Current controversies in sentinel lymph node biopsy for breast cancer

New concept in selecting blue dye injection site effect on clinical outcome of early-stage breast cancer patients: a retrospective cohort

BACKGROUND

Clinico-anatomical review and pilot studies demonstrated that intraparenchymal injection at any site, even those not containing the index lesion, or periareolar injections should provide concordant outcomes to peritumoral injections.

METHOD

This was a single-center retrospective cohort at King Chulalongkorn Memorial Hospital. The electronic medical records of patients were characterized into conventional and new injection concept groups. The inclusion criteria were patients who had either a mastectomy or BCS along with SLNB. We excluded patients who underwent ALND, received neoadjuvant therapy, or had non-invasive breast cancer. The primary outcome was the 5-year rate of breast cancer regional recurrence. Additionally, we reported on the re-operation rate, disease-free period, distant disease-free period, mortality rate, and recurrence rates both locoregional and systemic. Recurrences were identified through clinical assessments and imaging.

SURGICAL TECHNIQUE

3 ml of 1%isosulfan blue dye was injected, with the injection site varying according to the specific concept being applied. In cases of SSM and NSM following the new concept, the blue dye was injected at non-periareolar and non-peritumoral sites. After the injection, a 10-minute interval was observed without massaging the injection site. Following this interval, an incision was made to access the SLNs, which were subsequently identified, excised, and sent for either frozen section analysis or permanent section examination.

RESULT

There were no significant differences in DFS, DDFS or BCSS between the two groups (p = 0.832, 0.712, 0.157). Although the re-operation rate in the NI group was approximately half that of the CI group, this difference was not statistically significant (p = 0.355).

CONCLUSION

Our study suggests that tailoring isosulfan blue dye injection site based on operation type rather than tumor location is safe and effective approach for SLN localization in early-stage breast cancer. However, this study has limitations, including being a single-center study with low recurrence and death cases. Future studies should aim to increase the sample size and follow-up period.

Tumor Contact With Internal Mammary Perforator Vessels as Risk Factor for Gross Internal Mammary Lymph Node Involvement in Patients With Breast Cancer

PURPOSE

The identification of internal mammary lymph node metastases and the assessment of associated risk factors are crucial for adjuvant regional lymph node irradiation in patients with breast cancer. The current study aims to investigate whether tumor contact with internal mammary perforator vessels is associated with gross internal mammary lymph node involvement.

METHODS AND MATERIALS

We included 297 patients with primary breast cancer and gross internal mammary (IMN+) and/or axillary metastases as well as 230 patients without lymph node metastases. Based on pretreatment dynamic contrast-enhanced magnetic resonance imaging, we assessed contact of the tumor with the internal mammary perforating vessels (IMPV).

RESULTS

A total of 59 patients had ipsilateral IMN+ (iIMN+), 10 patients had contralateral IMN+ (cIMN+), and 228 patients had ipsilateral axillary metastases without IMN; 230 patients had node-negative breast cancer. In patients with iIMN+, 100% of tumors had contact with ipsilateral IMPV, with 94.9% (n = 56) classified as major contact. In iIMN- patients, major IMPV contact was observed in only 25.3% (n = 116), and 36.2% (n = 166) had no IMPV contact at all. Receiver operating characteristic analysis revealed that "major IMPV contact" was more accurate in predicting iIMN+ (area under the curve, 0.85) compared with a multivariate model combining grade of differentiation, tumor site, size, and molecular subtype (area under the curve, 0.65). Strikingly, among patients with cIMN+, 100% of tumors had contact with a crossing contralateral IMPV, whereas in cIMN- patients, IMPVs to the contralateral side were observed in only 53.4% (iIMN+) and 24.8% (iIMN-), respectively.

CONCLUSIONS

Tumor contact with the IMPV is highly associated with risk of gross IMN involvement. Further studies are warranted to investigate whether this identified risk factor is also associated with microscopic IMN involvement and whether it can assist in the selection of patients with breast cancer for irradiation of the internal mammary lymph nodes.

Evaluation of learning curve with Indocyanine Green (IcG) versus blue dye for sentinel lymph node biopsy in breast cancer

BACKGROUND

Indocyanine green (IcG) is an alternative to isosulfan blue (IB) for sentinel lymph node (SLN) mapping in breast cancer (BC). IcG carries improved cost and safety, but oncologic data upon implementation in practice is limited. We evaluated the learning curve defined as oncologic yield and operative (OR) time for IcG in SLN mapping in BC.

METHODS

Retrospective review of patients >18 years with cTis-2 cN0 BC undergoing surgery first with SLN biopsy using IB or IcG. Analysis compared IB versus IcG across three time cohorts.

RESULTS

Of 278 patients, 77 received IB and 201 received IcG. OR time was longer for IcG (p ​= ​0.022). There was no difference in oncologic yield between groups (p ​= ​0.35, p ​= ​0.61).

CONCLUSIONS

Surgeons may be able to safely transition from IB to IcG for patients with early-stage breast cancer undergoing surgery first. Individuals should track their own data to confirm safety of the technique.

