Update on the Recommendations on Breast Cancer Screening by the Cancer Expert Working Group on Cancer Prevention and Screening

Breast cancer (BC) is the most common cancer among women in Hong Kong. The Food and Health Bureau commissioned The University of Hong Kong (HKU) to conduct the Hong Kong Breast Cancer Study (HKBCS) with the aim of identifying relevant risk factors for BC in Hong Kong and developing a locally validated BC risk assessment tool for Hong Kong Chinese women. After consideration of the most recent international and local scientific evidence including findings of the HKBCS, the Cancer Expert Working Group on Cancer Prevention and Screening (CEWG) has reviewed and updated its BC screening recommendations. Existing recommendations were preserved for women at high risk and slightly changed for women at moderate risk. The following major updates have been made concerning recommendations for other women in the general population: Women aged 44 to 69 with certain combinations of personalised risk factors (including presence of history of BC among first-degree relative, a prior diagnosis of benign breast disease, nulliparity and late age of first live birth, early age of menarche, high body mass index and physical inactivity) putting them at increased risk of BC are recommended to consider mammography screening every 2 years. They should discuss with their doctors on the potential benefits and harms before undergoing mammography screening. A risk assessment tool for local women (eg, one developed by HKU) is recommended to be used for estimating the risk of developing BC with regard to the personalised risk factors described above.

The Role of Radiotherapy in Epidermal Growth Factor Receptor Mutation-positive Patients with Oligoprogression: A Matched-cohort Analysis

AIMS

Almost all patients with epidermal growth factor receptor (EGFR) mutations will develop resistance to first-line EGFR tyrosine kinase inhibitors (TKIs). The management of oligoprogression on EGFR TKI is controversial. Irradiating progressing tumours may potentially eradicate the resistant clone and allow continuation of EGFR TKI, but the clinical data remain sparse. We aimed to assess the effect of radiotherapy on survival outcomes in patients with oligoprogression in a matched-cohort study.

MATERIALS AND METHODS

This was a retrospective matched-cohort study comparing patients with EGFR mutation-positive stage IV non-small cell lung cancer receiving radiotherapy versus chemotherapy for progression. Patients in the radiotherapy group received radiotherapy (mainly stereotactic ablative radiotherapy) for oligoprogression, whereas the chemotherapy group received only systemic chemotherapy upon progression. Key prognostic factors including gender, age, performance status, time to first progression and mutation subtypes were matched.

RESULTS

Twenty-five patients with oligoprogression (radiotherapy group) were identified, and a matched chemotherapy group with the same number of patients was generated. The median duration of follow-up was 24.3 and 34 months for the radiotherapy and chemotherapy groups, respectively. The median overall survival of the radiotherapy group was significantly longer than the chemotherapy group, 28.2 versus 14.7 months (P = 0.026). The median progression-free survival (PFS) was 7.0 and 4.1 months after radiotherapy and chemotherapy, respectively (P = 0.0017). The use of radiotherapy was an independent predictive factor of overall survival and PFS in multivariate analysis. Only one patient had ≥grade 3 toxicity after radiotherapy. The frequency of secondary T790M mutation and subsequent Osimertinib exposure were similar in both groups.

CONCLUSION

Radiotherapy may effectively extend EGFR TKI therapy for patients with oligoprogression on TKI. Improved PFS and overall survival were observed, although potential biases should not be overlooked. Further randomised studies are warranted.

Post-mastectomy Radiotherapy after Immediate Autologous Breast Reconstruction in Primary Treatment of Breast Cancers

AIM

To assess the clinical outcome of breast cancer patients with immediate autologous breast reconstruction and post-mastectomy radiotherapy (PMRT) as primary treatment.

MATERIALS AND METHODS

Twenty-five women with breast cancer treated with immediate autologous breast reconstruction and post-mastectomy radiotherapy as primary treatment between 1995 and 2001 in Pamela Youde Nethersole Eastern Hospital of Hong Kong were retrospectively studied. Radiation doses of 50 Gy (in 2 Gy daily fraction) were given to the reconstructed breasts, except one who was given 45 Gy (in 1.8 Gy daily fraction). Nine women (36%) were treated without bolus, whereas the other 16 women (64%) were treated with 0.5 cm thick bolus on alternate days. The main outcome measures include local control, treatment complications and cosmetic outcome.

RESULTS

Median follow-up was 3.7 years (range: 1.0-6.6 years). Two women (8%), who were treated without bolus, developed chest wall recurrences. The overall 5-year, actuarial, local failure-free rate and disease-specific survival rate were 89.8% and 77.9%, respectively. Apart from mild acute skin reactions, no significant acute radiotherapy side-effects were observed. No flap necrosis or flap loss was seen. The cosmesis of the reconstructed breasts were rated as good to excellent in 85% of the surviving patients. There was no observed adverse effect on cosmesis by adding bolus on alternate days.

CONCLUSION

PMRT after immediate autologous tissue-flap breast reconstruction is well tolerated and is not associated with increased incidence of complications. Adding 0.5 cm bolus on alternate days might improve local control without causing adverse cosmetic effect. The concern of adverse effects of radiotherapy should not exclude the choice of immediate breast reconstruction in suitable patients.