mandated decision was made to discontinue the 61.2 Gy arm following review of toxicity with the Data and Safety Monitoring Board. ConclusionA randomized trial design using a planned early interim toxicity analysis to discriminate between experimental treatment arms is feasible in a phase III setting. Refinement of the design could increase the likelihood of detecting clinically meaningful differences in toxicity in future studies.

Neoadjuvant Chemotherapy and Concomitant Boost Radiotherapy in the Treatment of Locally Advanced Rectal Cancer

Aims: This study aimed to examine the efficacy and toxicities of concomitant boost three-dimensional conformal radiotherapy along with multidrug chemotherapy (capecitabine and oxaliplatin) in neoadjuvant course for locally advanced rectal cancer (LARC).&#x0D; Study Design: A phase II interventional nonrandomized study.&#x0D; Place and Duration of Study: This Study was conducted at Clinical Oncology and nuclear medicine department of Mansoura University Hospitals (Egypt) between November 2016 and October 2019.&#x0D; Methodology: Thirty patients (18 women, 12 men; age range 18-75 years) with (cT3-T4 and/or cN+) histologically confirmed rectal adenocarcinoma located within 12 cm of the anal verge were included in this study. Patients received three-dimensional conformal radiotherapy (3DCRT) to the pelvis of 45 Gy and a concomitant boost of 10 Gy to the primary tumor in 25 fractions, and concurrent with oxaliplatin (50 mg/m2 d1 weekly) and capecitabine (625 mg/m2 bid d1–5 weekly). Radical surgery was scheduled six to eight weeks after chemoradiation. Acute toxicities were recorded according to Common Terminology Criteria for Adverse Event (CTCAE) v5.0. Potential prognostic factors were evaluated using a binomial logistic regression. Survival curves were estimated using the Kaplan-Meier method and compared with Log-rank test.&#x0D; Results: All patients received chemoradiation. Twenty-seven patients underwent surgical resection. Twenty-five patients underwent sphincter-sparing surgery (92.6%) and nine patients (33.3%) achieved pathological complete response (pCR). The incidences of grade III neutropenia, diarrhea, and radiation dermatitis were 6.7%, 6.7%, 3.3% respectively. The three-year local recurrence (LR), disease-free survival (DFS) and overall survival (OS) rates were 7.4%, 63% and 74.1%, respectively. We found pre-surgical negative nodal status to be significantly associated with pCR (p=0.009). The pathological nodal stage was an independent prognostic factor to DFS.&#x0D; Conclusion: The combination of oxaliplatin, capecitabine, and dose escalation using concomitant boost 3DCRT is safely administrated in patients with locally advanced rectal adenocarcinoma and it offers high pCR and sphincter preservation rate.

Accelerated Fractionation With Concomitant Boost vs. Conventional Radio-chemotherapy for Definitive Treatment of Locally Advanced Squamous Cell Carcinoma of the Head-and-Neck (SCCHN).

Patients with unresectable head-and-neck cancer (SCCHN) unable to tolerate radiochemotherapy may receive unconventionally fractionated radiotherapy. This retrospective study compared both treatments. Eight patients unsuitable for chemotherapy were assigned to accelerated fractionation with concomitant boost (AF-CB, 69.6 Gy/39 fractions) over 5.5 weeks (group A) and 72 patients to cisplatin-based radiochemotherapy (70 Gy/35 fractions) over 7 weeks (group B). Groups were matched (cancer site, gender, age, performance score, T-/N-stage, histologic grade) and compared for loco-regional control (LRC), metastases-free survival (MFS), overall survival (OS) and toxicities. LRC, MFS, OS and radiation-related toxicities were not significantly different between groups A and B. Improved outcomes were associated with favorable cancer site, better performance score and T3-stage. In group B, toxicity led to reduction/discontinuation of chemotherapy in 38.9% and interruptions of radiotherapy >7 days in 19.3% of patients. AF-CB appeared a reasonable alternative for patients who cannot safely receive radio-chemotherapy for unresectable SCCHN.

Comparison of Conventional Fractionation and Accelerated Fractionation With Concomitant Boost for Radiotherapy of Non-metastatic Stage IV Head-and-Neck Cancer.

Some patients with unresectable or incompletely resected head-and-neck cancer (SCCHN) cannot tolerate radiochemotherapy. Alternatives are needed that are more effective than conventional radiotherapy alone. This retrospective study investigated patients irradiated for non-metastatic stage IV SCCHN who could not receive concurrent chemotherapy. Eight patients received accelerated radiotherapy with concomitant boost (group A) and 31 patients conventionally fractionated radiotherapy (group B). Groups were matched for tumor site, gender, age, performance score and histologic grade. Two-year PFS-rates were 63% in group A vs. 41% in group B, and median PFS-times were 36 vs. 10 months (p=0.48). Two-year OS-rates were 88% vs. 37%, and median OS-times were 44 vs. 14 months (p=0.19). Grade ≥2 radiation dermatitis was significantly (p=0.040) more common in group B; other toxicities were similar. Accelerated fractionation with concomitant boost appeared superior to conventional fractionation and can be considered for patients with stage IV SCCHN not suitable for radiochemotherapy. Larger studies are needed to confirm these findings.

Intensity-Modulated Radiotherapy with Concomitant Boost After Breast Conserving Surgery: A Phase I-II Trial.