Internal mammary node involvement in patients with axilla-negative early breast cancer: a narrative review

Early breast cancer staging involves radiological and pathological evaluation of the tumour and regional lymph nodes. The internal mammary nodes (IMN) are an important site of possible metastasis and influence disease stage and prognosis. However, the recommendation for routine IMN assessment remains unclear. Internal mammary sentinel lymph node biopsy (SLNB) is associated with increased morbidity and an unknown survival benefit. Furthermore, the IMN are traditionally thought to be involved only synchronous with, or following, axillary node (AXN) metastasis. The aim of this review is to determine the prevalence of IMN metastasis in patients with axilla-negative early breast cancer. A narrative review of studies assessing IMN metastasis was performed. The literature search was completed using the database Medline (Ovid). Twenty-two retrospective studies were identified. The studies included data from SLNB, US, MRI, PET/CT and opportunistic biopsy during free-flap reconstruction (FFR). The prevalence of isolated IMN metastasis ranged from 1.2% to 17.9%.

Repeat Sentinel Lymph Node Surgery in Recurrent Breast Cancer: Peritumoral vs. Periareolar Injections

BACKGROUND

In the setting of recurrent cancer, there is no standard methodology regarding the technical aspects of repeat sentinel lymph node (rSLN) surgery. We analyzed our institutional experience with attempted rSLN surgery to determine the optimal injection technique.

MATERIALS AND METHODS

Single site, retrospective review of patients with prior lumpectomy for breast cancer who presented with recurrent or new ipsilateral breast cancer and underwent attempt at rSLN surgery from 2008 to 2017. Patients with prior mastectomy or no prior ipsilateral axillary operation were excluded.

RESULTS

A total of 141 patients were included; 103 (73%) underwent successful rSLN biopsy procedure. Lymphoscintigraphy showed aberrant drainage in 32 (26%). Periareolar (PA) injection resulted in failed mapping in 23/99 (23%) and aberrant drainage in 25/85 (29%). By comparison, peritumoral (PT) injection had a 14/38 (37%) incidence of failed mapping and 7/37 (19%) aberrant drainage (P = .11 and .23, respectively). Of the patients with successful sentinel lymph node (SLN) biopsy procedure via PA injection, 11/76 (14%) were positive for metastatic disease as compared with 2/24 (8%) in PT injection. Sixteen patients had lymph node metastases; 13 (81%) were SLNs, including 3 positive aberrant SLNs. Five-year regional recurrence rates were 11.4% (95% confidence interval, 0%-21.5%) and 0% for PA and PT injection techniques, respectively.

CONCLUSION

PA and PT injections had a similar incidence of SLN identification and aberrant drainage. Preoperative lymphoscintigraphy is beneficial in patients with recurrent breast cancer given the higher incidence of aberrant drainage in this population. Patients who underwent PA injections had a higher incidence of regional recurrences but this difference was not statistically significant.

[Risk of axillary recurrence after sentinel lymph node biopsy before neoadjuvant chemotherapy in breast cancer]

OBJECTIVES

In case of large breast cancer, neoadjuvant chemotherapy (NAC) can be performed to reduce the size of the tumor and thus perform a conservative surgery. The place of the sentinel lymph node biopsy (SLNB) in case of NAC is still debated. The main aim of this study is to assess the risk of axillary recurrence after negative SLNB before NAC.

METHODS

It is a retrospective, observational and uni-centric study. We included 18 to 80-year-old patients with unilateral breast cancer requiring a NAC and with a negative SLNB before NAC. Our primary endpoint was axillary recurrence.

RESULTS

Between August 2006 and October 2016, 64 patients had a negative GS performing before a NAC and did not benefit from axillary dissection after NAC. The average duration of follow-up was 37 months. During our follow-up, we did not find any cases of axillary recurrence.

CONCLUSION

This study supports the reliability of lymph node status assessment using the SLNB before CNA.

The effect of subareolar isosulfan blue injection on pulse oximeter readings

Besides several side effects including anaphylaxis, blue dyes are also known to cause false pulse oximeter readings. We aimed to examine the effects of subareolar isosulfan blue injection on pulse oximeter (SpO2) readings. The study group included 27 patients undergoing SLNB using both radiocolloid and isosulfan blue. Another group of 27 patients constituted the control group. Pulse oximeter readings were compared. SpO2 decline ≥4 % was defined as significant. All but one (96.2 %) of the patients in the study group showed SpO2 declines, compared to only one patient in the control group. Median ± Interqartile Range (IR) SpO2 decrease was 3.0 ± 4.0 % in the study and 0.0 ± 1.0 % in the control group (p < 0.001). There were significant (≥4 %) SpO2 decreases in 13 (48.1 %) patients in the study group. Statistically significant differences were noted between the two groups in all recordings between 15 and 180 min (p < 0.001). Initial time for SpO2 fall and the time to the lowest SpO2 recording were 10.0 ± 10.0 and 40.0 ± 30.0 min respectively. Using subareolar injection, the frequency of false readings is comparable with intraparenchymal injections, and is higher than intradermal injections. Time to peak SpO2 fall, and the recovery period, are delayed in the subareolar technique.

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.

Local and regional control in breast cancer: role of sentinel node biopsy

The development and acceptance of the SLND has profoundly affected the management of breast cancer. SLND has supplanted ALND as a highly accurate and less-morbid axillary staging procedure in patients with clinically node-negative early-stage breast cancer. SLND alone is associated with less than 1% isolated axillary recurrence in patients with node-negative disease and provides excellent regional nodal control. Historically, ALND has been the recommended treatment for patients with SLN metastases. ALND was thought to offer prognostic information, prevent axillary local recurrence, and possibly render a small survival benefit. However, resection of nonsentinel nodes with metastases may not affect survival, and not all axillary metastases progress to become clinically evident. Furthermore, with increased understanding of tumor biology, nodal status and number of involved lymph nodes are no longer the only determinants of systemic therapy. As improved breast cancer screening allows identification of early-stage disease localized to the breast, and because treatment plans are more often made on the basis of tumor biology, the role of completion ALND may be less critical. The low LRR rates seen in the ACOSOG Z0011 trial, several other randomized trials, and retrospective reviews suggest that SLND alone may provide adequate locoregional control and provide adequate information to guide adjuvant systemic therapy in selected women with clinically node-negative early-stage breast cancer.

