Purpose Clinical trials support adjuvant regional nodal irradiation (RNI) after breast-conserving surgery or mastectomy for patients with lymph node–positive breast cancer. Advanced treatment planning techniques (eg, intensity modulated radiation therapy [IMRT]) can reduce dose to organs at risk (OARs) in this situation. However, uncertainty persists about when IMRT is clinically indicated (vs 3-dimensional conformal radiation therapy [3DCRT]) for RNI. We hypothesized that an adaptive treatment planning algorithm (TPA) for IMRT adoption would allow OAR constraints for RNI to be met when 3DCRT could not without significantly changing toxicity and locoregional recurrence (LRR) patterns. Methods and Materials Since 2013, all RNI patients also underwent an adaptive TPA that began with 3DCRT and then changed to IMRT when OAR constraints (mean heart dose ≤500 cGy; ipsilateral lung V20 ≤35%) could not be met. Patients received 2 Gy/d to the prospectively contoured target volumes (including internal mammary nodes). We retrospectively evaluated the dosimetry and clinical outcomes of the treatment groups (IMRT vs 3DCRT). The primary endpoint was the cumulative incidence of LRR as the site of first recurrence, and we specifically address patterns of failure based on dose to the posterior supraclavicular nodal region (SCL-post). Results Two hundred forty patients (60% stage III; mean 4.0 + nodes) underwent an adaptive-TPA for RNI after mastectomy (74%) or breast-conserving surgery (26%), resulting in 168 patients treated with 3DCRT and 72 patients treated with IMRT. There were 7 LRRs (2 IMRT, 5 3DCRT) resulting in 4-year LRR of 2.8% for IMRT versus 1.8% for 3DCRT (P = .99). Three patients (2 IMRT, 1 3DCRT) had SCL nodal failures (1 in the SCL-post). Conclusions An adaptive TPA for use of IMRT when 3DCRT does not meet critical OAR constraints resulted in rare high-grade toxicity and no difference in failure patterns between patients treated with IMRT and 3DCRT. These data should provide reassurance that IMRT maintains the therapeutic ratio by preserving cancer control outcomes without excess toxicity when 3DCRT fails to meet OAR constraints.

Clinical Effectiveness of an Adaptive Treatment Planning Algorithm for Intensity Modulated Radiation Therapy Versus 3D Conformal Radiation Therapy for Node-Positive Breast Cancer Patients Undergoing Regional Nodal Irradiation/Postmastectomy Radiation Therapy.

Dosimetric parameters associated with radiation-induced esophagitis in breast cancer patients undergoing regional nodal irradiation.

AIM The aim of this study was to determine dosimetric factors, such as mean dose and oesophageal length, which may influence the incidence and severity of oesophagitis in breast cancer patients receiving radiotherapy to the supraclavicular nodes. METHODS This was a single-arm prospective observational study. Toxicity grading was undertaken twice weekly to determine the onset of grade 2 oesophagitis in consecutive patients prescribed IMRT to the breast or chest wall and supraclavicular fossa (SCF) nodes. Recorded variables included mean and maximum doses to the oesophagus, oesophageal length and pharynx length within the treatment area. Multivariate logistic regression and Fishers' exact test were used with a 0.05 significance level to compare the onset of grade 2 oesophagitis with these variables. RESULTS A total of 77 patients were included in the study. Twenty-four (31%) patients reported grade 2 oesophagitis. There was a higher incidence of grade 2 oesophagitis in patients receiving a mean oesophageal dose of ≥31 Gy compared to those receiving < 31 Gy (18/24 versus 6/24, respectively, P = 0.025). There was a significant difference in the onset of grade 2 toxicity in patients who had ≥ 1 cm of pharynx included in SCF fields compared with those with <1 cm (15/24 versus 9/24, respectively, P = 0.0116). The odds ratios for developing grade 2 oesophagitis were 3.2 (95% CI = 1.05-9.62, P = 0.04) for a mean dose of ≥31 Gy and 3.4 (95% CI = 1.19-9.5, P = 0.022) for ≥1 cm of pharynx in the SCF field. CONCLUSION By limiting the mean dose to the irradiated oesophagus to <31 Gy during the planning process and ensuring that <1 cm of pharynx is included in the radiation field, oesophageal toxicity may be minimised.

Radiation-induced oesophagitis in breast cancer: Factors influencing onset and severity for patients receiving supraclavicular nodal irradiation.

