Variability in axillary lymph node delineation for breast cancer radiotherapy in presence of guidelines on a multi-institutional platform.

AIM: To quantify the variability between radiation oncologists (ROs) when outlining axillary nodes in breast cancer. MATERIAL AND METHODS: For each participating center, three ROs with different levels of expertise, i.e., junior (J), senior (S) and expert (E), contoured axillary nodal levels (L1, L2, L3 and L4) on the CT images of three different patients (P) of an increasing degree of anatomical complexity (from P1 to P2 to P3), according to contouring guidelines. Consensus contours were generated using the simultaneous truth and performance level estimation (STAPLE) method. RESULTS: Fifteen centers and 42 ROs participated. Overall, the median Dice similarity coefficient was 0.66. Statistically significant differences were observed according to the level of expertise (better agreement for J and E, worse for S); the axillary level (better agreement for L1 and L4, worse for L3); the patient (better agreement for P1, worse for P3). Statistically significant differences in contouring were found in 18% of the inter-center comparison. Less than a half of the centers could claim to have a good agreement between the internal ROs. CONCLUSIONS: The overall intra-institute and inter-institute agreement was moderate. Central lymph-node levels were the most critical and variability increased as the complexity of the patient's anatomy increased. These findings might have an effect on the interpretation of results from multicenter and even mono-institute studies.

Quality of life and cosmesis after breast cancer: whole breast radiotherapy vs partial breast high-dose-rate brachytherapy.

AIM AND BACKGROUND: Conservative surgery and radiotherapy for early breast cancer offers a better quality of life than mastectomy. As 80-85% of breast relapses develop close to the tumour bed, partial breast irradiation was developed to overcome drawbacks with standard radiotherapy. This study compares quality of life and cosmesis after partial breast multi-catheter high-dose rate interstitial brachytherapy or standard radiotherapy. METHODS: A questionnaire, exploring body image, fear of recurrence, satisfaction with treatment and cosmesis, was administered to 39 partial and 78 whole breast patients at a median of 20 and 80 months after radiotherapy. Patients' and physicians' cosmetic assessments were compared. RESULTS: Groups were well-matched, except for: a higher percentage of chemotherapy-treated patients in the whole breast group and a older median age and a higher percentage of infiltrating ductal carcinoma G1 in partial breast group. At first and second analysis no significant inter-group difference emerged on body image and fear of recurrence, while partial breast patients were more satisfied with cosmetic outcome and at first analysis with treatment. Comparing results from first and second analysis into each treatment group, body image was significantly better at the first analysis in both groups. Fear of recurrence was unchanged. No differences were found in cosmesis as assessed by patients. At first and second analyses physicians' assessment of cosmesis was significantly better in the partial breast group. CONCLUSIONS: Even at longer follow-up, quality of life is similar after partial or whole breast irradiation. Cosmesis is better after partial breast irradiation.

Outcome of a phase II prospective study on partial breast irradiation with interstitial multi-catheter high-dose-rate brachytherapy.

BACKGROUND AND PURPOSE: Partial breast irradiation (PBI) is an alternative to whole-breast irradiation after breast-conserving surgery in selected patients. Until the results of randomized phase III studies are available, phase II studies inform about PBI. We report the 5 year results of a phase II prospective study with PBI using interstitial multi-catheter high-dose-rate brachytherapy (ClinicalTrials.gov Identifier: NCT00499057). METHODS: Hundred patients received PBI (4 Gy, twice a day for 4 days, until 32 Gy). Inclusion criteria were: age ≥ 40years, infiltrating carcinoma without lobular histology, ductal in situ carcinoma, tumor size ≤ 2.5 cm, negative surgical margins and axillary lymph nodes. RESULTS: At a median follow-up of 60 months late toxicity occurred in 25 patients; the 5-year probability of freedom from late toxicity was 72.6% (95% CI: 63.7-81.7). Tamoxifen was the only significant risk factor for late toxicity. Cosmetic results, judged by physicians and patients, were good/excellent in 98 patients. Three local relapses (1 true, 2 elsewhere) and 1 regional relapse occurred. The 5-year probability of local or regional relapse-free survival was 97.7% (95% CI: 91.1-99.4) and 99.0% (95% CI: 92.9-99.8), respectively. CONCLUSION: PBI with interstitial multi-catheter brachytherapy is associated with low relapse and late toxicity rates.