Comparison of efficacy of Tc-99m HIG and Tc-99m nanocolloid on sentinel lymph node mapping in patients with breast cancer

BACKGROUND AND AIM

This study compared the effectiveness of Tc-99m human polyclonal immunoglobulin (HIG) and Tc-99m nanocolloid at detecting sentinel lymph nodes (SLNs) with lymphoscintigraphy and an intraoperative gamma-probe (IGP) in patients with early breast cancer.

METHODS

The study group consisted of 50 women; 25 patients each were given Tc-99m HIG or Tc-99m nanocolloid for lymphoscintigraphy. Then, intraoperative SLN localization with IGP was performed. The results of IGP, lymphoscintigraphy, blue dye injected just before surgery, and pathology were compared.

RESULTS

In the Tc-99m HIG group, one patient had tumours in both breasts. In two patients, we could not detect SLNs with lymphoscintigraphy, although they were detected with IGP and blue dye. We found SLNs for all tumours with IGP. With the intraoperative blue dye, SLNs were identified for 25 tumours; for one tumour, no SLN was detected with blue dye. In the histopathological examination, 13 tumours showed metastasis in the SLN and in 11 of these 13, there were also metastases in the axilla. One patient had a skip metastasis. In the Tc-99m nanocolloid group, SLNs were identified in 24 patients with lymphoscintigraphy. IGP found SLNs in 24 patients. The blue dye detected SLNs in all patients. On histopathological examination, 10 patients had metastasis in the SLN and there were also metastases in the axilla in all of these patients.

CONCLUSION

Tc-99m HIG can be used in SLN detection with preoperative lymphoscintigraphy and IGP in early-stage breast cancer patients.

Breast cancer treatment beliefs and influences among surgeons in areas of scientific uncertainty

BACKGROUND

Breast cancer treatment beliefs in areas of scientific uncertainty may contribute to widely variable practices. We sought to better describe surgeons' beliefs and to identify the relative importance of different information sources on surgeons' decision-making.

METHODS

A total of 2,188 American College of Surgeons (ACoS) members were surveyed on their treatment beliefs in 4 controversial areas and on the perceived influence of various information sources on their decision-making. Responses were analyzed by sex, practice type, oncology training, professional society membership, and breast cancer patient volume.

RESULTS

Nine hundred twenty-three responses were received, with 459 eligible for analysis. Responses diverged most regarding significance of positive sentinel lymph node biopsy (SNLB) and role of post-lumpectomy radiation for low-risk ductal carcinoma-in-situ (DCIS). Overall, expert opinion ranked as the most influential information source.

CONCLUSIONS

Axillary dissection after positive SLNB and post-lumpectomy radiation in low-risk DCIS denoted areas of greater uncertainty. Breast cancer opinion leaders have substantial influence when standard practice is uncertain.

Axillary sentinel lymph node biopsy after neoadjuvant chemotherapy for carcinoma of the breast

BACKGROUND

The timing and accuracy of axillary sentinel lymph node biopsy (SLNB) in patients who are receiving neoadjuvant chemotherapy (NACT) for breast cancer are controversial. To examine the accuracy of SLNB after NACT, the authors performed SLNB after chemotherapy on all of patients who received NACT at their institution starting in January 1997.

METHODS

Seventy-nine women who underwent NACT between 1997 and 2008 comprised this study and were divided as follows: 4 women had stage I disease, 60 women had stage II disease, and 15 women had stage III disease, including 10 women who had multicentric disease. Thirty-nine women (49.4%) had clinical evidence of axillary metastasis (N1-N2) at the time of diagnosis. The regimen, the duration of treatment, and the number of cycles of NACT depended on clinical response. The choice of breast conservation therapy or mastectomy was based on the patient's response to treatment and patient preference. All patients underwent SLNB after NACT.

RESULTS

Seventy-three patients underwent breast conservation therapy, and 6 patients underwent mastectomy. Sentinel lymph nodes were identified in 98.7% of patients (in 1 patient, SLNB failed to capture 1 proven axillary metastasis), and 29 patients underwent full axillary lymph node dissection. Fourteen patients (17.7%) had no residual carcinoma (invasive or ductal carcinoma in situ) in their breast, 5 patients (6.3%) had residual ductal carcinoma in situ (only), and 60 patients (75.9%) had residual invasive carcinoma. One false-negative SLNB was reported in the group of 23 patients who underwent full axillary dissection after a negative SLNB. No patient had a subsequent axillary recurrence.

CONCLUSIONS

SLNB after NACT was feasible in virtually all patients and accurately selected patients who required complete level I and II axillary dissection. NACT frequently downstaged the axilla, converting patients with N1-N2 lymph node status to N0 status and also avoiding full axillary dissection in these 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.

The lymphatic anatomy of the breast and its implications for sentinel lymph node biopsy: a human cadaver study

Background

Current understanding of the lymphatic system of the breast is derived mainly from the work of the anatomist Sappey in the 1850s, with many observations made during the development and introduction of breast lymphatic mapping and sentinel node biopsy contributing to our knowledge.

