Invasive breast cancer
The article deals with invasive breast cancer and the evaluation of hormone receptor & HER2 status. Non-invasive breast cancer is dealt with in non-invasive breast cancer.
Introduction
Types of invasive breast cancer
Types:Ref.: [1]
- Ductal - also known as no specific type (NST) - 79%.
- Lobular 10%.
- Cribriform (tubular) 6%.
- Mucinous (colloid) 2%.
- Medullary 2%.
- Papillary 1%.
- Metaplastic <1%.
Others:
- Angiosarcoma - post-radiation ~ 10 years.[2]
Familial breast cancer
BRCA1 vs. BRCA2:[3]
- BRCA1:
- Younger.
- Ovarian cancer.
- Worse types of breast cancer (e.g. triple negative breast cancer: PR-, ER-, HER2/neu-).
- BRCA2:
- Older.
- Like sporatic.
- Male breast cancer.
- BOTH are associated with increased risk of (memory device CPP):
Breast IHC
Subtyping breast cancer
- DCIS vs LCIS:[4]
- E-cadherin (+ve DCIS, -ve LCIS).
- antibody 34betaE12 (+ve perinuclear LCIS, -ve DCIS).
- CAM5.2 (peripheral stain = DCIS, perinuclear stain = LCIS).
- CAM5.2 is against CK8.
- Beta-catenin (-LCIS, +DCIS).
- ADH and DCIS:[7]
- E-cadherin.
- Present in most epithelial cells.
- Lost in LCIS & invasive lobular carcinoma.
- SMMHC (smooth muscle cell myosin heavy chain).
- Marks myoepithelial cells.
- E-cadherin.
- Immunostaining of any sentinel lymph nodes - to look for isolated tumour cells and small lymph node mets.
- Sunnybrook uses CAM5.2.
- ER (estrogen receptor).
- Positive in most breast cancers; +ve in ~75-80%.[8]
- PR (progesterone receptor).
- Positive in most breast cancers; +ve in ~65-70%.[8]
- HER2/neu.
- Usually negative; -ve in 70-80%.[8]
- Positivity association with a worse prognosis.
ER & PR scoring[8]
- Give a percentage, i.e. 0-100%.
- Important cut points: 1% and 10%.
- 0% = negative - not treated.
- <10% = low positivity - treated.
- Important cut points: 1% and 10%.
Notes:
- Normal breast epithelial cells have a patchy staining for ER and PR.
- Evaluated on the invasive component.
HER2 scoring[8]
Score | Staining intensity | Cells stained (%) | Membrane staining | Management | Percentage of cases |
0 | nil | <10% | incomplete | No HER2 blocker | ~60% |
1+ | minimum | >10% | incomplete | No HER2 blocker | ~10% |
2+ | weak | >10% | complete | Needs SISH or FISH | ~10% |
3+ | strong | >10% | complete | HER2 blocker | ~20% |
Notes:
- Normal breast epithelial cells do not stain with HER2.
- Evaluated on the invasive component.
- SISH = silver in situ hybridization.
- FISH = fluorescence in situ hybridization.
Clinical
- ER & PR status determine whether a patient will get tamoxifen or other estrogen receptor modulators, such as raloxifene (Evista).
- HER2 status determines whether patient will get traztuzumab (Herceptin) or other HER2/neu modulators.
Characteristics of the subtypes
List of subtypes
Epithelial
Counterparts of in situ lesions:
- Invasive ductal carinoma, not otherwise specified.
- Invasive lobular carcinoma.
- Invasive cribriform carcinoma.
- Invasive papillary carcinoma.
- Invasive micropapillary carcinoma.
Other epithelial tumours:
- Tubular carcinoma.
- Medullary carcinoma.
- Mucinous carinoma.
- Neuroendocrine tumours.
- Apocrine carcinoma.
- Lipid-rich carcinoma.
- Secretory carcinoma.
- Oncocytic carcinoma.
- Glycogen-rich clear cell carcinoma.
