Technique of sentinel node biopsy in breast cancer

[The potential role of SPECT/CT in the preoperative detection of sentinel lymph nodes in breast cancer]

Regional lymph node status is the most important prognostic factor in breast cancer. Sentinel lymph node biopsy is the standard method of axillary staging in early breast cancer patients with clinically negative nodes. Preoperative lymphoscintigraphy might support refining biopsy findings by determining the number and location of sentinel lymph nodes. In aged or overweight patients, in the presence of atypical or extra-axillary lymphatic drainage, non-visualized lymph nodes, or sentinel lymph nodes close to the isotope injection site, detection could be aided by a new, hybrid imaging tool: the single-photon emission computed tomography combined with computed tomography (3D SPECT/CT). For the first time in Hungarian language, authors overview the literature: all 14 English-language articles on the implementation of 3D SPECT/CT in sentinel lymph node detection in breast cancer are included. It is concluded that 3D SPECT/CT increases the success rate and quality of preoperative sentinel node identification, and is capable of providing a more accurate staging of breast cancer patients in routine clinical practice.

A longitudinal comparison of arm morbidity in stage I-II breast cancer patients treated with sentinel lymph node biopsy, sentinel lymph node biopsy followed by completion lymph node dissection, or axillary lymph node dissection

Background

Long-term shoulder and arm function following sentinel lymph node biopsy (SLNB) may surpass that following complete axillary lymph node dissection (CLND) or axillary lymph node dissection (ALND). We objectively examined the morbidity and compared outcomes after SLNB, SLNB + CLND, and ALND in stage I/II breast cancer patients.

Materials and Methods

Breast cancer patients who had SLNB (n = 51), SLNB + CLND (n = 55), and ALND (n = 65) were physically examined 1 day before surgery (T0), and after 6 (T1), 26 (T2), 52 (T3), and 104 (T4) weeks. Differences in 8 parameters between the affected and unaffected arms were calculated. General linear models were computed to examine time, group, and interaction effects.

Results

All outcomes changed significantly, mostly nonlinearly, over time (T0–T4). Between T1 and T4, limitations decreased in abduction (all groups); anteflexion, abduction-exorotation, abduction strength (SLNB + CLND, ALND); flexion strength (SLNB + CLND); and arm volume (SLNB, SLNB + CLND). At T4, limitations in anteflexion (SLNB, ALND), abduction (SLNB + CLND, ALND), exorotation (ALND), abduction-exorotation (all groups), and volume (SLNB + CLND, ALND) increased significantly compared with T0. The SLNB group showed an advantage in anteflexion, abduction, abduction-exorotation, and volume. Groups changed significantly but differently over time in anteflexion, abduction, abduction/exorotation, abduction strength, flexion strength, and volume. Effect sizes varied from 0.19 to 0.00.

Conclusion

Initial declines in range of motion and strength were followed by recovery, although not always to presurgery levels. Range of motion and volume outcomes were better for SLNB than ALND, but not strength. SLNB surpassed SLNB + CLND in 2 of the range of motion variables. The clinical relevance of these results is negligible.

SPECT/CT for preoperative sentinel node localization

The value of SPECT/CT for detection and localization of sentinel nodes is reviewed. SPECT/CT depicts extra sentinel nodes and identifies non-nodal tracer accumulation. SPECT/CT is indicated in patients with complex lymphatic drainage as often present in patients with head, neck and scapular melanoma, breast cancer patients with extra-axillary sentinel nodes and patients with tumors draining to pelvic nodes. SPECT/CT also clarifies the drainage pattern of inconclusive conventional images (non-visualization or unclear location of the nodes).

The hidden sentinel node and SPECT/CT in breast cancer patients

PURPOSE

In a minority of breast cancer patients, lymphoscintigraphy shows no lymphatic drainage and 'hidden' sentinel nodes may remain undiscovered. The purpose of this study was to explore the additional value of the recently introduced hybrid SPECT/CT in breast cancer patients with axillary non-visualisation on planar images. The role of blue dye and careful palpation of the axilla was evaluated in patients in whom axillary sentinel nodes remained hidden after SPECT/CT.

METHODS

Fifteen breast cancer patients with non-visualisation on planar lymphoscintigraphy and 13 women with only extra-axillary sentinel nodes underwent SPECT/CT following late planar imaging without re-injection of the radiopharmaceutical.