Methods

Twenty four breasts in 14 fresh human cadavers (5 male, 9 female) were studied. Lymph vessels were identified with hydrogen peroxide and injected with a lead oxide mixture and radiographed. The specimens were cross sectioned and radiographed to provide three dimensional images. Lymph (collecting) vessels were traced from the periphery to the first-tier lymph node.

Results

Lymph collecting vessels were found evenly spaced at the periphery of the anterior upper torso draining radially into the axillary lymph nodes. As they reached the breast some passed over and some through the breast parenchyma, as revealed in the cross-section studies. The pathways showed no significant difference between male and female specimens. We found also perforating lymph vessels that coursed beside the branches of the internal mammary vessels, draining into the ipsilateral internal mammary lymphatics. In some studies one sentinel node in the axilla drained almost the entire breast. In most more than one sentinel node was represented.

Conclusion

These anatomical findings are discordant with our current knowledge based on previous studies and demand closer examination by clinicians. These anatomical studies may help explain the percentage of false-negative sentinel node biopsy studies and suggest the peritumoral injection site for accurate sentinel lymph node detection.

Anatomopathological analysis of sentinel and nonsentinel lymph nodes in breast cancer: hematoxylin-eosin versus immunohistochemistry

The authors compare the detection of metastases in sentinel lymph nodes (SLNs) and nonsentinel lymph nodes (NSLNs) using hematoxylin-eosin (HE) staining versus immunohistochemistry (IHC). Thirty-six patients with breast carcinoma undergo exeresis of the primary tumor and of 50 SLNs and 491 NSLNs. Sentinel lymph nodes are sectioned into transverse slices of 2- to 3-mm thickness, and a cytologic smear and a frozen section were obtained from each slice. The slices are completely cut into serial sections at 100-microm intervals. Two consecutive 4-microm-thick sections are then obtained from each level and were prepared for HE staining and IHC. Nonsentinel lymph nodes are evaluated similarly to SLNs. The authors obtain 4076 SLN sections and 32 012 NSLN sections, for a total of 36 088 sections. A comparison of HE staining versus IHC based on the total number of sections shows a sensitivity of 93.8%, a negative predictive value of 98.9%, and an accuracy of 99.1%. The values obtained by HE staining are similar to those obtained by IHC.

Sentinel node identification rate, but not accuracy, is significantly decreased after pre-operative chemotherapy in axillary node-positive breast cancer patients

BACKGROUND

The aim was to prove the low identification rate of sentinel lymph node biopsy (SNB) and to determine the feasibility of replacing axillary lymph node dissection (AND) in axillary lymph node positive patients after chemotherapy.

METHODS

From October 2001 to July 2005, 875 consecutive patients with primary operable breast cancer underwent SNB and AND. Among them, 238 received pre-operative chemotherapy. We compared the identification rate, false negative rate (FNR), negative predictive value (NPV), and accuracy of SNB in clinically node-positive patients with or without chemotherapy.

RESULTS

The identification rate was significantly lower in patients received chemotherapy (77.6%) than in those not received it (97.0%) (P<0.001). In those received the therapy, the FNR was 5.6%, the NPV was 86.8%, and the accuracy was 95.9%. In those not received therapy, the FNR was 7.4% and the accuracy was 92.6% (differences not statistically significant).

CONCLUSION

The identification rate in confirmed axillary lymph node-positive patients was significantly lower in patients received pre-operative chemotherapy, but accuracy did not differ significantly between the two groups. Thus, for patients who achieve complete axillary clearance by chemotherapy, SNB could replace AND.

Locoregional therapy of breast cancer: maximizing control, minimizing morbidity

The goal of locoregional therapy in breast cancer has remained unchanged for a century: the eradication of all malignant cells from the breast and draining lymph nodes, hopefully prior to them having spread to distant organs. However, how we accomplish this goal has changed dramatically over this time period and our success in achieving this goal has been greatly enhanced by improvements in breast imaging and systemic therapies. The therapeutic importance of surgery and radiation has been underestimated in recent years and is thought to have minimal impact on long-term outcome. More recent data have reputed this contention and the relationship between local control and survival in breast cancer is becoming increasingly apparent. This article will review the importance of attaining optimum local control with minimum morbidity and examine where the future of locoregional therapy of breast cancer may lie.

Successful Internal Mammary Visualization With Periareolar Injections of Tc-99m Antimony Sulfur Colloid in Sentinel Node Breast Lymphoscintigraphy

PURPOSE

The subareolar and periareolar injection techniques result in higher detection rates and do not require tumor localization in impalpable lesions when compared with the peritumoral technique. One of the main criticisms, however, is the widely reported inability to detect internal mammary nodes. This contrasts with our clinical experience using Tc-99m antimony sulfur colloid, in which internal mammary nodes are commonly seen.

METHODS

A retrospective analysis of 241 patients over 38 months was performed to investigate the ability of our periareolar injection technique to detect internal mammary lymph node drainage in breast cancer sentinel node lymphoscintigraphy. Four injections of 5 to 10 MBq (0.14-0.27 mCi) Tc-99m antimony sulfur colloid were administered on the day of surgery followed by massage and imaging. The radioisotope was suspended in 0.1 mL with a 0.5-mL air lock. Each injection was performed over 2 seconds with a 25-gauge needle at a depth of 1.1 to 1.3 cm. Patients whose records could not be retrieved or who underwent an injection technique apart from periareolar or peritumoral were removed from the analysis.

