Radioguided sentinel node biopsy to avoid axillary dissection in breast cancer

The false-negative rate of sentinel node biopsy in patients with breast cancer: a meta-analysis

BACKGROUND

In sentinel node surgery for breast cancer, procedural accuracy is assessed by calculating the false-negative rate. It is important to measure this since there are potential adverse outcomes from missing node metastases. We performed a meta-analysis of published data to assess which method has achieved the lowest false-negative rate.

METHODS

We found 3,588 articles concerning sentinel nodes and breast cancer published from 1993 through mid-2011; 183 articles met our inclusion criteria. The studies described in these 183 articles included a total of 9,306 patients. We grouped the studies by injection material and injection location. The false-negative rates were analyzed according to these groupings and also by the year in which the articles were published.

RESULTS

There was significant variation related to injection material. The use of blue dye alone was associated with the highest false-negative rate. Inclusion of a radioactive tracer along with blue dye resulted in a significantly lower false-negative rate. Although there were variations in the false-negative rate according to injection location, none were significant.

CONCLUSIONS

The use of blue dye should be accompanied by a radioactive tracer to achieve a significantly lower false-negative rate. Location of injection did not have a significant impact on the false-negative rate. Given the limitations of acquiring appropriate data, the false-negative rate should not be used as a metric for training or quality control.

SPECT/CT scans allow precise anatomical location of sentinel lymph nodes in breast cancer and redefine lymphatic drainage from the breast to the axilla

BACKGROUND

Historical studies of lymphatic drainage of the breast have suggested that the lymphatic drainage of the breast was to lymph nodes lying in the antero-pectoral group of nodes in the axilla just lateral to the pectoral muscles. The purpose of this study was to confirm this is not correct.

METHODS

The hybrid imaging method of SPECT/CT allows the exact anatomical position of the sentinel lymph node (SLN) in the axilla to be documented during pre-operative lymphoscintigraphy (LS) in patients with breast cancer. We have done this in a series of 741 patients. The Level I axillary nodes were defined as anterior, mid or posterior. This was related to the anatomical location of the primary cancer in the breast.

RESULTS

A SLN was found in the axilla in 97.8% of our patients. Just under 50% of SLNs located in the axilla were not in the anterior group and lay in the mid or posterior group of Level I axillary nodes. There was a SLN in a single node field in 460 patients (63%), two node fields in 261(36%), three node fields in 6 and four node fields in 1 patient.

CONCLUSION

Axillary lymphatic drainage from the breast is not exclusively to the anterior (or antero-pectoral) group of Level I nodes.

SYNOPSIS

SPECT/CT lymphoscintigraphy shows that the breast does not always drain to the anterior group of Level I lymph nodes in the axilla but may drain to the mid axilla and/or posterior group in about 50% of patients with breast cancer regardless of the location of the cancer in the breast. These data redefine lymph drainage from the breast to axillary lymph nodes.

Is intraoperative imprint cytology evaluation still feasible for the evaluation of sentinel lymph nodes for lobular carcinoma of the breast?

BACKGROUND

The evaluation of sentinel lymph nodes (SLNs) from a patient with lobular breast cancer is challenging. Metastatic lobular cancer is difficult to identify in SLNs because of its low-grade cytomorphology and its tendency to resemble lymphocytes. Intraoperative imprint cytology (IIC) is a rapid, reliable method for evaluating SLNs intraoperatively. We sought to reexamine our experience with this technique in the identification of invasive lobular breast cancer SLN metastases.

METHODS

A retrospective review of a prospectively maintained database of IIC results of 1010 SLN mapping procedures for breast cancer was performed. From this cohort we reviewed SLN cases of lobular cancer. The SLNs were evaluated intraoperatively by bisecting the SLN. Imprints were made of each cut surface and stained with hematoxylin and eosin (H&E) and Diff-Quik. Permanent sections were evaluated with up to 4 H&E-stained levels and cytokeratin immunohistochemistry. IIC results were compared with final pathologic results.

RESULTS

A total of 67 cases of pure invasive lobular cancer were identified. The sensitivity was 71%, specificity was 100%, and accuracy was 92%. No statistically significant differences in sensitivity, specificity, or accuracy were identified between the intraoperative detection of lobular carcinoma vs ductal carcinoma. The specificity has remained the same since 2004. However the accuracy (82% vs 92%; P = .09) and sensitivity (52% vs 71%; P = .02) has improved since 2004.

CONCLUSIONS

As we have previously shown, the sensitivity and specificity of IIC in evaluating lobular carcinoma is feasible and accurate. IIC continues to be a viable alternative to frozen section for intraoperative evaluation.

Intraoperative assessment of sentinel lymph nodes in breast cancer

Background

Sentinel lymph node biopsy (SLNB) reduces the morbidity of axillary clearance and is the standard of care for patients with clinically node-negative breast cancer. The ability to analyse the sentinel node during surgery enables a decision to be made whether to proceed to full axillary clearance during primary surgery, thus avoiding a second procedure in node-positive patients.

Methods

Current evidence for intraoperative sentinel node analysis following SLNB in breast cancer was reviewed and evaluated, based on articles obtained from a MEDLINE search using the terms ‘sentinel node’, ‘intra-operative’ and ‘breast cancer’.

Results and conclusion

Current methods for evaluating the sentinel node during surgery include cytological and histological techniques. Newer quantitative molecular assays have been the subject of much recent clinical research. Pathological techniques of intraoperative SLNB analysis such as touch imprint cytology and frozen section have a high specificity, but a lower and more variably reported sensitivity. Molecular techniques are potentially able to sample a greater proportion of the sentinel node, and could have higher sensitivity.

