BREAST CANCER Part 01

Epidemiology   most common cancer in women (excluding skin) second leading cause of cancer mortality in women most...

Epidemiology

 

1. most common cancer in women (excluding skin)
2. second leading cause of cancer mortality in women
3. most common cause of death in 5th decade
4. lifetime risk of 1/9 

 

Etiology

1. multifactorial
2. genetics play key role in 15% of cases

 

Risk factors

1. age - 80% > 40
2. sex - 99% female
3. 1st degree relative with breast cancer
• risk increased further if relative was premenopausal
4. geographic - highest national mortality in England and Wales, lowest in Japan
5. nulliparity
6. late age at first pregnancy
7. menarche < 12 ; menopause > 55
8. obesity
9. excessive alcohol intake
10. some forms of mammary dysplasia
11. prior history of breast cancer
12. history of low-dose irradiation
13. prior breast biopsy regardless of pathology
14. BCP/estrogen replacement may increase risk 

 

Diagnostic workup of breast mass

History

 

1. how long the lump has been noted
2. any changes that have been observed
3. history of biopsy or breast cancer
4. breast CA risk factors should be noted, but their presence or absence do not influence decision to further investigate breast lump
   

Physical

1. to identify those features that distinguish malignant from benign lump
2. benign: smooth, well-demarcated, mobile
3. malignant: irregular, poorly defined, less mobile
   

Other signs of malignancy

1. skin changes: edema, dimpling, retraction, redness, ulceration
2. nipple: bloody discharge, crusting, ulceration, inversion
3. prominent veins, palpable axillary/supraclavicular lymph nodes, arm edema

 

Mammogram

1. stellate appearance and spiculated border - pathognomonic of breast cancer
2. microcalcifications
3. ill-defined lesion border
4. lobulation
5. architectural distortion
6. increased vascularity
7. interval mammographic changes                                           
   

NORMAL MAMMOGRAM DOES NOT RULE OUT SUSPICION OF CANCER (BASED ON CLINICAL FINDINGS)

Fine Needle Aspiration

 

1. if non-bloody fluid and mass completely disappears, diagnosis is simple cyst - no need for cytology
2. if bloody/no fluid or mass does not fully disappear - send cells for cytology

Biopsy

1. whenever reasonable doubt remains as to whether a lump is benign or malignant
2. core biopsy - removal of core of intact tissue through 14-gauge needle
3. excisional biopsy - surgical removal of entire lesion with
4. cuff of normal tissue

 

Staging

 
Clinical vs. pathological

Cinical:

1. assess tumour size, nodal involvement, and metastasis
2. tumour size by palpation, mammogram
3. nodal involvement by palpation
4. metastasis by physical exam, CXR, LFTs
   

Pathological

1. histology
2. axillary dissection should be performed for accurate
3. staging and to reduce risk of axillary recurrence
4. estrogen/progesterone receptor testing

Staging of Breast Cancer (American Joint Committee)

Stage	Tumour	Nodes (regional)	Metastasis
0	in situ	none	none
1	< 2 cm	none	none
II	< 2 cm or 2-5 cm or > 5 cm	movable ipsilateral none or movable ipsilateral none	none None none
III	any size or skin/chest wall invasion	fixed ipsilateral or internal mammary any	none none
IV	any tumour	any	distant