RESULTS

One hundred thirty-three patients underwent the periareolar technique, 72 patients underwent the peritumoral technique, and 36 patients were excluded from the analysis. Internal mammary drainage was seen in 24 of 133 (18.0%) patients, of which 12 (9%) were seen only in the internal mammary chain. This is much higher than previous studies quoting 0.0% to 4.3% and is similar to previously reported rates using the peritumoral technique.

CONCLUSIONS

Our periareolar injection technique using Tc-99m antimony sulfur colloid is able to detect internal mammary lymph nodes in at least 18.0% of patients.

Clinical and Therapeutic Importance of Sentinel Node Biopsy of the Internal Mammary Chain in Patients with Breast Cancer: A Single-Center Study with Long-Term Follow-Up

BACKGROUND

We evaluated the incidence of sentinel lymph nodes (SLNs) in the internal mammary chain, calculated the lymphoscintigraphy and surgical detection rates, and evaluated the clinical effect on staging and the therapeutic approach in patients with breast cancer.

METHODS

The study involved 741 women diagnosed with breast cancer eligible for the SLN technique. Lymphoscintigraphy was performed on the day before the operation by peritumoral injection of (99m)Tc-labeled nanocolloid. During the operation, a gamma probe was used to detect the SLN, which was then removed.

RESULTS

A total of 719 SLNs were found in the axillary chain and 72 in the internal mammary chain. Preoperative lymphoscintigraphy showed 107 hot spots in the internal mammary chain, but only 72 SLNs in 65 patients were identified by the gamma probe and then removed with no complications. Of these 65 patients, 10 had a positive internal mammary chain SLN on final pathologic examination, whereas 55 patients had >or=1 negative SLNs on final pathologic analysis. Thirty-five (53%) of 65 patients had also an axillary SLN, but only 5 patients (8%) had a positive SLN on pathologic analysis.

CONCLUSIONS

Evaluation of the SLNs in the internal mammary chain may provide more accurate staging in breast cancer patients. If an internal mammary sampling is not performed, patients may be understaged. This technique may allow better selection of those patients who will be submitted to adjuvant locoregional radiotherapy.

Sentinel lymph node mapping using SPECT–CT fusion imaging in patients with oral cavity squamous cell carcinoma

Lymphoscintigraphic planar imaging is commonly performed to locate the sentinel lymph nodes (SLN) preoperatively. The images are, however, obscure lacking anatomical information and only rough topographical orientation of the SLNs is possible. Image fusion of Single Photon Emission Computed Tomography (SPECT) and Computed Tomography (CT) has been suggested to be an anatomically more precise method for preoperative SLN mapping. In the present study, preoperative lymphoscintigraphic SLN mapping was performed by using a hybrid gamma-camera with CT system (SPECT-CT) in addition to conventional planar lymphoscintigraphy in 15 consecutive patients with squamous cell carcinoma (SCC) of the oral cavity. The planar images were compared to fused SPECT and CT images. SPECT-CT fusion images showed only one SLN that was not detected in planar images. Two SLNs suspected in planar images could be excluded by SPECT-CT. The location of the SLNs could be determined more accurately by SPECT-CT. SPECT-CT fusion imaging was found feasible for preoperative SLN identification in patients with oral cavity SCC. It enables more accurate localisation of the SLNs, but it rarely reveals SLNs, that are not detected on planar images.

The prevention, detection, and management of breast cancer

The reduction in the incidence of contralateral breast cancer in women treated with adjuvant tamoxifen provided a model for prevention using endocrine agents. Oestrogen-receptor-positive cancer can be prevented with tamoxifen, but side effects limit its clinical utility, and the risk-benefit ratio is not sufficiently high to routinely recommend tamoxifen as a preventive agent. Agents being evaluated in prevention trials include raloxifene and the aromatase inhibitors; these are expected to be at least as effective as tamoxifen and to have fewer side effects. Core needle biopsy (providing histological information) and high-resolution breast ultrasound enhance preoperative assessment of breast cancer. Mammography remains the only screening test shown to reduce breast cancer deaths in randomised trials. Magnetic resonance imaging may have a role in screening women with inherited mutations of the breast cancer genes. Sentinel lymph node biopsy accurately assesses lymph node status and is associated with less morbidity than axillary dissection. Where the biopsy is negative (no histologic evidence of metastases), no further axillary treatment is necessary. Breast reconstruction after mastectomy can produce good cosmetic results, especially where autologous tissue is used. Myocutaneous flaps using latissimus dorsi or transverse rectus abdominus muscles are increasingly popular. Adjuvant trastuzumab therapy in patients whose tumours overexpress HER2 (growth factor receptor) can reduce recurrence rates and improve survival. Neoadjuvant endocrine therapy (as an initial treatment before surgery) is an underutilised treatment in postmenopausal women with oestrogen-receptor-positive large operable or locally advanced cancers. It makes more patients suitable for surgery and offers others the choice of breast conservation.

[EUSOMA requirements for breast cancer units in Spain]

INTRODUCTION

The optimal treatment of breast cancer consists of a multidisciplinary approach in specialized units, benefitting patients and leading to more rational resource use. Based on these premises, the European Society of Mastology (EUSOMA) drew up recommendations designed to provide all European countries with high-quality multidisciplinary teams.

MATERIAL AND METHOD

We present and analyze the results obtained from a survey of breast cancer units in 241 Spanish hospitals performed by the Breast Diseases Group of the Spanish Association of Surgeons.

RESULTS

Breast disease was treated in general surgery departments in 131 hospitals and Spanish surgeons showed strong interest in continuing training (41.2% had a postgraduate degree in mastology). Multidisciplinary discussions at weekly intervals took place in 95 hospitals (73.6%) hospitals for planning a diagnostic and therapeutic course of action specific for each patient. Written protocols for diagnosis and treatment were used in 119 departments (90.8%) and quality control measures were applied in 83 (63.4%).