Sentinel lymphnode biopsy in early breast cancer using methylene blue dye and radioactive sulphur colloid - a single institution Indian experience

BACKGROUND

Axillary lymph node dissection is an established procedure in breast cancer staging. However, it is associated with unpleasant side effects. A promising alternative to assess axillary lymph node status in early breast cancer patients is Sentinel Lymph Node Biopsy (SLNB). Isosulfan blue has traditionally been the dye used to identify the Sentinel Lymph Node (SLN). This article is a validation study of SLNB using methylene blue dye and radioactive sulphur colloid in early breast cancer Indian patients. MATERIALS #ENTITYSTARTX00026;

METHODS

With written informed consent, 100 patients with cytology or biospy proven carcinoma breast, clinical stage T1/ T2 N0 M0, underwent SLNB using combination of methylene blue dye & radioactive technetium 99m sulphur colloid as a part of validation study from June 2003 to February 2006. After validation study, from March 2006 to February 2007, 35 patients have undergone SLNB followed by complete axillary clearance in only those patients with SLNB being positive for metastases.

RESULTS

In all 100 patients of the validation study SLN was identified. Total number of cases with positive axillary nodes was 27, out of which SLN was only positive node for metastases in 69% of cases. The overall sensitivity, specificity, positive predictive valve and negative predictive valve of SLNB 96.2%, 100%, 100% and 98.6% respectively with false negative rate of 3.7%. In subsequent 35 patients who underwent SLNB followed by complete axillary clearance, SLNs was identified in all the cases.

CONCLUSIONS

SLNB is effective in early breast cancer patients of Indian population. SLNB using combination of methylene blue dye and radio-active Tc99m sulphur colloid can stage the axilla with high accuracy & low risk of false negativity in early breast cancer patients.

Isotope labelling and axillary node harvesting strategies for breast cancer

AIMS

The objective of this study was to assess the value of superficial (intradermal) and paratumoral (above the tumor) (ID) injection of labeled colloids for imaging sentinel lymph nodes (SLN) as a rescue technique in breast cancer patients for whom deep (intraparenchymatous) and peritumoral (around the tumor) (IP) injections had failed.

METHODS

We assessed data from 2 groups of women: 469 women for whom IP injections successfully visualized a SLN (IP-only) and 52 women for whom IP injections were unsuccessful and ID injection was performed (IP0-ID). Patient characteristics and SLN results were compared.

RESULTS

Most characteristics of the two patients series were similar. However, IP0-ID patients were on average 10years older than the IP-only patients and had more grade-III tumors. The false negative rate (FNR) for the IP0-ID patients (9/25, 23.8%) was significantly higher than for the IP-only patients (12/240, 5%; p<0.01) and for a subgroup of IP-only patients older than 50 years (8/159, 5%; p=0.009). Four of five false negatives in the IP0-ID group involved a tumor in the outer quadrants. The FNR for cases with external tumors was 33% for the IP0-ID patients, a percentage significantly higher than the corresponding values for the IP-only patients (5.8%) and for the IP-only patients older than 50 years (5.7%).

CONCLUSION

In patients with unsuccessful deep IP injections, superficial ID injections lead to a high percentage of false negative SLN conclusions, merely when tumours were located in the outer quadrants. Thus, it is recommended that patients with unsuccessful intra-parenchymatous and peritumoral injections of radiocolloids for tumors in outer quadrants undergo complete axillary dissection.

Sentinel lymph node mapping for primary breast cancer

The tumor status of the axillary lymph nodes is the single most important predictor of survival for patients with primary breast cancer. Because of its essential role in staging, regional control, and perhaps survival, axillary lymph node dissection (ALND) has long been the standard of care for patients with operable breast cancer. During the past decade, the introduction and development of sentinel lymph node dissection (SLND) for primary breast cancer have allowed surgeons to determine the tumor status of the axilla without a standard level I and II ALND. Several well-designed studies have documented that SLND is an effective way of assessing axillary nodal status with minimal morbidity and high accuracy. We address the current status and future directions of SLND for primary breast cancer.

Lower and central tumor location correlates with lymphoscintigraphy drainage to the internal mammary lymph nodes in breast carcinoma

BACKGROUND

Radiation to the internal mammary chain (IMC) may be indicated for breast carcinoma patients with positive axillary sentinel lymph nodes (SLNs) and lymphoscintigraphic evidence of drainage to the IMC. The purpose of this study was to identify predictors of IMC drainage in patients with positive axillary SLNs.

METHODS

The records of 297 breast carcinoma patients with positive axillary SLNs and preoperative lymphoscintigraphy were reviewed between 1995 and 2002. Radiolabeled colloid was injected peritumorally with lymphoscintigraphy performed 30-60 minutes later. Drainage to the regional nodes of 279 patients was seen on lymphoscintigraphy. Associations among patient and tumor-related factors and drainage to the IMC were examined.

RESULTS

Drainage to the IMC on lymphoscintigraphy was seen in 63 patients (21%). IMC drainage only occurred in 4 patients, and 59 patients had both axillary and IMC drainage. The only variable that correlated with IMC drainage was tumor location (P = 0.017). Rates of drainage to the IMC were 14.1% for upper outer quadrant (n = 128), 16.7% for upper inner quadrant (n = 30), 31.6% for lower outer quadrant (n = 19), 42.9% for lower inner quadrant (n = 14), and 28.4% for central tumors (n = 88). IMC drainage rates differed significantly between upper and lower tumors (lower 36.4% vs. central 28.4% vs. upper 14.6%, P = 0.003) but not between medial and lateral tumors (medial 25.0% vs. central 28.4% vs. lateral 16.3%, P = 0.077).

