Locally advanced breast cancer Flashcards
What is locally advanced breast cancer?
Typically refers to stage III disease (T3N1, N2-3, or T4) but can also refer to stage IIB (T3N0) and inflammatory breast cancer. Does not include metastatic disease.
What are the trends in incidence of LABC?
T3-T4 disease incidence has decreased by 27% from 1980 to 1987 due to institution of mammography. SEER database review 92-99 revealed LABC 4.6% of all breast cancers and IBC 1.3%
What are diagnostic criteria for inflammatory breast cancer?
Rapid onset of breast erythema, edema, and/or peau d’organge and/or warm breast with or without an underlying palpable mass
Duration of hx no more than 6 months
Erythema occupying at least 1/3 of breast
Pathologic confirmation of invasive carcinoma
What is the pathognomonic feature more characteristic of IBC than other forms of LABC?
Tumor emboli (dermal lymphatic invasion) in the dermis of the skin overlying the breast
What is the prevalence of IBC?
1-4% of breast cancer cases are IBC, 70% present with regional disease and 30% with distant disease
What are the histologic subtypes of LABC?
Same as earlier stage disease: invasive ductal carcinomas, tubular, medullary, mucinous
Are there genetic/molecular factors associated with LABC?
No marker is used to define LABC but HER2+, BRCA+, triple negative are associated with aggressive phenotypes.
Workup for locally advanced invasive breast cancer
H&P, CBC, LFT, ER/PR/HER2, bilateral diagnostic mammogram, imaging with US, CT, PET, bone scan and MRI are optional per NCCN 2018
What are the 5 regional LN stations for breast cancer?
Station I: nodes inf/lat to pectoralis minor muscle
Station II: nodes deep to pectoralis minor and the interpectoral Rotter nodes
Station III: nodes sup/med to pectoralis minor
Station IV: SCV nodes
Station V: IM nodes
What are the most important factors that predict LRR for LABC?
Increasing number of LNs+, tumor size
What are the basic principles for treating LABC?
Inoperable LABC: neoadjuvant chemo to shrink the tumor and potentially conver to operable
Operable LABC: neoadj or adj chemo are used with mastectomy. PMRT indicated for all stage III disease. Hormonal therapy if ER+ or trastuzumab if HER2+
What is a Halsted radical mastectomy?
Resection of all breast parenchyma with overlying skin and major/minor pectoral muscles en bloc with axillary lymph nodes
What is spared with a modified radical mastectomy?
MRM spares the pectoralis muscles
What is spared with a total or simple mastectomy?
In total/simple mastectomy only the breast tissue is removed with overlying skin. Axillary LNs are not dissected.
What is considered an adequate axillary LND for purposes of staging and clearance?
Resection of levels I-II. The LNs and axillary fat pad need to be removed en bloc. Axillary LND is considered full if >10 LN are removed without neoadj chemo. LN yield is often less after chemo. If suspicious nodes are palpable intraoperatively then level III dissection may be indicated.
Which trial demonstrated that not all patients with SLNBx+ need completion axillary LND?
ACOSOG Z11 - patients with 1-2 SLNBx+ nodes randomized to completion ALND + RT vs RT alone. No difference in breast or axillary recurrence
Do clinically node+ patients always need ALND?
Yes. No matter what upfront treatment (surgery, neoadjuvant chemo) full axillary LND is indicated. Omission of ALND only on protocols.
What is standard systemic chemotherapy for LABC?
Antrhacycline and taxane based regimen (doxorubicin/cyclophosphamide (AC) and paclitaxel)
Does adding paclitaxel to standard AC chemo improve outcomes for patients with LABC?
Yes. Improved response rates, DFS and OS seen on NSABP B27 (improved pCR in group receiving preop AC+T), CALGB 9344 (improved DFS and OS), ECOG E1199 (improved DFS and OS)
Which meta-analysis shows benefit of anthracyclines?
EBCTG/Oxford overview: antrhacyclines > CMF > no chemo
What does “dose-dense” chemo mean?
Dose-dense chemo is administered q2wks as opposed to q3wks
Has dose-dense chemo been proven to be superior in a prospective randomized trial?
Yes. Intergroup C9741 randomized patients to q2wk vs q3wk AC+T and found improved 4yr DFS (75% to 82%)
What is the rationale for the use of neoadjuvant chemotherapy for LABC?
To convert patients from unresectable LABC to resectable. Can also make less extensive surgeries possible.
Which patients have inoperable disease and need neoadjuvant chemotherapy?
Women with fixed axillary LN (stage N2a), major skin involvement (stage T4b-T4d) +/- CW involvement
What major study determined whether neoadjuvant chemotherapy improves survival compared to adjuvant chemotherapy in LABC?
NSABP B18 - compared preop AC to postop AC. 16yr follow up w/o significant difference in OS or DFS but there is a trend for women <50y for improved DFS and OS in the preop group
What procedures should be done prior to starting neoadjuvant chemotherapy for LABC?
Core biopsy and clip localization of breast tumor (in case pt has a CR to chemo). If clinically node+, also place clip in involved LN prior to chemo
In NSABP 18 and 27, did pCR at time of surgery correlate with good OS and DFS outcomes?
Yes. Both NSABP 18 and 27 showed correlation between pCR and improved OS and DFS compared to non-pCR patients
What other seminal neoadjuvant chemo trials (beyond NSABP 18 and 27) adressed neoadjuvant vs. adjuvant chemotherapy and its role regarding BCS?
EORTC 10902 randomized patients with early stage BC to preop vs. postop chemotherapy. No difference at 10 yr f/u in OS or LRR but improved rates of BCS were seen in neoadjuvant chemo arm.