Epithelial tumours seen in the salivary gland:
- Adenoid cystic carcinoma
- Acinic cell carcinoma.
Clinically diagnosed:
- Inflammatory carcinoma.
In situ lesions:
- Ductal carcinoma in situ.
- Lobular carcinoma in situ.
Proliferative lesions:
- Usual ductal hyperplasia.
- Flat epithelial atypia.
- Atypical ductal hyperplasia.
Ductal carcinoma
- AKA "NST" = No Specific Type.
Microscopic
Features:
- Cohesive cells - forming ducts or in sheets.
- Nuclear pleomorphism.
Clinical
- Typically: ER+, PR+, HER2-.
Lobular carcinoma
General
Microscopic
Features:
- "Single file" - cell line-up in a row.
- Cell should not be cohesive -- lymphoma should briefly come to mind.
- primary lymphoma of the breast exists... but it is extremely rare.
- Cell should not be cohesive -- lymphoma should briefly come to mind.
- NO gland formation.
- If it forms glands... it is more likely NST.
- May have signet ring morphology.
- NO desmoplastic reaction, i.e. the stroma surrounding the tumour cells should look benign and undisturbed.
Note:
- commonly have low grade nuclear features
Subclassification:
- Classic lobular carcinoma.
- Low nuclear grade - NO significant variation of nucleus size.
- Pleomorphic lobular carcinoma.
- Significant nuclear atypia.
Note: Some pathologist grade lobular carcinoma like other types and avoid the term "pleomorphic lobular carcinoma."[10]
Medullary carcinoma
General
- Some pathologists don't believe this exists.
Epidemiology:
- Thought to have a better prognosis that no special type (NST).
- Association with BRCA1 mutations.
Microscopic
Features:
- Lesion has well-circumscribed border.
- Syncytial growth pattern = clumps of cells with poorly defined cell borders.
- Lymphocytic infiltrate.
- High nuclear grade (as per Nottingham grading system).
- No tubule formation.
Tubular carcinoma
General
Epidemiology:
- Typically excellent prognosis.
- Hormone receptors commonly present.
Microscopic
- Well-formed tubules.
- Myoepithelial cells absent.
- +/- Cribriform spaces.
- Apocrine snouts typical.
- +/- Calcification.
- Angled ducts common: "prows" - important feature (low power).
- Looks benign to the uninitiated -- IMPORTANT.
Notes:
- Prow = front of a ship.
DDx:
Metaplastic carcinoma
General
- May be difficult to diagnosis.
- Prognosis - poor.
Microscopic
Features:[14]
- Malignant mesenchymal elements:
- Spindle cells
- +/-Adenocarcinoma.
- +/-Squamous carcinoma.
Notes:
- If it looks like squamous cell carcinoma... in the breast it is metaplastic carcinoma.
Images: Metaplastic carcinoma (breastpathology.info).[14]
IHC
- S100 -ve (r/o melannoma).
- AE1/AE3 +ve (epithelial elements only).
- CK7 +ve (epithelial elements only).
- p63 +ve (epithelial elements only).
- Vimentin +ve.
- Desmin -ve.
- EMA -ve. (???)
Grading breast cancer
Most common system: Nottingham (aka Scarff-Bloom-Richardson) which is based on:
- Nuclear grade.
- Small, regular (1.5-2x RBC dia.) = 1.
- Moderated variability = 2.
- Marked variation (>2.5x RBC dia.) = 3.
- Tubule formation.
- Majority of tumour - tubules >75% = 1.
- Moderate - 10% to 75% = 2.
- Minimal <10% = 3.
- Mitotic rate.
- 0-5 mitosis/10 HPF (1.52 mm^2 --or-- 0.0152 mm^2 * 10) = 1.
- 6-10 mitosis/10 HPF (1.52 mm^2) = 2.
- >11 mitosis/10 HPF (1.52 mm^2) = 3.
Mnemonic: TMN = tubule formation, mitotic rate, nuclear grade.