PurposeA concomitant boost (CB) in patients treated with postoperative radiotherapy after conservative surgery of invasive breast cancer (BC) has been suggested for treatment time reduction and therapy intensification. The aim of this analysis was to assess long-term tolerability of a CB in patients treated with postoperative intensity Modulated Accelerated RAdiotherapy (MARA).Patients and MethodsIn this phase I–II trial, 321 patients with intermediate-high risk BC (pT1-4 with at least one of the following characteristics: pre or perimenopausal status, pN2-3, positive or close margins) were enrolled. Patients were treated with forward-planned intensity modulated radiotherapy (IMRT) and CB. A total dose of 50 Gy (2 Gy/fraction) and 60 Gy (2.4 Gy/fraction) was prescribed to the whole breast and the tumor bed, respectively. The potential impact of hypertension, diabetes, smoking habit, alcohol consumption, chemotherapy, and hormone therapy on both skin and subcutaneous late toxicity-free survival (LTFS) was evaluated. Survival curves were calculated using the Kaplan–Meier method.ResultsMedian follow-up was 52 months (range: 3–115). Regional node irradiation, adjuvant chemotherapy and hormonal therapy were prescribed to 29.3%, 65.4% and 81.0% of patients, respectively. Five-year G2 and G3 skin LTFS were 95.6% and 100.0%, respectively. Five-year G2 and G3 subcutaneous LTFS were 80.0% and 98.6%, respectively. Only diabetes showed a significant correlation with worse G3 subcutaneous LTFS (p: 0.024). Five-year loco-regional control, metastasis-free survival, disease-free survival, and overall survival were 98.0%, 91.8%, 89.7% and 96.3%, respectively.ConclusionIMRT combined with CB was associated with a low risk of > G2 late toxicities (0.0% and 1.4% for skin and subcutaneous tissue, respectively). The cumulative actuarial incidence of local recurrences was 2.0% despite the exclusion of low-risk patients. Our results suggest that CB is safe and effective in patients with intermediate-high risk BC.Trial RegistrationClinicalTrials.gov: NCT03471741.

PO-0972: Hypofractionation With Concomitant Boost In Breast Cancer: Efficacy And Toxicity.

PO-0972: Hypofractionation With Concomitant Boost In Breast Cancer: Efficacy And Toxicity.

Dose Escalated Concurrent Concomitant Boost to Gross Adenopathy in Gynecologic Malignancies

Dose Escalated Concurrent Concomitant Boost to Gross Adenopathy in Gynecologic Malignancies

Three-Dimensional Conformal Radiotherapy with Concomitant Boost and Weekly Cisplatin in Muscle-Invasive Transitional Cell Bladder Carcinoma

Abstract Background: Local control of MIBC by bladder-sparing approach is unsatisfactory. In order to improve the effectiveness of radiotherapy, we have designed a protocol that combines TURB with a non-conventionally fractionated radiotherapy “concomitant boost. Aim of Study: To evaluate the response rate and toxicity criteria in patients with transitional cell bladder cancer treated with maximum Transurethral Resection (TUR), followed by 3-D conformal radiotherapy with a concomitant boost and weekly cisplatin with shortening of overall treatment time. Patients and Methods: Between July 2017 to June 2018, 20 patients with a T2-T3 N0M0 transitional cell carcinoma of the bladder underwent transurethral resection of bladder tumor as much as safely possible (maximum TURBT). They received radiotherapy delivered in short overall treatment time with a concomitant boost technique. With this technique, a dose of 40Gy in 2-Gy fractions was administered to the small pelvis with a concomitant boost limited to the bladder tumor area plus a margin of 15Gy in fractions of 0.75Gy. The total tumor dose was 55Gy in 20 fractions in 4 weeks. Weekly Cisplatin (30mg/m2) was administered weekly concurrently with radiotherapy. Cisplatin was interrupted in case of hema-tological or renal toxicity. The National Cancer Institute Common Toxicity Criteria, version 5, scale was used to assess the chemotherapy and acute radiation toxicity {Common Terminology Criteria for Adverse Events (CTCAE), Version 5.0, November 2017}. We assessed late toxicity using The Radiation Therapy Oncology Group/The European Organiza-tion for Research and Treatment of Cancer (RTOG/EORTC) Late Radiation Morbidity Scoring Scheme. Results: The feasibility of the treatment was good. Severe acute toxicity >!G3 was observed in two patients (10%). Severe late toxicity >!G3 was observed in one patient (5%). Fourteen patients (70%) showed a complete and three (15 %) a partial remission after treatment. Conclusion: In external radiotherapy for muscle-invasive bladder cancer a concomitant boost technique coupling a partial bladder boost with shortening of the overall treatment time provides a high probability of local control with acceptable toxicity.

A Prospective Study to Compare Concomitant Boost Radiotherapy and Conventional Radiotherapy in Oral Cavity Cancer

A Prospective Study to Compare Concomitant Boost Radiotherapy and Conventional Radiotherapy in Oral Cavity Cancer

A Prospective Study to Compare Concomitant Boost Radiotherapy and Conventional Radiotherapy in Oral Cavity Cancer

A Prospective Study to Compare Concomitant Boost Radiotherapy and Conventional Radiotherapy in Oral Cavity Cancer