RESULTS

SPECT/CT visualised lymphatic drainage in eight of the 15 patients (53%) with non-visualisation on planar imaging, depicted nine of the 14 harvested sentinel nodes (64%) and three of five tumour-positive sentinel nodes. In two of the 13 patients (15%) with only extra-axillary sentinel nodes on their planar lymphoscintigram, SPECT/CT showed an axillary sentinel node that appeared to be uninvolved. Careful exploration of the axilla with the combined use of blue dye, a gamma probe and intra-operative palpation revealed an axillary sentinel node in the remaining 18 patients. SPECT/CT showed the exact anatomical location of all visualised sentinel nodes.

CONCLUSION

SPECT/CT discovered 'hidden' sentinel nodes in the majority of patients with non-visualisation, but was less valuable in patients with only extra-axillary lymphatic drainage on the planar images. Exploration of the axilla in patients with persistent non-visualisation improved the identification of axillary (involved) sentinel nodes.

Quality of life after sentinel lymph node biopsy or axillary lymph node dissection in stage I/II breast cancer patients: a prospective longitudinal study

Background

Breast cancer patients’ quality of life (QoL) after surgery has been reported to improve significantly over time. Little is known about QoL recovery after sentinel lymph node biopsy (SLNB) in comparison to axillary lymph node dissection (ALND).

Methods

175 of 195 stage I/II breast cancer patients completed the EORTC QLQ-C30: one day before surgery (T0) and after 6 (T1), 26 (T2), 52 (T3) and 104 (T4) weeks. Of these, 54 patients underwent SLNB, 56 SLNB+ALND and 65 ALND. General linear models and paired T-tests between T0–T4 and T1–T4 were computed. Complications, radiotherapy and systemic therapy were added to the model.

Results

Significant time effects were found on physical, role and emotional functioning. Physical and role functioning decreased between T0 and T1. At T4, SLNB patients’ functioning had increased to their T0 level; ALND (+/– SLNB) patients’ functioning had increased, but had not improved to T0 level. Emotional functioning increased linearly between T0 and T4. At T4, emotional functioning was significantly higher in all groups as compared with T0. No significant group or interaction (time × group) effects were found. Complications and chemotherapy had a significant negative effect on role, emotional and cognitive functioning. Complications had a significant effect on social functioning also. Effect sizes varied between 0.00 and 0.06.

Conclusion

Two years post surgery, breast cancer patients’ QoL is comparable to that shortly before surgery. Women rated their emotional functioning as even better. SLNB is not associated with a better QoL than ALND. However, undergoing systemic therapy and/or experiencing complications affects QoL negatively.

Risk of invasion and axillary lymph node metastasis in ductal carcinoma in situ diagnosed by core-needle biopsy

Background

The aim of the study was to assess the risk of invasion and axillary lymph node metastasis in patients with ductal carcinoma in situ (DCIS) diagnosed by preoperative core-needle biopsy. The data were used to select criteria for patients in whom sentinel node (SN) biopsy might be indicated.

Methods

One hundred and seventy-one women with 172 DCIS lesions diagnosed by core-needle biopsy were analysed. Axillary staging was performed by SN biopsy, axillary node sampling, or level 1–2 axillary lymph node dissection.

Results

Invasive breast cancer was found in the surgical specimens from 45 tumours (26·2 per cent). Risk factors for invasion were a palpable lesion (odds ratio (OR) 2·95 (95 per cent confidence interval 1·20 to 7·26); P = 0·019), presence of a mass on mammography (OR 3·06 (1·43 to 6·56); P = 0·004), and intermediate (OR 5·81 (1·18 to 28·57); P = 0·030) or poorly differentiated (OR 5·46 (1·17 to 25·64); P = 0·031) tumour grade. Lymph node metastases were found in ten women with DCIS and invasion on final pathology. Factors associated with metastases were age 55 years or less (P = 0·030), invasion of 1·0 cm or more (P < 0·001) and the presence of vascular invasion (P = 0·001).

Conclusion

SN biopsy should be considered in women with an initial diagnosis of DCIS on core-needle biopsy who are at risk for invasion; this includes women with a palpable lump, a mass on mammography, and intermediate or poor tumour grade.

Introduction of sentinel node biopsy and stage migration of breast cancer

AIM

The purpose of this study was to examine in a large population based group of breast cancer patients treated in a regular care setting whether the introduction of the Sentinel Node Biopsy (SNB) led to detection of a higher percentage of patients with positive regional lymph nodes.

