Doses to internal organs for various breast radiation techniques - implications on the risk of secondary cancers and cardiomyopathy

<p>Abstract</p> <p>Background</p> <p>Breast cancers are more frequently diagnosed at an early stage and currently have improved long term outcomes. Late normal tissue complications induced by adjuvant radiotherapy like secondary cancers or cardiomyopathy must now be avoided at all cost. Several new breast radiotherapy techniques have been developed and this work aims at comparing the scatter doses of internal organs for those techniques.</p> <p>Methods</p> <p>A CT-scan of a typical early stage left breast cancer patient was used to describe a realistic anthropomorphic phantom in the MCNP Monte Carlo code. Dose tally detectors were placed in breasts, the heart, the ipsilateral lung, and the spleen. Five irradiation techniques were simulated: whole breast radiotherapy 50 Gy in 25 fractions using physical wedge or breast IMRT, 3D-CRT partial breast radiotherapy 38.5 Gy in 10 fractions, HDR brachytherapy delivering 34 Gy in 10 treatments, or Permanent Breast ¹⁰³Pd Seed Implant delivering 90 Gy.</p> <p>Results</p> <p>For external beam radiotherapy the wedge compensation technique yielded the largest doses to internal organs like the spleen or the heart, respectively 2,300 mSv and 2.7 Gy. Smaller scatter dose are induced using breast IMRT, respectively 810 mSv and 1.1 Gy, or 3D-CRT partial breast irradiation, respectively 130 mSv and 0.7 Gy. Dose to the lung is also smaller for IMRT and 3D-CRT compared to the wedge technique. For multicatheter HDR brachytherapy a large dose is delivered to the heart, 3.6 Gy, the spleen receives 1,171 mSv and the lung receives 2,471 mSv. These values are 44% higher in case of a balloon catheter. In contrast, breast seeds implant is associated with low dose to most internal organs.</p> <p>Conclusions</p> <p>The present data support the use of breast IMRT or virtual wedge technique instead of physical wedges for whole breast radiotherapy. Regarding partial breast irradiation techniques, low energy source brachytherapy and external beam 3D-CRT appear safer than ¹⁹²Ir HDR techniques.</p

Second malignancies after breast cancer: the impact of different treatment modalities

Treatment for non-metastatic breast cancer (BC) may be the cause of second malignancies in long-term survivors. Our aim was to investigate whether survivors present a higher risk of malignancy than the general population according to treatment received. We analysed data for 16 705 BC survivors treated at the Curie Institute (1981–1997) by either chemotherapy (various regimens), radiotherapy (high-energy photons from a 60Co unit or linear accelerator) and/or hormone therapy (2–5 years of tamoxifen). We calculated age-standardized incidence ratios (SIRs) for each malignancy, using data for the general French population from five regional registries. At a median follow-up 10.5 years, 709 patients had developed a second malignancy. The greatest increases in risk were for leukaemia (SIR: 2.07 (1.52–2.75)), ovarian cancer (SIR: 1.6 (1.27–2.04)) and gynaecological (cervical/endometrial) cancer (SIR: 1.6 (1.34–1.89); P<0.0001). The SIR for gastrointestinal cancer, the most common malignancy, was 0.82 (0.70–0.95; P<0.007). The increase in leukaemia was most strongly related to chemotherapy and that in gynaecological cancers to hormone therapy. Radiotherapy alone also had a significant, although lesser, effect on leukaemia and gynaecological cancer incidence. The increased risk of sarcomas and lung cancer was attributed to radiotherapy. No increased risk was observed for malignant melanoma, lymphoma, genitourinary, thyroid or head and neck cancer. There is a significantly increased risk of several kinds of second malignancy in women treated for BC, compared with the general population. This increase may be related to adjuvant treatment in some cases. However, the absolute risk is small

Patella osteochondritis dissecans end stage: The osteochondral mosaicplasty option.

INTRODUCTION: Patellar damage during osteochondritis dissecans of the knee is rare. There were two objectives to this study: evaluate the functional results of surgical treatment by mosaicplasty in this disease as well as evaluate articular surface reconstruction and cylindrical bone plugs incorporation. MATERIALS AND METHODS: Six consecutive cases of patella osteochondritis dissecans in young athletes were treated using mosaicplasty by the same senior surgeon between 2002 and 2007. All these cases presented ICRS stage IV osteochondritis dissecans with an empty defect lesion. The average age at diagnosis was 20.5 \ub1 9.2 years old. The pre- and post-operative clinical evaluation was based on the IKDC subjective knee evaluation, the Lysholm and Tegner scores, CT arthrography and MRI. RESULTS: Evaluation of the functional results of surgical treatment at a mean follow-up of 26 months showed an average IKDC subjective evaluation score of 66.3, a Lysholm score of 85 and a Tegner score of 5.7 (37.2, 58.3 and 3.5 respectively before surgery). The radiological evaluation showed articular surface reconstruction with satisfying congruency and good incorporation of the graft into the bone at the receptor site, except in one patient in whom a 5mm diameter cartilage defect and a loose body were identified. DISCUSSION: Osteochondral grafting with the mosaicplasty technique has been shown to be effective and give satisfying functional results. The problem of the per-operative cylindrical bone plugs choice requires to be addressed during the procedure course itself, according to the patella lesion location