CONCLUSIONS

We stress the need for mandatory requirements in Spain for breast cancer units, preferably adapted to the EUSOMA criteria, which are accepted by the relevant committee of the European Parliament. Through its Breast Diseases Group, the Spanish Association of Surgeons should be involved in accreditation standards for breast surgeons and should promote adequate specialization programs.

Implications of the sentinel lymph node procedure for local and systemic adjuvant treatment

PURPOSE OF REVIEW

The objective of the sentinel lymph node procedure in breast cancer is to perform an accurate axillary staging and provide good local control, while sparing the patients the morbidity of an axillary lymph node dissection. Since its routine clinical use, questions were raised concerning the implications for local and systemic adjuvant treatment. This review provides an update of the recent literature.

RECENT FINDINGS

As a result of a more detailed histopathologic work-up of the sentinel lymph node, higher rates of lymph node metastases are detected. This leads to an upstaging of a subset of node-negative patients and an increase in the overall percentage of node-positive patients. However, the clinical implications of micrometastases and isolated tumor cells remain unclear. Furthermore, sentinel lymph nodes may be found in the internal mammary lymph node chain but the treatment of these nodes is subject of debate.

SUMMARY

Current guidelines recommend axillary lymph node dissection in patients with a positive sentinel node. The surgical removal of the internal mammary lymph node is only indicated in the context of a clinical trial. Radiation therapy of the axilla is an acceptable alternative for patients who refuse an axillary lymph node dissection (clinical trial). The value of radiotherapy to the internal mammary lymph node has never been established. Systemic treatment decisions in patients with a macrometastasis or micrometastasis in the sentinel lymph node follow the guidelines of node-positive patients, whereas in patients with isolated tumor cells only, guidelines for node-negative patients are followed. The results of ongoing clinical trials will be important for the development of further guidelines.

Accuracy and reliability of sentinel node biopsy in patients with breast cancer. Single centre study with long term follow-up

The aim of our study is to evaluate the frequency of false-negative (FN) sentinel node procedures in patients with breast cancer. A total of 791 breast cancer patients underwent sentinel lymph node (SLN) biopsy at our institution between July 1997 and February 2005. A 2-day protocol was used to localise the sentinel node with the injection of 99mTc-nanocolloid. There were two phases in the study: the learning phase (50 patients) and the application phase (741 patients). In the learning phase, a complete lymphadenectomy was always performed. In the application phase, sentinel nodes were studied postoperatively with breast cancer and lymphadenectomy was performed when considered warranted by the pathological postoperative results. The median follow-up duration in the 741 patients studied during the application phase was 32.3 months (range 6-72 months). In this phase a total of 787 sentinel nodes (719 axillary and 68 intramammary chain) were obtained (range 0-5 per patient, mean 1.01), with 153 (41 with micrometastasis) positive sentinel nodes. We observed a total of three FN SLN results (0.5%). All three presented as an axillary recurrence into 24 months from operation. After a median follow-up of 32.3 months we observed only three clinical recurrences among 741 patients. Our results indicate that the sentinel node protocol can give an adequate local control.

The efficacy of 99mTc-HIG for sentinel lymph node mapping in breast cancer patients

OBJECTIVE

To evaluate the efficacy of Tc-HIG on SLN identification in patients with early-stage breast cancer.

MATERIALS AND METHODS

Seventeen women (18 tumours) with early-stage breast cancer were included. On the day of the operation, 111 MBq Tc-HIG was injected around the tumour or biopsy scar in all patients. Subsequently, dynamic lymphoscintigraphic images were taken for 30 min. After this, static images were recorded at 15-20 min intervals until the SLN was visualized. Patients were taken to the operating room 2-4 h after radiopharmaceutical injection. Before the incision, 5 ml of isosulfan blue dye solution was injected peritumourally in all subjects. Aided by blue dye and gamma probe SLN detection was done during the operation.

RESULTS

In 17/18 tumours, SLN was detected with Tc-HIG lymphoscintigraphy. The mean visualization time for axillary SLNs was 49.94+/-11.25 min and for internal mammary SLNs was 52.50+/-10.60 min. In 15 of the tumours, only one SLN was detected in the axillary region. However, in two tumours, SLNs were found in both axillary and internal mammary regions. With blue dye mapping, axillary SLNs were found in 17/18 tumours. With the application of intraoperative gamma probe, all axillary and internal mammary SLNs were detected in 18 tumours.

CONCLUSION

We conclude that Tc-HIG may be a suitable agent for SLN detection by lymphoscintigraphy and intraoperative gamma probe application in early-stage breast cancer patients.

Clinical relevance of sentinel lymph nodes in the internal mammary chain in breast cancer patients

PURPOSE

Despite the widespread use of sentinel lymph node (SLN) biopsy in breast cancer patients, some controversy exists about the correct management of extra-axillary nodes, especially those located in the internal mammary chain. The aim of this study was to evaluate the incidence of SLNs in this region, calculate the lymphoscintigraphic and surgical detection rates and evaluate the clinical impact on staging and therapeutic decisions.

METHODS

The study involved 383 consecutive women diagnosed with early breast cancer with T1 or T2 tumours. Eight patients had a bilateral tumour, which brought the total to 391 lesions. Lymphoscintigraphy was performed on the day before surgery by injection of (99m)Tc-labelled nanocolloid. The injection site was subdermal (68 patients), peritumoural (107 patients) or intratumoural (216 patients). During surgery a gamma probe was used to guide the surgeon and the SLNs were removed. SLNs were analysed by a conventional pathological study and processed for H&E examination and immunohistochemistry.