METHODS

The study includes 3665 early breast cancer patients, aged 30-85 years, diagnosed in the period 1997-2002 and registered at the Regional Cancer Registry of the Comprehensive Cancer Centre Middle Netherlands. During this period the SNB was introduced. The outcome of staging was compared for groups staged with or without SNB. A logistic regression model was used to adjust for age, calendar period and tumour size.

RESULTS

Overall a quarter of all patients over the period 1997-2002 underwent a SNB as method of lymphatic staging. The use of SNB clearly increased over time: from 2% in 1998 to 65% in 2002. The percentage node positive patients also rose significantly; before introduction of the SNB 30% of all patients were diagnosed with positive lymph nodes, and after SNB introduction this percentage was 40%. The increase is largely explained by the increase of patients diagnosed with only micrometastases. Adjustment did not change the results.

CONCLUSION

In conclusion, introduction of the SNB in early breast cancer led to significant upstaging of breast cancer patients treated in a regular care setting, due to the detection of more micrometastases. Since the relevance of micrometastases for long term survival is not yet known, this upstaging potentially led to over treatment of patients. On the other side, for some patients axillary lymph node dissection was prevented by the SNB procedure, preventing comorbidity.

Long term treatment related upper limb morbidity and quality of life after sentinel lymph node biopsy for stage I or II breast cancer

BACKGROUND

In a prospective study, long term upper-limb morbidity, perceived disabilities in activities of daily life (ADL) and quality of life (QOL) were assessed before and 2 years after sentinel lymph node biopsy (SLNB) or axillary lymph node dissections (ALND) for breast cancer.

METHODS

Two hundred and four patients with stage I/II breast cancer, mean age 55.6 years (SD: 11.6) entered the study and 181 patients (89%) could be evaluated after 2 years. Fifty-seven patients underwent SLNB (31%) and 124 patients underwent an ALND (69%). Assessments included pain, shoulder range of motion, muscle strength, arm volume, perceived shoulder disability in ADL and QOL.

RESULTS

Significant (P<0.05) changes between before and 2 years after surgery were found in almost all assessments of shoulder function, ADL and several QOL subscales. Patients in the ALND group showed significant more changes in range of motion (ROM), grip strength, arm volume, ADL and QOL physical- and role functioning, pain and sleeplessness and arm symptoms compared to the SLNB group. Multivariate linear regression analysis showed that ALND could predict decrease of ROM, grip strength, ADL and physical functioning (QOL) and increase of arm volume, pain and arm symptoms score (QOL). Radiation on the axilla predicts an additional decrease in shoulder ROM and increase of arm volume.

CONCLUSION

Two years after surgery for breast cancer, patients show significantly less treatment related upper limb morbidity, perceived disability in ADL and worsening of QOL after SLNB compared with ALND.

Using the intraoperative hand held probe without lymphoscintigraphy or using only dye correlates with higher sensory morbidity following sentinel lymph node biopsy in breast cancer: a review of the literature

BACKGROUND

There are no studies that have directly investigated the incremental reduction in sensory morbidity that lymphoscintigraphy images (LS) and triangulated body marking or other skin marking techniques provide during sentinel lymph node biopsy (SLNB) compared to using only the probe without LS and skin marking or using only dye. However, an indirect assessment of this potential for additional sensory morbidity reduction is possible by extracting morbidity data from studies comparing the morbidity of SLNB to that of axillary lymph node dissection.

METHODS

A literature search yielded 13 articles that had data on sensory morbidity at specific time points on pain, numbness or paresthesia from SLNB that used radiotracer and probe or used only dye as a primary method of finding the sentinel node (SN). Of these, 10 utilized LS, while 3 did not utilize LS. By matching the data in studies not employing LS to the studies that did, comparisons regarding the percentage of patients experiencing pain, numbness/paresthesia after SLNB could be reasonably attempted at a cutoff of 9 months.

RESULTS

In the 7 studies reporting on pain after 9 months (> 9 months) that used LS (1347 patients), 13.8% of patients reported these symptoms, while in the one study that did not use LS (143 patients), 28.7% of patients reported these symptoms at > 9 months (P < 0.0001). In the 6 studies reporting on numbness and/or paresthesia at > 9 months that used LS (601 patients), 12.5% of patients reported these symptoms, while in the 3 studies that did not use LS (229 patients), 23.1% of patients reported these symptoms at > 9 months (P = 0.0002). Similar trends were also noted for all these symptoms at < or = 9 months.