CONCLUSIONS

Patients with tumors in the lower or central breast and positive axillary SLNs have increased incidence of drainage to the IMC. Preoperative lymphoscintigraphy can help to define the nodal basins at risk for harboring disease.

Intraoperative frozen section examination of axillary sentinel lymph nodes in breast cancer

The study presents the results from intraoperative frozen section assessment of axillary sentinel lymph nodes (SLNs) in breast cancer. Routine histological frozen sections from one level were used, two sections stained with haematoxylin and eosin. Immunohistochemistry for cytokeratins was applied to the permanent SLN paraffin sections only. Axillary dissection was performed on all SLN-positive cases regardless of the size of the metastatic deposits. With a detection rate of 83%, 272 patients entered the study over a period of 46 months. A total of 61 cases were SLN positive by frozen section analysis. The paraffin sections gave an additional 23 SLN-positive cases. The false-negative rate for frozen sections was then 27% (23/84). Micrometastases were found in 28 of 84 cases, and macrometastases in 56. The false-negative rate of frozen sections for micrometastases was 71% (20/28), and for macrometastases 5% (3/56). A total of 73% (61/84) of the patients underwent axillary surgery as a one-step procedure.

Intraoperative cytologic examination of breast sentinel lymph nodes: test utility and patient impact

The sentinel lymph node (SLN) procedure is a method for ascertaining the axillary lymph node status in patients with breast cancer. Intraoperative examination of the SLN may be important, because a positive result directs surgery to a complete axillary lymph node dissection. Intraoperative cytologic examination (IOCE) is a method of intraoperative evaluation, although little data are available regarding the sensitivity of the method with respect to tumor size and the size of the SLN metastasis. All SLN cases for the years 1997-2002 at Magee-Womens Hospital were tabulated for primary breast carcinoma size, IOCE result, final histologic result, and size of the SLN metastasis. All SLNs had IOCE with touch imprints. Scrape SLN preparations and frozen sections were strongly discouraged. There were 748 SLN cases comprising 1576 SLNs that had IOCE, and there were 247 true positive SLN cases comprising 522 SLNs. Of the 247 true positive SLN cases, 111 had a positive IOCE (111/247; 45% sensitivity overall) and there were 136 false negatives. Of the 247 cases, 164 were SLN micrometastases < or =2.0 mm in size, and 44 (27%) of these were detected by IOCE, while the remaining 120 cases were false negative. Of the 83 SLN macrometastases (>2.0 mm), 66 (80%) were detected by IOCE, with 17 false negatives. In this series, 15 cases (2%) were given the IOCE diagnosis of atypical/defer, and all of these permanent sections were histologically positive. There were five IOCE-positive cases that were histologically negative. Of the 164 SLNs with micrometastases < or =2.0 mm, 17.6% (29/164) were < or =0.5 mm (6/29 [21.4%] were IOCE positive), 5.5% (9/164) were 0.51-1.0 mm (3/9 [33%] were IOCE positive), and 3.6% (6/164) were 1.1-2.0 mm (2/6 [33%] were IOCE positive). There were 83 SLNs with macrometastases larger than 2.0 mm, and 66/83 (80%) were detected by IOCE. In this group, 22% (18/83) were 2.1-5.0 mm (8/18 [44.4%] were IOCE positive) and 57.8% (48/83) were larger than 5.0 mm (41/48 [85%] were IOCE positive). The mean primary breast tumor size was 15.4 mm, with a mean SLN tumor size of 1.4 mm. There was a significant correlation with tumor size and the presence of SLN metastasis, and a significant correlation with tumor size and size of the SLN metastasis. There was a significant t correlation of primary tumor size and positive IOCE, with the group of negative IOCE cases having a mean tumor size of 14 mm and the positive IOCE group having a mean tumor size of 22 mm. The overall sensitivity of the method was 45%, specificity 99%, positive predictive value 0.99, and negative predictive value 0.80. Sensitivity of the IOCE procedure based on SLN tumor size is as follows: < or =0.5 mm, 21.4%; 0.51-1.0 mm, 33%; 1.1-2.0 mm, 33%; 2.1-5.0 mm, 44.4%; and >5.0 mm, 85%. Primary tumor size correlates with a positive SLN status and size of the SLN metastasis. Most false-negative IOCEs are due to micrometastases. Positive IOCE cases had a significantly larger SLN metastasis size (mean 8.0 mm) than the false-negative IOCE group (mean 1.4 mm). The IOCE of SLNs has a high negative predictive value, but this is a poor test for the detection of micrometastases, as this group accounts for the majority of false-negative IOCEs of breast SLNs.

Significance of metastasis detected by molecular techniques in sentinel nodes of patients with gastrointestinal cancer

The clinical significance of micrometastasis in sentinel nodes (SNs) may differ in various organs. In particular, the prognostic value of SN micrometastases detected by reverse transcriptase-polymerase chain reaction (RT-PCR) is still controversial. We investigated the diagnostic and therapeutic significance of nodal molecular metastasis detected by nested RT-PCR for cytokeratin (CK) 19 mRNA in gastrointestinal cancer. In 51 cases with GI tract cancer treated by standard curative resection, SNs were identified by a radio-guided method. In 10 of 51 patients, 25 SNs and 3 non-SNs were histologically negative and RT-PCR positive. Three non-SNs with positive CK19 mRNA were randomly sampled from the same basin where histologically positive SNs were identified. Immunohistochemical analysis of six additional step sections obtained at 30- micro m intervals with use of an anticytokeratin antibody showed clearly recognizable histological metastases in 4 of 25 histologically negative/RT-PCR-positive SNs (16%). In one case of esophageal squamous cell carcinoma with nodal micrometastasis identified by CK19 RT-PCR, extranodal local recurrence in the SN basin (left supraclavicular basin) was observed 6 months postoperatively. These findings suggest that nodal micrometastasis detected by nested RT-PCR has some clinical significance in GI cancer. Molecular assessment of the SN may be a valuable tool to complement routine histological examination for GI cancers.