Notes:
- Elston & Ellis devised the system that is used.[15] They also wrote a follow-up article in 2002.[16]
Note about mitosis counting
- One MUST adjust for the size of the field of view.
- Most of the Resident scopes have an eye piece diameter of 22 mm. Therefore, the field diameter at 40 X is approximately 22 mm / 40 X ~= 0.55 mm and the field of view is pi/4*(0.55 mm)^2 = 0.2376 mm^2.
- Thus, on a resident scope (with a FOV of 0.2376 mm^2) one should sample 6 or 7 fields of view (FsOV).
- Calculation: 1.52 mm^2 (sampling area) / 0.2376 mm^2 (area / FOV ) = 6.40 FsOV.
- Thus, on a resident scope (with a FOV of 0.2376 mm^2) one should sample 6 or 7 fields of view (FsOV).
- RANT: Sampling 10 fields, where the field of view (FOV) is 0.152 mm^2, is not the same as sampling ten fields, where the FOV is 0.312 mm^2. It surprises me that Elston & Ellis ignore the fact that "10 HPFs" on different microscopes represent different sample areas and that they do not standardize the sampling area.
Calculating Nottingham score
- Grade I = 3-5 points.
- Grade II = 6-7 points.
- Grade III = 8-9 points.
Notes:
- I've found most tumours are grade II.
- The mitotic score is usually 1/3.
- The nuclear score is rarely 1/3 -- even in the tubular subtype.[17]
Staging breast cancer
Definitions:[18]
- Isolated tumour cells: <=0.2 mm and <200 cells.
- Micrometastasis: <=0.2 cm and ( >0.2 mm or >=200 cells ).
- pT1: <= 2 cm.
- pT1mic <= 0.1 cm.
- pT1a > 0.1 cm and <= 0.5 cm.
- pT1b > 0.5 cm and <= 1.0 cm.
- pT1c > 1.0 cm and <= 2.0 cm.
- pT2: > 2 cm and <= 5 cm
- pT3: > 5 cm.
- pT4: chest wall or skin involvement.
Lymph nodes:[21]
- pN0: nil.
- pN0(i+): <=0.2 mm and <200 cells.
- pN1: 1-3 axillary LNs or internal mammary LNs.
- pN1mi: <=0.2 cm and ( >0.2 mm or >=200 cells ).
- pN1a.
- pN1b.
- PN1c.
- pN2 4-9 positive LNs; internal mammary LNs or axillary LNs.
- pN3.
Lymphovascular invasion
There are famous criteria for lymphovascular invasion (LVI).
Rosen criteria for LVI:[22][23]
- Must be outside of the tumour proper.
- LVI is usually very close -- typically within 0.1 cm.
- Contour of cells should differ from possible vessel wall.
- DCIS with retraction artifact mimicing LVI has a contour that matches its surrounding fibrous tissue.
- Endothelium (usu. flat) should be visible.
- Lymphatics are found adjacent to blood vessels - vessels should be present in the vicinity.
Memory device LUBE-O:
- LVI has a Unique contour, Blood vessels and Endothelium in the vicinity, and is Outside of the tumour.
Other
Paget's disease
General
- Associated with underlying breast carcinoma.[24]
Notes:
- Unrelated to Paget disease of the bone.
Microscopic
Features:[24]
- Cells in the epidermis:
- Epitheliod morphology (round/ovoid).
- Cells nested or single.
- Clear/pale cytoplasm key feature - may also be eosinophilic.
- Large nucleoli.
Images:
IHC & DDx:
- See Paget disease.
Sentinel lymph node biopsy
General
- Used for staging, positive LNs = poorer prognosis.
Notes:
- If there is no palpable disease, there is no mortality benefit from axillary lymph node dissection, i.e. positive axillary lymph nodes can be left in situ without affecting outcome.[25]
- This does not negate the fact that a positive sentinel LN biopsy (vs. negative sentinel LN biopsy) portends a poorer prognosis.
Microscopic
Features:
- Atypical cells.
- Nuclear changes of malignancy:
- Nuclear enlargement + variation in size.