CONCLUSION

Because of variations in techniques and time of assessing morbidity, direct comparisons between studies are difficult. Nevertheless at a minimum, a clear trend is present: having the LS images and skin markings to assist during SLNB appears to yield more favorable morbidity outcomes for the patients compared to performing SLNB with only the probe or performing SLNB with dye alone. These results are extremely pertinent, as the main reason for performing SLNB itself in the first place is to achieve reduced morbidity.

Treatment-related upper limb morbidity 1 year after sentinel lymph node biopsy or axillary lymph node dissection for stage I or II breast cancer

BACKGROUND

In a prospective study, upper limb morbidity and perceived disability/activities of daily life (ADLs) were assessed before and 1 year after sentinel lymph node biopsy (SLNB) or axillary lymph node dissection (ALND).

METHODS

A total of 204 patients with stage I/II breast cancer (mean age, 55.6 years; SD, 11.6 years) entered the study, and 189 patients (93%) could be evaluated after 1 year. Fifty-eight patients (31%) underwent only SLNB, and 131 (69%) underwent ALND. Assessments performed before surgery (t(0)) and 1 year after surgery (t(1)), included pain, shoulder range of motion, muscle strength, upper arm/forearm circumference, and perceived shoulder disability/ADL.

RESULTS

Considerable treatment-related upper limb morbidity was observed. Significant (P < .05) changes between t(0) and t(1) were found in all assessments except strength of elbow flexors. Patients in the ALND group showed significantly more changes in the range of motion in forward flexion, abduction, and abduction/external rotation; grip strength and strength of shoulder abductors; circumference of upper arm and forearm; and perceived shoulder disability in ADLs compared with the SLNB group. Multivariate linear regression analysis showed that ALND could predict a decrease of range of motion in forward flexion, abduction, strength of shoulder abductors, grip strength, and shoulder-related ADLs and an increase in the circumference of the upper arm. Radiation of the axilla (19 patients) predicts an additional decrease in shoulder range of motion.

CONCLUSIONS

One year after treatment of breast cancer, there is significantly less upper limb morbidity after SLNB compared with ALND. ALND is a predictor for upper limb morbidity.

Detection of metastases in sentinel lymph nodes of breast cancer patients by multiple mRNA markers

Disseminated breast tumour cells in sentinel lymph nodes (SNs) were evaluated by quantitative real-time PCR and the sensitivity of this assay was compared to the routine histological analysis. First, several candidate marker genes were tested for their specificity in axillary lymph nodes (ALN) of 50 breast cancer patients and 43 women without breast cancer. The marker gene panel selected, designed to detect the mRNA of CK19, p1B, EGP2 and SBEM, was subsequently applied to detect metastases in 70 SNs that were free of metastases as determined by standard histological evaluation. Remarkably, seven negative SNs showed increased marker gene expression, suggesting the presence of (micro) metastases. Four of these seven SNs positive by real-time PCR proved to contain tumour deposits after careful review of the slides or further sectioning of the paraffin-embedded material. In three PCR positive SNs, however, no tumour cells were found by haematoxylin and eosin staining (H&E) and immunohistologically analysis. The quantitative real-time PCR assay with multiple mRNA markers for the detection of disseminated breast cancer cells in SNs thus resulted in an upstaging of SNs containing metastastic disease of 10% compared to the routine histological analysis. The application of this technique may be of clinical relevance, as it is suggested that micrometastatic disease in SNs are associated with further nodal non-SN metastases in breast cancer.

Detection of micrometastatic breast cancer by means of real time quantitative RT-PCR and immunostaining in perioperative blood samples and sentinel nodes

The aim of our study was to detect micrometastatic breast cancer by epithelial glycoprotein-2 (EGP-2) and cytokeratin 19 (CK19), using immunostaining and real time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). Fifty-eight breast cancer patients, 52 primary tumors, 75 sentinel nodes (SN) and 149 peripheral blood (PB) samples (from before, during and 4 days after operation) were examined. Immunostaining was performed with antibodies directed against EGP-2 and CK19. Detection limits were one Michigan Cancer Foundation-7 (MCF-7) breast cancer cell line cell/2.10(6) leukocytes (immunostaining) and one MCF-7 cell/10(6) leukocytes qRT-PCR. Control noncancer lymph nodes (n = 10) showed nonspecific CK19 staining, but were qRT-PCR negative; control healthy volunteer PB (n = 11) was always negative. Primary tumor samples, all positive with immunostaining, showed a wide variation of EGP-2 (>10(4) fold) and CK19 mRNA expression (>10(3) fold). SN (n = 19) from 16 patients were tumor-positive with routine haematoxylin-eosin (H&E) and/or immunostaining. SN tumor presence was positively correlated to qRT-PCR expression, but 3 tumor-positive SN were false negative with qRT-PCR. Three SN were qRT-PCR positive, while tumor negative with H&E and/or immunostaining. No immunostaining positive PB was observed, but 19 patients (33%) had one or more qRT-PCR positive PB samples. We concluded that primary tumors have varying expressions of EGP-2 and CK19 mRNA. Both markers can be used in qRT-PCR to obtain adequate sensitivity for single tumor cell detection. In SN, immunostaining appears more sensitive/specific than H&E or qRT-PCR for tumor detection. No immunostaining positivity was found in PB, while 33% of patients had qRT-PCR positive PB. The clinical value of these findings will have to be clarified.