False-negative frozen section of sentinel lymph node biopsy for breast cancer

A prospective study is presented of frozen section examinations (FS) performed in parallel with 265 consecutive sentinel lymph node procedures (SLNP) over a 20-month period. The final pathological study included immunohistochemistry (IHC) for keratin if the haematoxylin-eosin (HE)-stained section was tumour free. FS correctly identified node-positive or node-negative axillae in 235 cases. In 28 SLNPs the final examination gave a positive result not detected in the FS, resulting in reoperation. In 21 of these false-negative (FN) cases micrometastases (MIM) were present. There were no false-positive cases, but in two cases of lobular carcinoma the findings in the FS were equivocal, the final reports recording metastases in one but not in the other. Lobular carcinoma and other less common subtypes of carcinoma were overrepresented, ductal carcinoma not otherwise specified (NOS) being less likely to affect the FN findings.

Intraoperative imprint cytologic evaluation of sentinel lymph nodes for lobular carcinoma of the breast

BACKGROUND

The evaluation of sentinel lymph nodes (SLNs) from a woman with lobular cancer of the breast is frequently challenging. Intraoperative imprint cytology (IIC) is equivalent to frozen sectioning for rapid SLN evaluation and is advantageous because it is rapid, reliable, cost-effective, and conserves tissue. Metastatic lobular carcinoma is difficult to identify in SLN because of its low-grade cytomorphology, its tendency to infiltrate lymph nodes in a single cell pattern, and because individual cells can resemble lymphocytes. We are unaware of any large published studies, using any technique, to evaluate SLN for lobular carcinoma.

METHODS

A retrospective review of the intraoperative imprint cytology results of 678 SLN mapping procedures for breast carcinoma was performed. From this cohort, we studied SLN from cases of lobular carcinoma. These SLN were evaluated intraoperatively by either bisecting or slicing the SLN into 4-mm sections. Imprints were made of each cut surface and stained with hematoxylin and eosin and/or Diff-Quik. Permanent sections were evaluated with up to 4 hematoxylin and eosin-stained levels and cytokeratin immunohistochemistry. IIC results were compared with final histologic results.

RESULTS

Sixty-one cases of pure invasive lobular carcinoma were identified. Sensitivity was 52%, specificity was 100%, accuracy was 82%, negative predictive value was 78%. No statistically significant differences in sensitivity, specificity or accuracy were identified for the intraoperative detection of lobular carcinoma versus ductal carcinoma. The sensitivity for detecting macrometastases (more than 2 mm) was better than for detecting micrometastases, 73 versus 25%, respectively (P = 0.059).

CONCLUSIONS

The sensitivity and specificity of IIC are similar to that of intraoperative frozen section evaluation. Therefore, IIC is a viable alternative to frozen sectioning when intraoperative evaluation is required. If SLN micrometastasis is used to determine the need for further lymphadenectomy, more sensitive intraoperative methods will be needed to avoid a second operation.

Role of imprint cytology in the intraoperative evaluation of sentinel lymph nodes for malignant melanoma

Controversy exists over the utility of different methods for intra-operative sentinel lymph node (SLN) evaluation in patients with malignant melanoma (MM). The aim of this study was to evaluate the role of intra-operative imprint cytology (IC) in patients with MM. 215 SLNs from 99 patients with MM were examined by IC and results compared with the results of permanent sections. 24 patients had MM deposits in their SLNs and this was confirmed by histological examination. Intraoperative IC was positive in 11 of these patients (46% sensitivity). In addition, there were three false-positive IC diagnoses (79% positive predictive value); one of these was due to contamination during the sectioning of the SLN. The specificity and the negative predictive values of the IC were 96 and 85%, respectively. IC is a valuable method of intra-operative SLN evaluation which can spare approximately half of the patients with clinically occult regional metastases from a second surgical procedure. However, special care must be taken to avoid false-positive results due to contamination.

Logistics of referral, diagnostic assessment and treatment of patients with breast symptoms and signs

BACKGROUND AND AIMS

The logistics of diagnosis and treatment in a hospital with slightly above 400 new cases of breast cancer per year is analysed.

MATERIALS AND METHODS

The patient flow from referral, through the diagnostic procedures and through surgical treatment is described.

RESULTS AND CONCLUSIONS

The basic principle of the diagnostic assessment is the triple diagnostic procedure including mammography supplemented by ultrasonography, fine needle aspiration cytology and clinical examination. The radiologist and pathologist are working together in the breast diagnostic centre and are thus able to give a "single visit diagnosis" in most cases. The surgeon sees the patient either the same day or the next. A "consensus meeting" held each week with representatives for all specialities present has an important function in quality assurance and education. If one or more of the triple diagnostic components reach conclusion level "suspicious lesion", surgery is indicated. In hospital management is based on day surgery for all biopsies, wide excisions with or without sentinel node and some ablatio simplex mammae. For wide excision and ablation with complete axillary node clearance, the patients are transferred from the day surgery unit to a patient hotel after 3-4 hours of observation and stay till the drain can be removed. Only in rare case of high cardiopulmonary risk, beds in ordinary wards are used. This is a highly cost efficient logistic saving the hospital approximately 400,000 EUR a year compared to ordinary in hospital treatment.

