Locoregional control and toxicity following high-dose hypofractionated and accelerated palliative radiotherapy regimens in breast cancer.

AIMS: For patients with locally advanced primary/recurrent breast cancer, radiotherapy is an effective treatment for locoregional control. 36 Gy in 6 Gy once-weekly fractions is a commonly used schedule, but there are no data comparing local control and toxicity between 36 Gy delivered once-weekly versus accelerated schedules of multiple 6 Gy fractions per week. This retrospective study compared local control rates and acute and late toxicity in patients undergoing 30-36 Gy in 6 Gy fractions over 6 weeks versus more accelerated schedules over 2-3 weeks for an unresected breast cancer. MATERIALS AND METHODS: Patients who received 30-36 Gy in 6 Gy fractions to an unresected breast cancer ± involved lymph nodes between December 2011 and August 2020 were identified. Patients were grouped into once-weekly versus accelerated fractionation schedules. Response rates, local control and toxicity data were analysed. RESULTS: In total, 109 patients were identified. The median follow-up duration was 46 months. Forty-seven patients (43%) received once-weekly fractions and 62 patients (57%) received accelerated fractionation schedules. There were no significant differences in baseline tumour characteristics between the groups. Eighty-seven per cent of patients had an objective (complete or partial) response (81% in the once-weekly group; 91% in the accelerated group). The median time to local progression was 23.5 months overall (95% confidence interval 17.8-29.2); 23.5 months (95% confidence interval 18.8-28.1) in the once-weekly group and 19.0 months (95% confidence interval 7.0-31.1) in the accelerated group (P = 0.99). Acute toxicity of any grade occurred in 75% of patients (76% in the once-weekly group; 74% in the accelerated group) and grade 3 toxicity occurred in 7% of patients (7% in the once-weekly group; 8% in the accelerated group). There were no associations between the groups and acute or late toxicity grade (P = 0.78 and P = 0.26, respectively), although one grade 4 late toxicity (skin radionecrosis) occurred in a patient who received five fractions a week and therefore this regimen is not recommended. Study limitations included a lack of statistical power analysis, the necessary grouping of all accelerated patients for analysis and a high rate of censored data. CONCLUSION: There were no apparent differences in response rate, time to local progression or toxicity between patients who received 30-36 Gy in 6 Gy fractions once-weekly compared with twice-weekly as palliative treatment for locally advanced breast cancer. This regimen appears to be a safe alternative and may be preferred by patients.

Evaluation of a method for grading late photographic change in breast appearance after radiotherapy for early breast cancer.

AIMS: Serial photographs have been collected prospectively to evaluate the effect of radiotherapy on normal tissues in the breast. The aim of this study was to compare two methods of scoring radiation-induced changes. MATERIALS AND METHODS: Five-year photographs of 400 patients randomised to receive either 42.9 or 39 Gy in 13 fractions to the whole breast after tumour excision of early breast cancer were compared with a post-surgery baseline and scored for change in breast appearance on a three-point graded scale. Two alternative methods of scoring using three observers were compared: (a) scores allocated independently, with independent resolution of discrepancies, and (b) scores allocated by consensus. RESULTS: Treatment effects estimated from the consensus and independent scores were very similar (odds ratio 1.89, 95% confidence interval 1.21-2.96 vs 2.28, 95% confidence interval 1.50-3.47, respectively). Agreement between the scores obtained from each method was reasonable, and the repeatability of the consensus method was good. CONCLUSIONS: The consensus method of scoring photographic change in breast appearance seems to be no less sensitive to randomised dose as the independent method of assessment, but is much quicker to administer. The consensus method has been used to score over 3000 sets of photographs in the National Cancer Research Institute Standardisation of Breast Radiotherapy trial.

Double-blind randomized phase II study of hyperbaric oxygen in patients with radiation-induced brachial plexopathy.

BACKGROUND: Radiation-induced brachial plexopathy (RIBP) is an untreatable complication of curative radiotherapy for early breast cancer, characterized by chronic neuropathic pain and limb paralysis. Hyperbaric oxygen (HBO2) therapy is known to promote healing of tissue rendered ischaemic by radiotherapy, but is untested in RIBP. METHODS: Thirty four eligible research volunteers suffering from RIBP were randomized to HBO2 or control group. The HBO2 group breathed 100% oxygen for 100 min in a multiplace hyperbaric chamber on 30 occasions over a period of 6 weeks. The control group accompanied the HBO2 group and breathed a gas mixture equivalent to breathing 100% oxygen at surface pressure. All volunteers and investigators, except the operators of the hyperbaric chamber and the trial statistician, were blind to treatment assignments. The warm sensory threshold, which measures the function of small sensory fibres, was selected as the primary endpoint. FINDINGS: Pre-treatment neurophysiological tests were grossly abnormal in the affected hand compared to the unaffected hand in both HBO2 and control groups, as expected, but no statistically significant differences were noted in either group at any time up to 12 months post-treatment. However, normalization of the warm sensory threshold in two of the HBO2 group was reliably recorded. Two cases with marked chronic arm lymphoedema reported major and persistent improvements in arm volume for at least 12 months after treatment with HBO2. IINTERPRETATION: There is no reliable evidence to support the hypothesis that HBO2 therapy slows or reverses RIBP in a substantial proportion of affected individuals, although improvements in warm sensory threshold offer some suggestion of therapeutic effect. Improvement in long-standing arm lymphoedema was not anticipated, and justifies further investigation.

