Editing Breast cancer (section)

== '''Radiotherapy''' ==

* Treatment protocol
** Typically 40Gy over about three weeks, in 15 minute sessions on weekdays
** Post-menopausal women with non-high grade, ER-positive, stage I breast cancer can be treated with a shorter 3 week course
** Partial breast irradiation focuses RTX around the tumour bed
* Contraindications to radiotherapy
** Absolute
*** Pregnancy
** Relative
*** Systemic scleroderma or active SLE ''(other collagen vascular diseases are not contraindications to radiation, although patients should not be taking immunosuppressants such as methotrexate because they are radiosensitisers)''
*** Prior radiation to breast or chest wall
*** Severe pulmonary disease
*** Severe cardiac disease (if tumour is left-sided)
*** Inability to lie supine
*** Inability to abduct arm on affected side
*** P53 mutation ''(highly susceptible to radiation-induced cancers)''
* To whole breast, after breast-conserving therapy
** Radiotherapy reduces local recurrence after WLE at 20 years from 39.2% to 14.3% in node-negative patients; and from 44.2% to 8.8% if the patient has positive nodes and therefore receives chemotherapy
** Improved breast cancer specific survival by 18%
** Can consider omitting RTX in patients age >70 with stage I hormone receptor positive breast cancer treated by partial mastectomy and tamoxifen (recurrence rate 2% with radiotherapy, 10% without)
** RT boost to tumour bed if high-risk factors are present:
*** Younger age
*** High-grade cancer
*** Margin involvement
*** Significant in-situ disease
*** Higher T stage
* Indications for axillary radiotherapy
** Instead of dissection in node-positive patients
*** AMAROS trial - ALND vs axillary RTX in T1/T2, pN1 - comparable long-term control, with less lymphoedema in the RTX group
** In patients with very high axillary tumour burden in addition to ALND
* To mastectomy site (PMRT - post-mastectomy radiotherapy)
** Indications
*** High-risk: Stage III breast cancer (decreased 15 year locoregional recurrence from 29% to 8% and breast cancer mortality from 60% to 55%)
*** Intermediate risk: Stage II disease with extracapsular extension, lymphovascular invasion, age <40yo, clear/positive surgical margins, nodal positivity ratio >20%
*** Also consider for close or involved margins
* Reconstruction and radiotherapy
** Oncological outcomes take priority
** Discuss in MDT
** Permanent silicon implants are high-risk of capsular contracture (pain, poor cosmesis, revision) in the setting of irradiated tissue, regardless of whether the silicon was in situ during radiotherapy
** Autologous tissue tolerates radiotherapy better
** [[File:Accelerated partial irradiation.png|none|thumb|693x693px|From Sabiston's Textbook of Surgery]]

* Intra-operative radiotherapy
** Immature technique, lacking robust long-term follow-up
** Probably offers advantages for appropriately chosen patients
** I don't think this is done in Australia
**[[File:Untitled picture.png|frameless|631x631px]]