Palpable breast carcinomas: a hypothesis for clinically relevant lymphatic drainage in sentinel lymph node biopsy

Previous studies have shown that independent of tumor size, palpable breast tumors have a higher incidence of lymph node metastasis compared with nonpalpable tumors. This study further examines this phenomenon using a large sentinel lymph node (SLN) database. Data from a prospective, institutional review board (IRB)-approved, multi-institutional study from the University of Louisville Breast Cancer Sentinel Lymph Node Study Group was used. From August 1997 through December 2001, 3192 patients with clinical T1 and T2 N0 breast cancer underwent SLN biopsy, most with a combined technique of radioactive colloid and blue dye, followed by level I/II axillary dissection. Patients with palpable tumors tended to be younger (mean age 58 years) compared with nonpalpable tumors (mean age 61 years). The incidence of positive axillary metastasis was significant between palpable and nonpalpable tumors (43% and 23%, respectively), independent of tumor size by logistic regression (p = 0.0001). The SLN identification rate was significantly different between palpable and nonpalpable tumors (95% versus 91%, respectively; p < 0.0001). A unifying theory to explain the phenomenon that palpable tumors, stage for stage, are associated with a higher rate of nodal metastasis is that palpable tumors are, on average, closer to the skin and the rich network of dermal lymphatics. We believe that the dermal lymphatics of the breast represent a clinically relevant metastatic pathway to the axilla.

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.

Intraoperative analysis of sentinel lymph nodes by imprint cytology for cancer of the breast

BACKGROUND

The utilization of lymphatic mapping techniques for breast carcinoma has made intraoperative evaluation of sentinel lymph nodes (SLN) attractive, because axillary lymph node dissection can be performed during the initial surgery if the SLN is positive. The optimal technique for rapid SLN assessment has not been determined. Both frozen sectioning and imprint cytology are used for rapid intraoperative SLN evaluation.

METHODS

A retrospective review of the intraoperative imprint cytology results of 133 SLN mapping procedures from 132 breast carcinoma patients was performed. SLN were evaluated intraoperatively by bisecting the lymph node and making imprints of each cut surface. Imprints were stained with hematoxylin and eosin (H&E) and Diff-Quik. Permanent sections were evaluated with up to four H&E stained levels and cytokeratin immunohistochemistry. Imprint cytology results were compared with final histologic results.

RESULTS

Sensitivity and specificity of imprint cytology were 56% and 100%, respectively, producing a 100% positive predictive value and 88% negative predictive value. Imprint cytology was significantly more sensitive for macrometastasis than micrometastasis 87% versus 22% (P = 0.00007). Of 13 total false negatives, 11 were found to be due to sampling error and 2 due to errors in intraoperative interpretation. Both intraoperative interpretation errors involved a diagnosis of lobular breast carcinoma.

CONCLUSIONS

The sensitivity and specificity of imprint cytology are similar to that of frozen section evaluation. Imprint cytology is therefore a viable alternative to frozen sectioning when intraoperative evaluation is required. If SLN micrometastasis is used to determine the need for further lymphadenectomy, more sensitive intraoperative methods will be needed to avoid a second operation.

Impact of non-axillary sentinel node biopsy on staging and treatment of breast cancer patients

The purpose of this study was to evaluate the occurrence of lymphatic drainage to non-axillary sentinel nodes and to determine the implications of this phenomenon. A total of 549 breast cancer patients underwent lymphoscintigraphy after intratumoural injection of (99m)Tc-nanocolloid. The sentinel node was intraoperatively identified with the aid of intratumoural administered patent blue dye and a gamma-ray detection probe. Histopathological examination of sentinel nodes included step-sectioning at six levels and immunohistochemical staining. A sentinel node outside level I or II of the axilla was found in 149 patients (27%): internal mammary sentinel nodes in 86 patients, other non-axillary sentinel nodes in 44 and both internal mammary and other non-axillary sentinel nodes in nineteen patients. The intra-operative identification rate was 80%. Internal mammary metastases were found in seventeen patients and metastases in other non-axillary sentinel nodes in ten patients. Staging improved in 13% of patients with non-axillary sentinel lymph nodes and their treatment strategy was changed in 17%. A small proportion of clinically node negative breast cancer patients can be staged more precisely by biopsy of sentinel nodes outside level I and II of the axilla, resulting in additional decision criteria for postoperative regional or systemic therapy.

A selection algorithm for internal mammary sentinel lymph node biopsy in breast cancer

Internal mammary lymph-node (IMN) metastases in breast carcinomas have a major influence on survival, comparable with the influence of axillary lymph-node metastases (ALNM). Prospective, randomized trials have demonstrated that complete IMN dissection as part of extended radical mastectomy does not improve overall or disease-free survival. In the subset of patients with tumours 1cm or less in size and no ALNM, information on IMN status would provide important information. In these cases, the presence of IMN metastases would change the staging from stage I to stage IIIB, according to the current tumour, node and metastasis classification. More importantly, it would influence these patients' adjuvant treatment. Lymphatic mapping for sentinel lymph-node (SLN) biopsy has demonstrated extra-axillary drainage in up to 35% of patients. Recent reports have demonstrated the feasibility of internal mammary sentinel lymph-node (IM-SLN) biopsy. Here we review the general prognostic and clinical significance of tumor location and lymph-node metastases in breast cancer and discuss the specific factors associated with IMN identification, metastases and treatment in the pre-SLN and SLN eras. Based on our review, we propose an algorithm for a selective approach to IM-SLN in breast cancer.