- Variation in shape.
- Hyperchromasia and variation in staining.
- Usually in the subcapsular sinuses.
- Nuclear changes of malignancy:
Pitfalls:
- Naevus cell rests.[26]
IHC
Some hospitals use:
- CAM5.2 (LMWK) - to look for isolated tumour cells and small lymph node metstases.
Trivia
Tumour size and lymph node metastases
There is a paper[27] that calculates the probability of lymph node mets based on tumour size. The developed formula is:
Where:
- = the probability of the lymph nodes being positive.
- D = the largest dimension of the tumour in millimetres.
- Z = 1.0041.
- = 0.019.
Selected values
Tumour size (mm) | Probability |
5 | 9 % |
10 | 17 % |
15 | 25 % |
20 | 32 % |
25 | 38 % |
30 | 44 % |
35 | 49 % |
40 | 54 % |
45 | 58 % |
50 | 62 % |
Natural history
There is a theory that up to 22% of small (radiographically detected) breast tumours regress, based on an analysis in a large population.[28] The study is supported by NCI's SEER data.[29] Also, it generated many comments.[28]
Missed macrometastases
The effect of missed macrometastases is small; this implies using IHC to look for isolated tumour cells is money that isn't well spent.[30]
See also
References
- ↑ Cotran, Ramzi S.; Kumar, Vinay; Fausto, Nelson; Nelso Fausto; Robbins, Stanley L.; Abbas, Abul K. (2005). Robbins and Cotran pathologic basis of disease (7th ed.). St. Louis, Mo: Elsevier Saunders. pp. 1143. ISBN 0-7216-0187-1.
- ↑ URL: http://www.breastpathology.info/Case_of_the_month/2007/COTM_1007%20discussion.html. Accessed on: 28 November 2010.
- ↑ Cotran, Ramzi S.; Kumar, Vinay; Fausto, Nelson; Nelso Fausto; Robbins, Stanley L.; Abbas, Abul K. (2005). Robbins and Cotran pathologic basis of disease (7th ed.). St. Louis, Mo: Elsevier Saunders. pp. 1133. ISBN 0-7216-0187-1.
- ↑ Yeh IT, Mies C (March 2008). "Application of immunohistochemistry to breast lesions". Arch. Pathol. Lab. Med. 132 (3): 349-58. PMID 18318578. http://journals.allenpress.com/jrnlserv/?request=get-abstract&issn=0003-9985&volume=132&page=349.
- ↑ Ordóñez NG (March 2006). "Podoplanin: a novel diagnostic immunohistochemical marker". Adv Anat Pathol 13 (2): 83-8. doi:10.1097/01.pap.0000213007.48479.94. PMID 16670463.
- ↑ Kahn HJ, Marks A (September 2002). "A new monoclonal antibody, D2-40, for detection of lymphatic invasion in primary tumors". Lab. Invest. 82 (9): 1255-7. PMID 12218087.
- ↑ Lester, Susan Carole (2005). Manual of Surgical Pathology (2nd ed.). Saunders. pp. 122. ISBN 978-0443066450.
- ↑ 8.0 8.1 8.2 8.3 8.4 Lester, Susan Carole (2005). Manual of Surgical Pathology (2nd ed.). Saunders. pp. 241-2. ISBN 978-0443066450.
- ↑ URL: http://www.asco.org/ascov2/Meetings/Abstracts?&vmview=abst_detail_view&confID=65&abstractID=33006. Accessed on: 19 April 2011.
- ↑ MUA. Jan 22, 2009.
- ↑ Cotran, Ramzi S.; Kumar, Vinay; Fausto, Nelson; Nelso Fausto; Robbins, Stanley L.; Abbas, Abul K. (2005). Robbins and Cotran pathologic basis of disease (7th ed.). St. Louis, Mo: Elsevier Saunders. pp. 1146. ISBN 0-7216-0187-1.
- ↑ URL: http://www.bweems.com/nsj3mp2.jpg.