Short-term morbidity of the upper limb after sentinel lymph node biopsy or axillary lymph node dissection for Stage I or II breast carcinoma

BACKGROUND

The goals of sentinel lymph node biopsy (SLNB) are to improve axillary staging and reduce unnecessary axillary lymph node dissections (ALND), thereby reducing treatment-related upper-limb morbidity. In the current prospective study, short-term upper-limb morbidity was assessed after SLNB and/or ALND.

METHODS

The study comprised 204 patients with Stage I/II breast carcinoma. Mean patient age was 55.6 years (standard deviation, 11.6). Sixty-six patients (32%) underwent SLNB only, and 138 (68%) underwent a Level I-II ALND. Assessment (preoperative [t0] and 6 weeks postoperative [t1]) included evaluation of shoulder range of motion, muscle strength, grip strength, pain, upper/forearm circumference, shoulder disability, and activities of daily life (ADL).

RESULTS

Considerable treatment-related upper-limb morbidity was observed. Significant (P < 0.001) changes were found for pain, range of motion in forward flexion, abduction and abduction/external rotation, strength of shoulder abductors and elbow flexors, and in perceived disability in ADL. However, no significant difference in change of upper-limb function and ADL was found between the SLNB and ALND groups.

CONCLUSIONS

Significant short-term treatment-related upper-limb morbidity exists after SLNB or ALND. There is no significant difference in short-term treatment-related morbidity between SLNB and ALND.

How many cases are enough for accreditation in sentinel lymph node biopsy in breast cancer?

BACKGROUND

There is considerable argument concerning the number of sentinel node biopsy cases with axillary dissection that surgeons should perform before they are eligible on abandoning axillary dissection in negative sentinel node patients.

DATA SOURCES

Papers that (1) address directly or indirectly the subject of credentialing or of learning curve, (2) report on a surgeon's performance, (3) are reported as feasibility or learning curve studies, or both, (4) discuss the learning curve issue, and (5) express an expert's opinion on the learning curve.

CONCLUSIONS

The number of procedures of the learning curve can not be fixed for all surgeons. Only surgeons in specialized breast cancer centers can succeed in meeting current recommendations with 20 to 30 cases. Surgeons from affiliated community hospitals will need more than 30 cases, whereas broad-based surgeons might need as many as 60 cases with their current caseload. Not all surgeons will be able to offer the procedure to their patients by the current recommendations.

Lymphatic mapping with tracer administration into the primary breast cancer

There is an ongoing debate over the best tracer injection technique in lymphatic mapping for breast cancer. The technique of low tracer volume administration into the primary breast cancer is presented. The reasons that led to this approach are explained as well as its advantages. Excision of radioactivity that remains at the injection site in the breast cancer prevents the gamma ray scatter that may hamper retrieval of a sentinel node. The intralesional injection technique avoids potential injection of tracer fluid across a lymphatic watershed, it enables identification of extra-axillary sentinel nodes and allows probe-guided excision of non-palpable tumours.

Will we need lymph node dissection at all in the future?

Traditionally in the treatment of primary breast cancer, axillary lymph node dissection (ALND) plays an important role. However, a substantial and increasing percentage of patients appear to have no nodal involvement and have been subjected to ALND unnecessarily. The first reason to perform an ALND is axillary nodal staging. After reviewing the literature, it can be concluded that in clinically node-negative patients an adequately conducted lymphatic mapping by sentinel node procedure is equal to ALND for this purpose. The second reason to perform an ALND is to establish the extent of nodal involvement, which might have an impact on adjuvant treatment recommendations. However, there is no evidence available that patients with extensive nodal involvement (= 4 positive nodes) benefit more from adjuvant systemic treatment (either standard or high dose) in terms of reduction of odds of recurrence and mortality compared to patients with limited nodal involvement and optimally administered so-called standard adjuvant treatment. The third reason to perform an ALND is to ensure axillary tumor control. Reviewing the different treatment options, it can be concluded that in clinically node-negative patients axillary control after axillary radiotherapy appears to be similar to axillary control after ALND. In clinically overt axillary involvement, ALND (with or without adjuvant radiotherapy) may result in an improved regional control. In the near future, ALND will not be the standard of care but will be reserved for those patients with proven axillary lymph node involvement. In microscopic disease, radiotherapy may be an alternative with equal control and less morbidity.