Indium-111-octreotide scintigraphy, intraoperative gamma-detector localisation and somatostatin receptor expression in primary human breast cancer

12 women with primary breast cancer underwent somatostatin receptor scintigraphy (SRS) with 111In-DTPA-D-Phe1-octreotide. The tumour sizes varied between 2 and 5 cm and were all, except one, palpable at clinical examination. Tumour biopsies were taken with additional sampling from normal breast tissue, fat, muscle, axillary lymph nodes and peripheral blood. Ratios between the 111In activity concentration in the tissue biopsies (Ti) and in peripheral blood (B) as well as in normal breast tissue (Br) were calculated. In 8/12 patients the scintillation detector was used intraoperatively for radioactivity measurements of the biopsies in situ and ex vivo. The sstr-subtype profiles were determined by northern blot analysis and the relative expression of sstr2 by ribonuclease protection assay (RPA) and immunocytochemistry. Preoperative SRS visualised all primary breast cancer tumours. The scintigraphic image showed no correlation with the histopathological type of the tumour or with the abundance of oestrogen/progesterone receptors on the tumour. Two patients with a massive tumour infiltration of the lymph nodes had a distinct positive SRS of the ipsilateral axilla. In one patient with three nodal metastases the scintigraphic image of the axilla was weak but visible. Four other patients with a negative axillary scintigraphy had 1-2 lymph node metastases. The Ti/B ratios for the breast tumours varied between four and 33 and were not different from Ti/Br ratios. In lymph node metastases the Ti/B ratios were higher (10-41). Intraoperative detector measurements showed a significant difference between the breast tumour and normal tissue in 2/8 patients in situ. Similar measurements on excised tissues (ex vivo) showed a significant difference in 6/8 patients. Two patients with lymph node metastases exhibited a significantly increased uptake ex vivo by detector measurements, but in only one of them in situ. All tumour biopsies expressed the presence of sstrl, 3, 4 and 5, but not of sstr2 at northern analysis. On the other hand, sstr2 was detected in all tumours by RPA and immunocytochemistry. Preoperative SRS visualised primary breast cancer lesions in all 12 patients. SRS could also demonstrate extensive axillary tumour infiltration. Intraoperative use of the scintillation detector could not exclude axillary metastases in situ. The low Ti/B values of both primary tumours and metastases indicate limitations of the radiopharmaceutical used.

Intraoperative evaluation of sentinel lymph nodes for breast carcinoma: current methodologies

Sentinel lymph node biopsy is an important new addition to the surgical management of patients with breast carcinoma. Sentinel nodes have a higher chance of containing metastases than do nonsentinel nodes. Sentinel lymph node biopsy provides an opportunity to stage breast carcinoma patients more accurately and to modify subsequent treatment. One of the most exciting current roles of sentinel lymph node biopsy is the ability to stage patients intraoperatively, allowing a one-step axillary lymph node dissection if the sentinel lymph node contains metastatic carcinoma. Currently, intraoperative evaluation of sentinel lymph nodes is performed using imprint cytology with or without rapid cytokeratin staining, frozen sectioning with or without rapid cytokeratin staining, scrape preparations, or some combination of these techniques. We review the relative strengths and weaknesses of these different methodologies. A great deal of controversy exists regarding the management of patients with metastatic breast carcinoma, particularly those patients with occult and micrometastatic disease. These issues are beyond the scope of this article.

Sentinel node biopsy for breast cancer: does the number of sentinel nodes removed have an impact on the accuracy of finding a positive node?

BACKGROUND AND OBJECTIVES

The number of sentinel lymph nodes (SLNs) removed during biopsy may have an impact on the accuracy of finding a positive SLN. This study investigated various factors to determine if they had any significant correlation with the number of SLNs found during biopsy. In patients with positive SLNs, the nodes were then analyzed to determine which SLN contained metastasis.

METHODS

For 263 patients with breast cancer who successfully underwent SLN biopsy, parameters such as tumor size, histologic characteristics, differentiation, and receptor status, patient age, breast quadrant, type of surgery, mapping with blue dye only or with radiocolloid, and whether biopsy was performed before or after tumorectomy were prospectively collected. These factors were analyzed to determine whether they had any significant correlation to the number of removed lymph nodes. Positive SLNs were ranked in the order they were removed and examined for which node contained the metastasis.

RESULTS

During biopsy, a mean of 1.8 (range, 1-5) SLNs were found. The SLNs were negative in 158 patients and positive in 105. The number of SLNs removed was comparable between node-negative and node-positive patients, and none of the parameters analyzed was significantly related to the number of SLNs removed. Of the 105 patients with a positive SLN, the first SLN independently predicted the pathologic status of the axilla in 96 patients (91.4%; 95% CI 86.1-96.8), and the first and second SLN independently predicted the status in 104 patients (99%; 95% CI 97.2-100). Only one of 105 patients had metastasis in the third SLN removed.

CONCLUSION

The pathologic status of the axilla was independently determined by removal of the first or first and second SLN in 99% of patients; removal of more than three SLNs did not increase the accuracy of finding a positive node.

Comparison of vital dye-guided lymphatic mapping and dye plus gamma probe-guided sentinel node biopsy in breast cancer

The optimal technique for sentinel lymph node biopsy (SLNB) is still debated. SLNB with peritumoral injection of Patent blue dye was performed in 129 clinically T1-T2 and N0 breast cancers in 127 patients (group A); it was later replaced by combined dye and radiocolloid-guided SLNB preceded by lymphoscintigraphy in 72 breast cancer patients (group B). This study compares these two methods. All patients underwent completion axillary dissection. Means of 1.4 and 1.3 SLNs were identified in groups A and B, respectively. The mean number of non-SLNs for the whole series was 14.9 (range 5-42). The first 53 cases of lymphatic mapping (dye only) comprised the institutional learning period during which the identification rate of at least 1 SLN in 30 consecutive attempts reached 90%. The identification rate for the subsequent 76 group A patients was 92%. The accuracy rate of SLNBs for overall axillary nodal status prediction and the false-negative rate for group A patients (after excluding the learning-phase cases) were 93% and 10%, respectively. All 72 group B cases had at least one SLN identified, and only one false-negative case occurred in this group (accuracy and false-negative rates of 99% and 3%, respectively). Both the dye-only and the combined SLNB methods are suitable for SLN identification, but the latter works better and results in higher accuracy, a higher negative predictive value, and a lower false-negative rate. It is therefore the method of choice.