RESULTS

Lymphoscintigraphy detected at least one SLN in 369 out of the 391 procedures (94.4%). SLNs were found in the axillary chain in 367 cases and in the internal mammary chain in 55. In two of these 55 cases (3.6%), the SLN was the only one detected. There was no drainage to the internal mammary chain in any case of subdermal injection but such drainage was found in 15.9% of cases with peritumoural injection and 17.6% of those with intratumoural injection. Compared with tumours located in the outer quadrants, a higher percentage of tumours located in the inner quadrants showed drainage to the internal mammary chain (p<0.001). A total of 42 SLNs in the internal mammary chain could be removed in 32 patients without appreciable morbidity. In 20 cases both axillary and internal mammary SLNs were negative, in four both were positive, and in five axillary SLNs were positive and internal mammary SLNs were negative. More interestingly, in the remaining patient with both axillary and internal mammary SLNs, the axillary SLN was negative while malignant cells were found in the internal mammary region. In the evaluation of the clinical impact of internal mammary SLN biopsy, we found that staging was modified from pN1a to pN1c in four patients and, more importantly, from pN0 to pN0(i+) in one patient. The change in stage led to a modification of the postoperative treatment plan with respect to radiotherapy and systemic therapy.

CONCLUSION

Evaluation of the SLNs in the internal mammary chain provides more accurate staging of breast cancer patients. If internal mammary sampling is not performed, patients can be understaged. This technique can offer a better indication of those patients who will benefit from selective treatment options like radiotherapy to this region or systemic therapy.

Axillary sentinel lymph nodes in breast cancer: a single lymphatic pathway drains the entire mammary gland

AIM

To report the pattern of lymphatic mapping following intrasubdermal injections of radiocolloid and of blue dye in different sites of the breast.

METHODS

Prior to surgery 137 breast cancer patients underwent intrasubdermal injection of 30-50 MBq 99mTc-colloidal albumin over the tumour site (ISI group). Ten minutes before surgery, 2 ml patent blue was injected in the subareolar area (SAI group) in 117/137 patients, while 20 patients received intrasubdermal blue-dye in the quadrant opposite the tumour site (OQI group). The different injection routes were considered concordant when the hottest sLN was also blue.

RESULTS

In 134/137 patients radiocolloid drained to one or more axillary nodes, while blue nodes were found in 98/117 SAI patients and in 17/20 OQI patients. Multiple hot nodes were found in 63/134 cases and multiple blue nodes in 35/115. In patients in whom both tracers reached the axilla, the hottest node was also blue in 108/115 cases (93/98 SAI and 15/17 OQI patients). In the seven discordant cases, the hottest node was not blue, but in two cases the blue node was also radioactive.

CONCLUSIONS

Superficial lymphatic drainage from the breast most frequently merges to a single axillary lymph node, irrespective of the site of tracer injection. In a few cases different injection sites identify different, often closely interconnected sLNs.

Clinical axillary recurrence after sentinel node biopsy in breast cancer: a follow-up study of 220 patients

PURPOSE

The aim of this study was to evaluate the frequency of false-negative (FN) sentinel node procedures in patients with breast cancer and the subsequent clinical outcome in such patients.

METHODS

A total of 325 breast cancer patients underwent sentinel lymph node biopsy at our institution between June 1998 and May 2004. A 2-day protocol was used to localise the sentinel node with the injection of 99mTc-nanocolloid. There were two phases in the study: the learning phase (105 patients) and the application phase (220 patients). In the learning phase, a complete lymphadenectomy was always performed. In the application phase, sentinel nodes were studied intraoperatively and lymphadenectomy was performed when considered warranted by the pathological intraoperative results.

RESULTS

The median follow-up duration in the 220 patients studied during the application phase was 21.2 months (range 4-45 months). In this phase a total of 427 sentinel nodes were obtained (range 1-5 per patient, median 1.99), with 66 positive sentinel nodes in 56 patients (26%). The lymphadenectomies performed were also positive in 25% of cases (14 patients). We observed a total of two false-negative sentinel lymph node results (3.45%). One of them was found during the surgical excision of non-sentinel nodes, and the other presented as an axillary recurrence 17 months postoperatively (1.72% clinical false-negative rate). The latter patient died 1 year after the first recurrence.

CONCLUSION

After a median follow-up of 21.2 months we observed only one clinical recurrence among 220 patients. Our results indicate that adequate local control is achieved by application of the sentinel node protocol.

[Sentinel lymphonodectomy -- new surgical standard for the evaluation of the axilla:an overview. Part 1]

Complete axillary dissection is still integral component of breast cancer treatment, but significant morbidity is associated with this procedure. Sentinel lymphonodectomy can replace complete axillary dissection in selected cases and can significantly reduce morbidity. Sentinel lymphonodectomy has become a new surgical standard and should be offered to all patients with unicentric tumors of less than 3 cm in diameter. Open questions concern the localization of the market injection, the significance of detecting and extirpation of extra-axillary lymph nodes, the applicability of the method to multicentric tumors, after neoadjuvant chemotherapy, after previous breast biopsy, to DCIS and tumors of more than 3 cm in diameter. Clinical trials have to establish whether axillary dissection after finding a micrometastasis in the sentinel node is necessary or not.