Frozen section investigation of the sentinel node in malignant melanoma and breast cancer

BACKGROUND

Intraoperative frozen section investigation allows immediate regional lymph node dissection when the sentinel node contains tumor. The purpose of this study was to determine the sensitivity of frozen section diagnosis of the sentinel node in melanoma and breast cancer patients.

METHODS

A total of 177 sentinel nodes from 99 melanoma patients and 444 lymph nodes from 262 breast cancer patients were assessed by frozen section investigation. Nodes were bisected, and a complete cross-section was obtained for frozen section. Step sections at three levels were made of the remaining lymphatic tissue and were stained with hematoxylin and eosin and S100/HMB45 (melanoma) or CAM5.2 (breast cancer) to obtain a final pathological diagnosis.

RESULTS

Frozen section investigation revealed metastases in 8 of 17 node-positive melanoma patients (47%). Seventy-one of 96 breast cancer patients (74%) with lymph node metastases were identified with frozen section. The specificity was 100% and 99%, respectively.

CONCLUSION

The sensitivity of intraoperative frozen section investigation of sentinel nodes was 47% in melanoma patients and 74% in breast cancer patients. Frozen section examination allows immediate axillary lymph node dissection in the majority of node-positive breast cancer patients. Frozen section analysis is not recommended in patients with melanoma.

Clinical relevance of sentinel lymph nodes outside the axilla in patients with breast cancer

BACKGROUND

Lymphatic mapping in patients with breast cancer can reveal sentinel lymph nodes that are not located at level I-II of the axilla. Little is known about the clinical relevance of these nodes.

METHODS

Some 113 consecutive patients with clinical stage T1-3 N0 M0 breast cancer were studied. Based on preoperative lymphoscintigraphy, sentinel node biopsy was performed guided by a gamma probe and patent blue dye. All sentinel nodes that were visible on lymphoscintigraphy were sought. Pathological examination of the sentinel nodes included step-sections and staining with CAM 5. 2. Axillary node dissection was performed regardless of sentinel lymph node status.

RESULTS

Twenty-one (19 per cent) of 113 patients had sentinel lymph nodes outside level I-II of the axilla, mostly in the internal mammary chain. Twenty-two of the 30 sentinel nodes at these sites were harvested. Three patients had sentinel nodes only outside the axilla. Four other patients had metastases outside the axilla. This changed postoperative treatment in three patients. No postoperative complication occurred.

CONCLUSION

Sentinel lymph nodes outside level I-II of the axilla were present in 19 per cent of patients with breast cancer in this series. Biopsy of these nodes was technically demanding but was performed without additional morbidity. The clinical impact was limited; treatment changed in only 3 per cent. Presented to the 52nd annual meeting of the Society of Surgical Oncology in Orlando, Florida, USA, March 1999 and the First International Congress on the Sentinel Node in Diagnosis and Treatment of Cancer in Amsterdam, The Netherlands, April 1999, and published in abstract form as Eur J Nucl Med 1999; 26(Suppl): S71

Sentinel node biopsy in breast cancer

The concept of breast sentinel node biopsy is based on the assumption that a breast cancer that metastasizes through the lymphatics will initially reach one or a few nodes in the corresponding lymph basin. The status of this or these sentinel node(s) will predict the status of all the other nodes in the basin. The sentinel node can be found stained blue or as being radioactive by injecting blue dye or a radioactive tracer around the tumour. Scintigraphy may further help to localize the sentinel node. The feasibility of the method has been validated by several studies comparing the status of the sentinel node with the node status of the axilla revealed by subsequent axillary clearance. Detection rates of 66-100% and false-negative rates of 17-0% have been reported. Before the method can be accepted for clinical use, a consensus concerning the accepted false-negative rate has to be reached and has to be shown in practice. From a theoretical point of view, a calculated false-negative risk rate of 2-3% can be accepted.