Value of frozen-section analysis of sentinel lymph nodes for primary cutaneous malignant melanoma

OBJECTIVE

To analyze a large, single-institution experience with routine frozen section (FS) of the sentinel lymph node (SLN) in patients with primary cutaneous melanoma.

SUMMARY BACKGROUND DATA

Controversy exists over the utility of intraoperative FS analysis of the SLN in patients with primary cutaneous melanoma.

METHODS

All patients with clinically node-negative cutaneous melanoma undergoing SLN biopsy from 1991 to 1999 were identified from a prospective database. All SLNs were examined by FS. Step-sectioning and immunohistochemistry of permanent section were performed for SLNs negative by FS.

RESULTS

At least one SLN was identified in 98% (360/368) of patients. There were 74 (20%) SLNs positive on permanent section; FS was positive in 59% of these. The accuracy, sensitivity, and specificity of FS were 92%, 59%, and 100%. Because isolated recurrence developed in six patients in the nodal basin in which the SLN was negative, the failure rate was 1.7%. The false-negative rate for SLN biopsy was 7.5%.

CONCLUSIONS

Because the prevalence of metastases within the SLN and sensitivity of FS analysis are low, routine use of FS for all patients undergoing SLN biopsy is not recommended.

Utility of intraoperative frozen section analysis of sentinel lymph nodes in breast cancer

BACKGROUND

Intraoperative frozen section pathologic analysis of sentinel lymph node (SLN) may guide immediate (single-stage) completion axillary dissection for patients with nodal metastases.

METHODS

The results of 203 consecutive patients undergoing SLN biopsy who had intraoperative pathology consultation between January 1998 and September 2000 were reviewed. SLN were analyzed by standard frozen section procedures. Final pathologic analysis included hematoxylin and eosin (H&E) staining of serial sections at 2-mm intervals.

RESULTS

Frozen section analysis correctly identified a positive or negative result in 185 of 203 cases (overall accuracy 91%). In 17 of 53 cases, the SLNs were negative for tumor by frozen section, but positive on permanent section analysis (sensitivity 68%). The mean size of the nodal metastases was 6.2 mm and 1.5 mm in patients found to have true positive and false negative results, respectively (P <0.003). A single false positive SLN is reported.

CONCLUSIONS

Two thirds of the patients were spared the need for reoperative axillary lymphadenectomy.

The problem of the accuracy of intraoperative examination of axillary sentinel nodes in breast cancer

BACKGROUND

Sentinel node (SN) biopsy has become accepted as a reliable method of predicting the state of the axilla in breast cancer. The key issue, however, is the accuracy of the pathological evaluation of the biopsied node, which should be done intraoperatively whenever possible.

METHODS

In our initial experience on 192 patients using a conventional intraoperative frozen section method, the false-negative rate was 6.3%, and the negative predictive value was 93.7%. We devised a new and exhaustive intraoperative method, requiring about 40 minutes, in which pairs of sections are taken every 50 microm for the first 15 sections and every 100 microm thereafter, sampling the entire node. Sentinel node metastases were found in 143 of the 376 T1N0 cases examined (38%).

RESULTS

Metastases were always identified on hematoxylin and eosin sections, although in 4% of cases, cytokeratin immunostaining on adjacent sections was useful for confirming malignancy. In 233 patients the SNs were disease-free; of these patients, 222 had metastasis-free axillary nodes, and 11 (4.7%) had another metastatic node.

CONCLUSION

Extensive intraoperative examination of frozen sentinel nodes correctly predicts an uninvolved axilla in 95.3% of cases (negative predictive value). This method is, therefore, suitable for identifying patients in whom axillary dissection can be avoided.

Internal mammary lymph nodes and sentinel node biopsy in breast cancer

The long-term follow-up of patients treated with extended radical mastectomy has proved that the internal mammary node (IMN) status is an important prognosticator of breast cancer. Patients with isolated IMN involvement seem to have the same outcome as those with limited axillary disease, and these patients may therefore be overstaged in the TNM system. Sentinel node biopsy (SNB) of IMNs may be an ideal staging procedure, but lymphatic mapping studies demonstrate that data from extended radical mastectomy series cannot be extrapolated to patients suitable for SNB, where the IMN involvement is <5% overall, and around 1% for IMN metastases without axillary disease. Current evidence does not allow internal mammary SNB to be recommended as a standard procedure, but as patients with IMN involvement may benefit from adjuvant systemic treatment, internal mammary SNB should be further studied in this context.

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.

Usefulness of 99m-Tc-sestamibi scintimammography in suspected breast cancer and in axillary lymph node metastases detection

AIMS

To evaluate the usefulness of 99m-Tc-sestamibi scintimammography (SSM) in the detection of T1-2, N0-1, M0 breast cancer (BC) and axillary node (AN) metastases.

PATIENTS AND METHODS

A series of 239 women (median age 55 years) who had already been selected for breast biopsy underwent both mammography (MG) and SSM before surgery. The final diagnosis confirmed in 207 (86.6%) patients, and benign breast lesions in 32 (13.4%).