Decreased identification rate of sentinel lymph node after neoadjuvant chemotherapy

We prospectively studied the feasibility of sentinel lymph node biopsy (SLNB) after neoadjuvant chemotherapy by comparing the identification rate and the false-negative rate (FNR) with the results obtained from the patients without chemotherapy. From October 2001 to March 2003, a total of 284 consecutive patients who underwent SLNB and axillary lymph node dissection (ALND) at the Center for Breast Cancer, National Cancer Center were enrolled. Of the 284 patients, 54 underwent neoadjuvant chemotherapy prior to operation. The sentinel lymph node (SLN) was mapped by radioactive colloid alone or in combination with blue dye. All SLNs were evaluated by 2 mm serial sections after hematoxylin-eosin staining. The overall SLN identification rate was 91.9% (261/284): 72.2% (39/54) of the patients after chemotherapy and 96.5% (222/230) of the patients without chemotherapy. These results suggest that preoperative chemotherapy significantly affects lymphatic mapping ( p< 0.001). Among the patients with chemotherapy, there were 3 false negatives in 39 successfully mapped tumors, yielding an FNR of 11.1% (3/27), a negative prediction value (NPV) of 80.0% (12/15), and an accuracy of 92.3% (36/39). There were 10 false negatives among 222 successfully detected patients without chemotherapy, yielding an FNR of 9.9% (10/101), an NPV of 92.4% (121/131), and an accuracy of 95.5% (212/222). These results were not statistically different when compared ( p > 0.05). Although the SLN identification rate significantly decreased after neoadjuvant chemotherapy, SLNB could accurately predict axillary status. Thus SLNB can be an alternative to ALND even after neoadjuvant chemotherapy in cases of successful identification of the SLN.

Sentinel lymph node biopsy after neoadjuvant chemotherapy

BACKGROUND

We surveyed single-center and multi-center studies pertaining to sentinel lymph node biopsy (SLNB) after neoadjuvant chemotherapy to compare the results with those of our current study to evaluate the feasibility and accuracy of SLNB after neoadjuvant chemotherapy.

METHODS

From October 2001 to July 2003, 80 patients who had neoadjuvant chemotherapy underwent curative surgery and axillary lymph node dissection (ALND) after SLNB at the Center for Breast Cancer, National Cancer Center. A MEDLINE search was performed using the keywords breast cancer, sentinel lymph node biopsy, and neoadjuvant chemotherapy.

RESULTS

Our results showed that 42 (52.6%) of 80 patients had downstaging of the primary tumor; 9 patients (11.3%) had pathologic complete response (pCR) and 33 (41.3%) had pathologic partial response (pPR). 26 patients (32.5%) showed complete axillary clearance after neoadjuvant chemotherapy. Among them, 5 patients (6.3%) revealed pCR of both the primary tumor and axillary metastasis. SLNB was successful in 61 of 80 patients (76.3%) and there were 3 false negatives, yielding a false negative rate (FNR) of 7.3% (3/41), a negation prediction value (NPV) of 87.0%(20/23), and an accuracy of 95.1% (58/61). Thirteen out of 16 studies retrieved by to MEDLINE pertaining SLNB after neoadjuvant chemotherapy concluded its feasibility and accuracy with a identification rate of 82%-100% and a FNR of 17-100%.

CONCLUSION

Most studies, including ours, concluded that SLNB after neoadjuvant chemotherapy is accurate and could be an alternative to ALND.

Population-based sentinel lymph node biopsy in early invasive breast cancer

INTRODUCTION

Sentinel lymph node biopsy (SLNB) has been proposed as a reliable method for staging of early invasive breast cancer (EIBC). In the present study we analyse the impact of this procedure when systematically applied to all unselected women of a community-based Breast Cancer Unit (BCU).

METHODS

All consecutive women with unifocal cT1-2 (<or=3 cm) cN0 EIBC diagnosed at our BCU were considered for radiocolloid sentinel node localisation and biopsy.

RESULTS

Only 387 of all consecutive 542 patients met eligibility criteria for SLNB. Reasons for ineligibility included tumour size, palpable axillary nodes, plurifocality and/or multicentricity, and refusal to undergo the procedure. Successful SLNB was performed in 362 patients (94% of those eligible), but in 108 of these axillary dissection (AD) had to be performed anyway, mainly because of SLN-positivity. Therefore, SLNB ultimately allowed sparing axillary dissection in 256 patients out of the entire population of women with EIBC.

CONCLUSIONS

Radiocolloid-guided SLNB, when appropriately applied in the context of a population-based service, can help in sparing unnecessary AD, with its related costs and morbidity, in approximately half of all women presenting with EIBC. In absolute terms, in the EU this could result in approximately 100,000 unnecessary AD avoided each year.

[Sentinel lymph node biopsy in breast cancer]

Surgical treatment of breast cancer has changed dramatically during the last few decades with the aim of reducing surgical radicality in the breast and also in the axilla. In this context sentinel node biopsy is a reliable technique to determine axillary node status of breast cancer patients and reduce morbidity associated with standard axillary lymph node dissection. Although SNB is performed with increasing frequency, an incorrect indication and lack of experience with the surgical procedure can minimize the sensitivity and specificity of this method. In consequence, this could lead to wrong tumor staging and inappropriate adjuvant therapy. Therefore, we describe the basic requirements, indications, and pitfalls of this technique. Since many issues are controversial such as the prognostic value of micrometastases and extramammary nodes as well as the use of SNB after primary chemotherapy and in ductal carcinoma in situ, further clinical studies are necessary.