SENTINEL LYMPH NODE MICROMETASTASIS IN BREAST CANCERAnthony Fong

Yan Chai Hospital

SENTINEL LYMPH NODE

First node encountered by tumor cell Will spread first to lymph nodes close to the

tumor before it spreads to other parts of the body

If the sentinel lymph node does not contain cancer, then there is a high likelihood that the cancer has not spread to any other area of the body

Veronesi U, Luini A, Galimberti V, Marchini S, Sacchini V, Rilke F.Eur J Surg Oncol. 1990 Apr;16(2):127-33.Extent of metastatic axillary involvement in 1446 cases of breast cancer.

SENTINEL LYMPH NODE False negative value 8.8% Negative predictive value 95.4%

http://www.mayoclinic.org/breast-cancer

LOCALIZATION OF SENTINEL LYMPH NODE

Isosulfan blue dye Technetium-99 sulfur colloid False negative rate : 5.8%

http://www.cancernetwork.com

McMasters KM, Tuttle TM, Carlson DJ et alSentinel lymph node biopsy for breast cancer: a suitable alternative to routine axillary dissection in multi-institutional practice when optimal technique is used.J Clin Oncol. 2000 Jul;18(13):2560-6.

PATHOLOGICAL EXAMINATION OF SLN

H & E staining Immunohistochemistry Molecular techniques

Klevesath MB, Bobrow LG, Pinder SE, Purushotham AD.The value of immunohistochemistry in sentinel lymph node histopathology in breast cancer.Br J Cancer. 2005 Jun 20;92(12):2201-5.

MICROMETASTASIS&ISOLATED TUMOR CELLS

7TH A

JCC

7th AJCC

PATHOLOGICAL STAGING OF LYMPH NODE

Pathologic pN

pNX Regional lymph nodes cannot be assessed (for example, previously removed, or not removed for pathologic study)

pN0 No regional lymph node metastasis identified histologically .

pN0(i−) No regional lymph node metastases histologically, negative IHC

pN0(i+) Malignant cells in regional lymph node(s) no greater than 0.2 mm (detected by H&E or IHC including ITC)

pN0(mol−) No regional lymph node metastases histologically, negative molecular findings (RT-PCR)

pN0(mol+) Positive molecular findings (RT-PCR)**, but no regional lymph node metastases detected by histology or IHC

pN1 Micrometastases; or metastases in 1–3 axillary lymph nodes; and/or in internal mammary nodes with metastases detected by sentinel lymph node biopsy but not clinically detected

pN1mi Micrometastases (greater than 0.2 mm and/or more than 200 cells, but none greater than 2.0 mm)

PATHOLOGICAL STAGING OF LYMPH NODE

Pathologic pN

pNX Regional lymph nodes cannot be assessed (for example, previously removed, or not removed for pathologic study)

pN0 No regional lymph node metastasis identified histologically .

pN0(i−) No regional lymph node metastases histologically, negative IHC

pN0(i+) Malignant cells in regional lymph node(s) no greater than 0.2 mm (detected by H&E or IHC including ITC)

pN0(mol−) No regional lymph node metastases histologically, negative molecular findings (RT-PCR)

pN0(mol+) Positive molecular findings (RT-PCR), but no regional lymph node metastases detected by histology or IHC

pN1 Micrometastases; or metastases in 1–3 axillary lymph nodes; and/or in internal mammary nodes with metastases detected by sentinel lymph node biopsy but not clinically detected

pN1mi Micrometastases (greater than 0.2 mm and/or more than 200 cells, but none greater than 2.0 mm)

ASCO GUIDELINE

Recommends routine ALND for patients with a positive SNB on the basis of routine histopathologic examination.

It remains unclear whether isolated tumor cells (pN0) detected with hematoxylin and eosin staining or special stains represent an adverse prognostic indicator.

Metastasis is found in nonsentinel nodes in about 10% of patients with isolated tumor cells in the SLN and in 20% to 35% of patients with micrometastasis in the SLN.

ASCO GUIDELINE

Until further studies addressing the clinical relevance of isolated tumor cells or micrometastases in the SLN are complete, the Panel recommends routine ALND for patients with micrometastases ( >0.2 mm but < 2.0 mm) found on SNB, regardless of the method of detection.

AXILLIARY DISSECTION IN SLN MICROMETASIS

AD IN SLN MICROMETASTASIS

AXILLARY RECURRENCE RATE IN BREAST CANCER PATIENTS WITH NEGATIVE SENTINEL LYMPH NODE BIOPSY OR CONTAINING MICROMETASTASES AND WITHOUT FURTHER LYMPHADENECTOMY: A MONOCENTRIC REVIEW OF 8 YEARS AND 481 CASES

Negative SLNB no additional CALND (n=481) Axillary relapse in only 1 patient (0.2%)

SLNB contained micrometastases and no further CALND (n=45) No axillary relapse in this group

Mean FU time 48 months

AVOIDING AXILLARY TREATMENT IN SENTINEL LYMPH NODE MICROMETASTASES OF BREAST CANCER : A PROSPECTIVE ANALYSIS OF AXILLARY OR DISTANT RECURRENCE

Patient with early breast cancer (tumor <3cm) with favorable characteristics

1178 patient with SLN 59 (5%) had micrometastases 14 (24%) underwent ALND After median 60month, no patient in SLN MM

group without ALND developed axillary recurrence

SLN MM AFFECTING PROGNOSIS

PROGNOSIS

MICROMETASTASES OR ISOLATED TUMOR CELLS AND THE OUTCOME OF BREAST CANCER

Identify women with invasive breast cancer with SLN before 2006 from Netherlands Caner Registry

Include patient with favourable primary tumor characteristics Tumors <= 1cm in diameter, irrespective of

grade Tumors >1cm to <= 3cm, grade 1 or 2

Node negative disease randomly selected from years 2000 and 2001

MICROMETASTASES OR ISOLATED TUMOR CELLS AND THE OUTCOME OF BREAST CANCER

Node negative n = 856

ITC / MM with no adjuvant therapy n = 856

ITC / MM with adjuvant therapy n = 995

MICROMETASTASES OR ISOLATED TUMOR CELLS AND THE OUTCOME OF BREAST CANCER

CONCLUSION

Micro-metastasis in breast cancer indicates a inferior prognosis

Axillary dissection may not be necessary in patient with micrometastasis

Role of adjuvant therapy

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