Purpose To investigate the incidence of skin acute reaction and its influencing factors in postoperative breast cancer radiotherapy patients. Methods One hundred and seventy three cases of breast cancer patients treated with postoperative radiotherapy were consecutively enrolled from June 1, 2016 to July 31, 2017 in our breast cancer center. Irradiation technology includes conformal intensity-modulated radiotherapy and a conventional two-dimensional one with conventional fraction. Any acute radiation dermatitis was recorded and the influencing factors were analyzed at the end of the radiation treatment. Results Radiotherapy-induced acute dermatitis in patients with breast-conserving surgery was relatively mild. Among the 173 patients, 33 cases had no obvious changes in the skin (grade 0); 121 cases had grade 1 skin reactions, manifested as local dark erythema and dry peeling; 29 cases had grade 2 skin reactions, characterized by edema, hyperemia, or erosion part; no grade 3 cases of skin reactions were observed. The incidence of grade 0, grade 1, and grade 2 reactions in all patients was 19.1%, 69.9%, and 11.0%, respectively. The severity of skin acute reaction is independent of the tumor sites, molecular subtypes, patients' age, and irradiation modalities, but it depends on the surgical types, fields treated, and planned total radiation. There is a trend favoring no chemotherapy over chemotherapy, though p-value is 0.074. Conclusion Skin acute reaction in postoperative radiotherapy breast cancer patients is generally common but mild, and there are quite a few patients who need interruption or cessation of the radiotherapy process. The patients need to be well informed and made aware that any skin reaction will likely be mild, especially for the breast-conserving patients.

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The incidence of postoperative radiotherapy-induced acute dermatitis in breast cancer and its influencing factors for Chinese women.

ORCID: 0000–0001-6019–7309. In the treatment of breast cancer, intensity-modulated radiation therapy (IMRT) reportedly reduces the high-dose irradiation of at-risk organs and decreases the frequency of adverse events (AEs). Comparisons with conventional radiotherapy have shown that IMRT is associated with lower frequencies of acute and late-onset AEs. Here, we extended a prospective, observational, single-center study of the safety of IMRT to a second investigating center. Patients scheduled for adjuvant IMRT after partial or total mastectomy were given a dose of 50 Gy (25 fractions of 2 Gy over 5 weeks), with a simultaneous integrated boost in patients having undergone conservative surgery. 300 patients were included in the study, and 288 were analyzed. The median follow-up period was 2.1 years. The 2-year disease-free survival rate [95% CI] was 93.4% [89.2–96.0%]. Most AEs were mild. The most common AEs were skin-related—mainly radiodermatitis [in 266 patients (92.4%)] and hyperpigmentation (in 178 (61.8%)). 35% and 6% of the patients presented with grade 2 acute skin and esophageal toxicity, respectively. Only 4 patients presented with a grade 3 event (radiodermatitis). Smoking (odds ratio) [95% CI] = 2.10 [1.14–3.87]; p = 0.017), no prior chemotherapy (0.52 [0.27–0.98]; p = 0.044), and D98% for subclavicular skin (1.030 [1.001–1.061]; p = 0.045) were associated with grade ≥ 2 acute AEs. In a univariate analysis, the mean dose, (p < 0.0001), D2% (p < 0.0001), D50% (p = 0.037), D95% (p = 0.0005), D98% (p = 0.0007), V30Gy (p < 0.0001), and V45Gy (p = 0.0001) were significantly associated with grade ≥ 1 acute esophageal AEs. In a multivariate analysis, D95% for the skin (p < 0.001), D98% for the subclavicular skin and low D95% for the internal mammary lymph nodes were associated with grade ≥ 1 medium-term AEs. The safety profile of adjuvant IMRT after partial or total mastectomy is influenced by dosimetric parameters.

Trial registration: ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT02281149","term_id":"NCT02281149"}}NCT02281149.

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Correlation between toxicity and dosimetric parameters for adjuvant intensity modulated radiation therapy of breast cancer: a prospective study.

Postmastectomy intensity modulation radiated therapy of chest wall and regional nodes: Retrospective analysis of the performance and complications up for 5 years.

Zhiwen Liang

Papers

Postmastectomy intensity modulation radiated therapy of chest wall and regional nodes: Retrospective analysis of the performance and complications up for 5 years.