Selective avoidance of lymphatic radiotherapy in the conservative management of women with early breast cancer.

BACKGROUND AND PURPOSE: Until recently, elective treatment of the lymphatic pathways in women with early invasive breast cancer was assumed to impact on quality of life rather than on overall survival. In a multidisciplinary breast clinic these considerations underpinned a policy of observation of the lymphatic pathways if axillary lymph nodes were not palpably enlarged and if recommendations for adjuvant systemic therapy did not depend on knowledge of pathological node status. This paper evaluates the long-term outcome of the observation policy in terms of lymphatic morbidity due to cancer recurrence. MATERIAL AND METHODS: Seven hundred and fifty-nine patients with operable breast cancer and suitable for breast conserving surgery were seen between January 1984 and December 1994. Of these, 291 (38.3%) were recommended a policy of observation to the lymphatic pathways. The case records of these patients were reviewed to record regional relapse patterns and morbidity. RESULTS: At a median follow up of 60 months, 32/291 (11%) patients suffered ipsilateral lymphatic relapse at some stage prior to death or last follow up, representing a 22% actuarial 10-year risk of lymphatic relapse. Metastases coincided with, or preceded, lymphatic relapse in 8/32 (25%) patients. Eighteen out of 32 (56%) patients suffered symptoms of lymphatic relapse prior to death or last follow up, despite subsequent surgery, radiotherapy and/or systemic therapies. The absolute risk of symptomatic ipsilateral lymphatic relapse in the observation group was 18/291 (6.2%), representing an actuarial 10-year risk of 17%. CONCLUSION: A policy of observation on the axilla with deferred treatment of lymphatic relapse has benefited 273/291 (94%) patients, but at the expense of cancer-related regional morbidity in 18 (6%) patients. We conclude that the cancer-related morbidity suffered by a minority of patients and the strengthening evidence of an overall survival benefit conferred by elective local-regional therapy favours a policy of elective treatment of the lymphatic pathways in the routine setting.

Lymphatic relapse in women with early breast cancer: a difficult management problem.

The aim of this study was to review the ability to control symptoms of regional lymphatic relapse in women with early breast cancer. A retrospective study was made of 759 consecutive women presenting with stage 1 or 2 breast cancer treated by breast conserving surgery and radiotherapy between June 1984 and December 1994, 291 (38.3%) of whom were managed by a policy of observation on the lymphatic pathways. Patterns of lymphatic relapse, relapse management and morbidity caused by recurrent malignancy were reviewed from the case notes. The overall rate of relapse in the ipsilateral axilla and/or supraclavicular fossa was 76/759 (10%) at any time prior to death or last follow-up. 34 of 65 patients who relapsed in the axilla did so despite prior axillary surgery and/or radiotherapy. 41 of 76 patients with regional recurrence presented with symptoms, including lymphoedema, arm pain or sensory motor changes. These symptoms were poorly controlled by palliative surgery, radiotherapy or systemic therapy in 23 cases, including 12 who progressed to arm paralysis. Symptomatic control of patients with regional lymphatic relapse can be very difficult, even in women under regular surveillance in a multidisciplinary breast cancer clinic.

Estrogen-mediated induction of rat prolactin gene transcription requires the formation of a chromatin loop between the distal enhancer and proximal promoter regions.

Rat PRL (rPRL) gene transcription is controlled by proteins that interact with two DNA elements located in the 5'-upstream regulatory region. These elements, the distal enhancer and the proximal promoter, are separated by nearly 1500 bp of DNA. Induction of rPRL transcription by the estrogen 17 beta-estradiol (E2) is conferred through the estrogen response element located in the distal enhancer. To activate transcription, the estrogen-estrogen receptor complex must "communicate" with RNA polymerase II located at the proximal promoter. Using a novel nuclear ligation assay, it is shown that estrogen treatment of rat pituitary GH3 cells stimulates the formation of chromatin loops between the distal enhancer and proximal promoter of the rPRL gene, juxtaposing these two transcriptional control regions. The formation of these chromatin loops was observed in both the endogenous rPRL gene and in a rPRL-Tn5 minichromosome. Induction of rPRL and rPRL-Tn5 expression by E2 was reduced by coincubation of cells with the antiestrogen 4-hydroxytamoxifen. Likewise, 4-hydroxytamoxifen was found to block the E2-induced formation of chromatin loops between the distal and proximal regions. Concurrent treatment with the synthetic glucocorticoid dexamethasone reduced the E2-induced transcription rate of the rPRL and rPRL-Tn5 gene to near basal levels. Similarly, dexamethasone treatment inhibited the ability of E2 to enhance the formation of the chromatin loops. These data suggest that the activation of rPRL gene transcription by E2 involves the stabilization of a chromatin loop that facilitates protein-protein interactions between transcription factors that are associated with the distal enhancer and the proximal promoter.