- ↑ URL: http://surgpathcriteria.stanford.edu/breast/tubularcabr/.
- ↑ 14.0 14.1 URL: http://www.breastpathology.info/Case_of_the_month/2007/COTM_0807%20discussion.html. Accessed on: 28 November 2010.
- ↑ Elston CW, Ellis IO (September 2002). "Pathological prognostic factors in breast cancer. I. The value of histological grade in breast cancer: experience from a large study with long-term follow-up. C. W. Elston & I. O. Ellis. Histopathology 1991; 19; 403-410". Histopathology 41 (3A): 151–2, discussion 152–3. PMID 12405945.
- ↑ Elston CW, Ellis IO (November 1991). "Pathological prognostic factors in breast cancer. I. The value of histological grade in breast cancer: experience from a large study with long-term follow-up". Histopathology 19 (5): 403–10. PMID 1757079.
- ↑ MUA. 20 January 2009.
- ↑ URL: http://www.cancer.org/Cancer/BreastCancer/DetailedGuide/breast-cancer-staging. Accessed on: 8 July 2010.
- ↑ URL: http://www.cancer.org/Cancer/BreastCancer/DetailedGuide/breast-cancer-staging. Accessed on: 8 July 2010.
- ↑ URL: http://www.cancerhelp.org.uk/type/breast-cancer/treatment/tnm-breast-cancer-staging. Accessed on: 9 July 2010.
- ↑ URL: http://www.cancer.org/Cancer/BreastCancer/DetailedGuide/breast-cancer-staging. Accessed on: 8 July 2010.
- ↑ Rosen, PP. (1983). "Tumor emboli in intramammary lymphatics in breast carcinoma: pathologic criteria for diagnosis and clinical significance.". Pathol Annu 18 Pt 2: 215-32. PMID 6674861.
- ↑ URL: http://www.cap.org/apps/docs/committees/cancer/cancer_protocols/2009/InvasiveBreast_09protocol.pdf. Accessed on: 5 August 2011.
- ↑ 24.0 24.1 URL: http://emedicine.medscape.com/article/1101235-diagnosis
- ↑ Giuliano AE, Hunt KK, Ballman KV, et al. (February 2011). "Axillary dissection vs no axillary dissection in women with invasive breast cancer and sentinel node metastasis: a randomized clinical trial". JAMA 305 (6): 569–75. doi:10.1001/jama.2011.90. PMID 21304082.
- ↑ URL: http://www.breastpathology.info/Case_of_the_month/2007/COTM_1107%20discussion.html. Accessed on: 28 November 2010.
- ↑ Porembka, MR.; Abraham, RL.; Sefko, JA.; Deshpande, AD.; Jeffe, DB.; Margenthaler, JA. (Oct 2008). "Factors associated with lymph node assessment in ductal carcinoma in situ: analysis of 1988-2002 seer data.". Ann Surg Oncol 15 (10): 2709-19. doi:10.1245/s10434-008-9947-5. PMID 18483831. http://onlinelibrary.wiley.com/doi/10.1002/cncr.24592/pdf.
- ↑ 28.0 28.1 Zahl, PH.; Maehlen, J.; Welch, HG. (Nov 2008). "The natural history of invasive breast cancers detected by screening mammography.". Arch Intern Med 168 (21): 2311-6. doi:10.1001/archinte.168.21.2311. PMID 19029493.
- ↑ Jatoi, I.; Anderson, WF. (May 2009). "Breast cancer overdiagnosis with screening mammography.". Arch Intern Med 169 (10): 999-1000, author reply 1000-1. doi:10.1001/archinternmed.2009.95. PMID 19468099.
- ↑ Weaver, DL.; Ashikaga, T.; Krag, DN.; Skelly, JM.; Anderson, SJ.; Harlow, SP.; Julian, TB.; Mamounas, EP. et al. (Feb 2011). "Effect of occult metastases on survival in node-negative breast cancer.". N Engl J Med 364 (5): 412-21. doi:10.1056/NEJMoa1008108. PMID 21247310.