Breast Early Stage Part 3 Flashcards
Give the four Accelerated Partial Breast Irradiation techniques.
Multicatheter Interstitial Techniques
MammoSite
External-Beam Conformal Radiation
Intraoperative Partial Breast Irradiation
In multicatheter technique:
Total No. of catheters and planes are dependent on the:
Total No. of catheters and planes: dependent on the: size extent, and shape of the target Due to complexity: less widely used
Employs a single balloon catheter introduced into the lumpectomy site either at the time of lumpectomy or percutaneously after the procedure
Mammosite
Dose of the mammosite?
Dose: 3.4 Gy, 1 cm 2x daily (34 Gy for 5 days)
In APBI,
Over 70% of patients in randomized trial are opting for 3D-CRT due to?
Non-invasiveness
Homogeneous Dose Distribution
Challenges in EBRT APBI?
Daily positioning of the target
Movement with breathing
Delivery of higher doses to surrounding normal breast tissue than with the brachytherapy
Dose of EBRT APBI
Dose: 38.5 Gy in 3.85 Gy/fx delivered twice daily
RT: delivered in a single intraoperative dose to the lumpectomy site at the time of surgery
Intraoperative electrons or intraoperative photons
Intraoperative Accerlerated Partial Breast Irradiation
What is the dose for IORT APBI?
Single fraction of 21 Gy is equivalent to 60Gy/2Gy/fx
ASTRO Recommendations on suitability of patients receiving APBI?
Suitable for patients: (2009) ≥60yrs Node (-) Invasive ductal tumors ≤2cm (-) margins ER (+) (-) lymphovascular space involvement
What are the four important factors that can affect cosmesis?
- Surgical factors to be considered include extent of surgical resection, re-excision, orientation and length of the scar, closure or not of the tylectomy cavity, separate or continuous axilla–tylectomy scars, extent of the axillary dissection, and whether an ellipse of skin over the tumor was removed.
- Radiation therapy factors are doses to the whole breast with tangential portals, homogeneity of dose throughout the breast (use of wedge or compensating filters), use of bolus, fractionation, overall duration of therapy including breaks, type and dose of boost, beam energy, and volume treated (whether peripheral lymphatic irradiation is administered).
- Chemotherapy issues include cytotoxic agents used, timing and sequence relative to radiation therapy, and doses and combinations of drugs.
- Host factors include size and shape of the breast, age, race, compliance with care and hygiene, concurrent medical illnesses (e.g., hypertension, diabetes, CVD), and intrinsic sensitivity to radiation
In surgical aspect what are the factors Associated with lower rates of excellent/good cosmesis:
Reexcision of primary site
>100cm3 breast tissue resection
Skin resection area >20cm2
Axillary surgery DOES NOT affect Breast Cosmesis
T or F?
True
Radiation factors affecting cosmesis?
Treatment volume (tangential breast fields only vs. three fields or more) Whole breast dose (>50 Gy) Total dose to the tumor site (>65 Gy) Optimum dose distribution created with use of compensating filters
NOT FACTORS: Daily fractions size (1.8 vs 2 Gy) Boost vs No boost Use and type of boost (brachytherapy vs. electrons) Total irradiation dose Use of bolus
In EORTC trial, what are the factors showing worse cosmetic outcomes
Factors associated with worse cosmesis: Inferior tumor location Large excision volume Presence of postoperative complications Radiation therapy boost
Most frequent findings in imaging after BCS in early stage Breast CA
parenchymal distortion and fibrosis
at the tumor excision site (secondary to surgical scar and irradiation)
skin thickening
seen in 90% of patients, which may be diffuse or more prominent at the surgical excision site
calcifications
due to fat necrosis, which are coarse and round and have radiolucent centers
drew et al compared MRI vs Mammo and Clin exam
What is the conclusion?
CONCLUSION: When combined, clinical examination and mammography are as sensitive as MRI of the breast for the detection of locoregional recurrence, but MRI has greater specificity.
Risk of arm edema increases when axillary dissection and axillary radiation therapy are used
What is the most common presentation of lymphedema?
Swelling
Factors associated with arm edema?
More extensive axillary dissection (Beyond Level II - Midline)
Axillary Surgery plus irradiation
Younger women with axillary node dissection
> 13 LN dissected
Unusual variant of panniculitis thickened sclerotic septa:
thick and thin collagen bundles
lobular panniculitis
Pseudosclerodermatosus panniculitis
Tamoxifen has been shown to induce secretion of ________, which has been implicated in pathogenesis of radiation fibrosis.
tumor growth factor-β
True or false?
Skin effects after postlumpectomy radiation therapy may be affected more significantly by the increase in the dose of radiation per fraction rather than by the total dose
True
incidence of brachial plexopathy was significantly higher when the axillary dose was ______ Gy
> 50 Gy
Most common presentation of pneumonitis
Dry cough