RESULTS

Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of MG and SSM in BC detection were 88.9% vs 87.9%, 62.5% vs 93.8% (P<0.01), 93.9% vs 98.9%, 46.5% vs 54.5%, and 85.4% vs 88.7%, respectively. Age did not affect (P=NS) SSM sensitivity, and in premenopausal patients (n=80 (33.5%)) its specificity was 100%. Overall sensitivity and specificity of SSM for assessing AN involvement were 82.3% and 94.1%, respectively. In patients with <3 AN metastases (n=33 (53.2%)) SSM sensitivity was 69.7%, and only one out of six patients with a single AN metastasis had a positive scan.

CONCLUSIONS

In patients with suspicious MG undergoing biopsy, SSM should be considered before surgery because of its high specificity, especially in younger patients. At present, its usefulness in detection of AN metastases is still modest and does not allow a correct pre-operative staging of patients with BC.

Anatomy and physiology of lymphatic drainage of the breast from the perspective of sentinel node biopsy

Knowledge of the anatomy and physiology of the lymphatic system is helpful when considering a particular sentinel node biopsy technique. The delicate balance between internal and external pressures in a lymphatic channel can be influenced by the injection volume and by massage in a negative or positive way. The narrow openings in the interendothelial junctions determine the speed of clearance of particles with a certain size, and this has implications for the timing of lymphoscintigraphy and surgery. Tracer uptake and lymph flow are highly variable and depend on a number of factors, some of which are beyond our control. The lymphatic anatomy is not completely understood despite numerous studies since the end of the 18th century. Several topics have been elucidated in more recent studies and through experience with sentinel node biopsy. First, although axillary drainage is the principal lymphatic path of the breast, any drainage pattern from any quadrant of the breast can occur. Second, most lymph from the breast flows to the nodal basins with a direct course, not passing through the subareolar plexus. Another relevant point is that gentle massage encourages lymph flow and facilitates sentinel node detection. What problems do we still face in clinical practice? The optimum size and number of labeled colloid particles remain to be established. The optimum volume of the tracer also remains to be determined. But the main controversy concerns the injection site. Although the intradermal injection technique has attractive practical features, there is currently insufficient certainty that drainage of tracer injected anywhere in or underneath the skin of the breast reflects drainage from the cancer. Connections between collecting lymphatic vessels from the tumor site and the collecting vessels from the skin and subdermal lymphatics can explain the concordance between intraparenchymal and superficial injections in most patients. To determine the technique that yields the best sentinel node identification rate with the lowest possible false-negative rate would require a large randomized trial with all patients undergoing a complete lymph node dissection and evaluation of all other axillary lymph nodes with serial sections and immunohistochemistry. Current knowledge about sensitivity is based on examination of the other axillary nodes with hematoxylin and eosin staining and not with immunohistochemistry, with the exception of two studies. (33,76) In addition, a complete level I to III dissection may not have been done in all patients, and it is not certain that pathologists removed and examined all the nodes from the specimens. The proposed study seems impossible now that routine axillary node dissection has been abandoned by the larger centers around the world. Choosing the most attractive approach requires determining the aim of lymphatic mapping. A superficial injection technique may be adequate when the purpose is to spare patients without lymph node metastases in the axilla an unnecessary axillary node dissection. An intraparenchymal injection technique should be used when the additional purpose is to determine the stage as accurately as possible and to identify sentinel nodes elsewhere.

Preoperative lymphoscintigraphy during lymphatic mapping for breast cancer: improved sentinel node imaging using subareolar injection of technetium 99m sulfur colloid

BACKGROUND

Preoperative lymphoscintigraphy has been recommended to confirm the successful uptake and direction of migration of radiotracer into sentinel nodes during lymphatic mapping for breast cancer. In addition, preoperative lymphatic mapping may provide a visually useful aid to the relative location of sentinel nodes within a nodal basin. One common method of breast lymphoscintigraphy involves injections of unfiltered technetium 99m sulfur colloid (Tc-99m-SC) directly into parenchymal tissues surrounding a tumor or biopsy cavity (IP injection). Because of the many imaging failures and prolonged imaging times of IP lymphoscintigraphy, the procedure has fallen into disfavor by oncologic surgeons. The purpose of this study is to document the increased success rate of preoperative breast lymphoscintigraphy using a new anatomic site of injection, the subareolar lymphatic plexus (SA injection).

STUDY DESIGN

In the 12 months between December 1, 1998, and December 29, 1999, 42 women with stage I and II breast cancer underwent preoperative lymphoscintigraphy by either the IP (n = 12, December 1998 to May 1999) or SA (n = 30, May 1999 to December 1999) route of injection. Both groups were injected with 1 mCi (37 MBq) of unfiltered Tc-99m-SC followed immediately by external gamma-camera imaging. The success rate for preoperative sentinel node imaging and the total imaging time were recorded in both groups.

RESULTS

The success rate of identifying a sentinel node by SA lymphoscintigraphy was 90% (n = 27 of 30 patients), compared with 50% (n = 6 of 12 patients) for IP lymphoscintigraphy (p = 0.009). The imaging time in the SA injection group was 34 +/- 16 minutes, which was 59% shorter than the imaging time in the IP injection group of 82 +/- 48 minutes (p < 0.001). No uptake into internal mammary nodes was seen in either group.

CONCLUSIONS

Moving the site of injection ofunfiltered Tc-99m-SC to the subareolar lymphatic plexus (SA injection) increased the success rate of preoperative lymphoscintigraphy to 90%, compared with 50% using IP injections. Preoperative SA lymphoscintigraphy resulted in the rapid visualization of axillary sentinel nodes within 30 minutes of SA injection, enabling a visual determination of the approximate number of sentinel nodes and their relative locations within the axilla. We conclude SA injection of unfiltered Tc-99m-SC is superior to IP injections when performing preoperative breast lymphoscintigraphy and is a visually useful aid to lymphatic mapping for breast cancer.