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A girl who had radiotherapy to the chest carries a risk of breast cancer by age 50 of about 30 per cent. It is not only about dose: a low dose to the whole lung gave a higher standardised incidence than a high dose to a smaller field, because volume matters. Surveillance is recommended from early adulthood, decades before ordinary screening starts.
Among 1,230 female survivors of childhood cancer treated with chest irradiation in the Childhood Cancer Survivor Study, the cumulative incidence of breast cancer by age 50 was 30 per cent (95 per cent confidence interval 25 to 34), and 35 per cent among survivors of Hodgkin lymphoma (29 to 40). The comparison that changed practice was between fields. Survivors treated with lower delivered doses to a large volume, whole-lung irradiation at a median 14 gray (range 2 to 20), had a standardised incidence ratio of 43.6 (27.2 to 70.3), higher than survivors given high doses to the mantle field at a median 40 gray, whose standardised incidence ratio was 24.2 (20.7 to 28.3). The authors' conclusion was that whole-lung irradiation carries "a greater risk of breast cancer than previously recognized, demonstrating the importance of radiation volume". The outcome is not benign either: breast cancer-specific mortality was 12 per cent at five years (8 to 18) and 19 per cent at ten (13 to 25).
The surveillance recommendation is harmonised. The International Guideline Harmonization Group's 2013 recommendations cover female survivors given radiation to fields that include breast tissue before age 30, with recommendations graded by the strength of the underlying evidence, and the Children's Oncology Group guidelines carry the same requirement by exposure. In practice this means annual imaging beginning in early adulthood, typically with magnetic resonance imaging alongside or instead of mammography, in a woman far younger than any population screening programme would invite. It also means that whether a survivor is offered it depends entirely on whether anybody knows she had chest radiotherapy, which is the argument for a treatment summary the survivor holds.
Two honest qualifications. First, the cohort describes women treated before 1987 with techniques and doses that are no longer standard; the risk for a girl treated today with modern fields, lower doses or protons should be lower, though by how much is not yet measurable because the latency has not elapsed. Second, there is no randomised trial showing that screening these women reduces their breast cancer mortality. The recommendation rests on the magnitude of the risk, the youth of the women, the evidence that magnetic resonance imaging detects early disease in high-risk groups and the mortality figures above. OnCo states that rather than implying a trial exists.
What comes back, and when: this record is about detection rather than recovery. The one thing that is entirely within reach is the information: a woman who knows she had chest radiotherapy, and at what age, can ask for the surveillance. A woman who does not will be told she is too young.
Breast tissue is at its most radiosensitive during the proliferation of puberty, so irradiation of the chest before age 30 and especially during adolescence produces a lasting excess of breast cancer after a latency of eight years or more. Risk scales with the volume of breast tissue in the field as well as with dose, which is why a low-dose whole-lung field, which irradiates both breasts entirely, outperformed a higher-dose mantle field in the cohort data. Magnetic resonance imaging is favoured because dense young breast tissue reduces the sensitivity of mammography.
Query for this technology: (TITLE:"Breast cancer after chest radiotherapy in childhood, and the screening that follows" OR ABSTRACT:"Breast cancer after chest radiotherapy in childhood, and the screening that follows") AND (cancer OR tumor OR tumour OR oncology OR carcinoma OR lymphoma OR leukemia OR leukaemia OR myeloma OR sarcoma OR melanoma OR glioma). Results are unfiltered search hits about Breast cancer after chest radiotherapy in childhood, and the screening that follows, not a curated reading list.
Shares Second cancers after childhood cancer: the risk by treatment, and why it is falling, Childhood Cancer Survivor Study (CCSS), Wilms tumour (nephroblastoma), Radiotherapy and the tags rejuvenation, survivorship, paediatric, late-effects.
Shares International Guideline Harmonization Group for late effects of childhood cancer, The Children's Oncology Group Long-Term Follow-Up Guidelines, Wilms tumour (nephroblastoma), Ewing sarcoma and the tags rejuvenation, survivorship, paediatric, late-effects.
Shares International Guideline Harmonization Group for late effects of childhood cancer, The Children's Oncology Group Long-Term Follow-Up Guidelines, Wilms tumour (nephroblastoma), Childhood cancers (all types) and the tags rejuvenation, survivorship, paediatric, late-effects.
Shares International Guideline Harmonization Group for late effects of childhood cancer, The Children's Oncology Group Long-Term Follow-Up Guidelines, Childhood Cancer Survivor Study (CCSS), Radiotherapy and the tags rejuvenation, survivorship, paediatric, late-effects.
Shares International Guideline Harmonization Group for late effects of childhood cancer, The Children's Oncology Group Long-Term Follow-Up Guidelines, Childhood Cancer Survivor Study (CCSS), Radiotherapy and the tags rejuvenation, survivorship, paediatric, late-effects.
Shares International Guideline Harmonization Group for late effects of childhood cancer, The Children's Oncology Group Long-Term Follow-Up Guidelines, Childhood Cancer Survivor Study (CCSS), Wilms tumour (nephroblastoma) and the tags rejuvenation, survivorship, paediatric, late-effects.
Shares The Children's Oncology Group Long-Term Follow-Up Guidelines, Childhood Cancer Survivor Study (CCSS), Radiotherapy, Childhood cancers (all types) and the tags rejuvenation, survivorship, paediatric, late-effects.
Shares International Guideline Harmonization Group for late effects of childhood cancer, The Children's Oncology Group Long-Term Follow-Up Guidelines, Radiotherapy, Childhood cancers (all types) and the tags rejuvenation, survivorship, paediatric, late-effects.