Factors of importance for scintigraphic non-visualisation of sentinel nodes in breast cancer

Nonvisualized sentinel node on preoperative lymphoscintigraphy in primary cutaneous melanoma: an 11-year retrospective survey

BACKGROUND

Sentinel lymph node (SLN) biopsy in cutaneous melanoma patients evaluates the regional draining basin for occult micrometastatic disease. Occasionally, nonidentification of SLN impairs the acquisition of this important prognostic factor.

OBJECTIVES

To investigate the outcomes of melanoma patients with negative lymphoscintigraphic findings and patients who underwent SLN biopsy from 2004 to 2015 ( n  = 1200) were retrospectively reviewed for tumor characteristics and clinical outcomes.

METHODS

Patients with nonvisualized lymph nodes (NV group) who underwent only preoperative lymphoscintigraphy were separated and compared with a cohort drawn from all melanoma patients who completed the surgical procedure within the same period (V group).

RESULTS

A negative lymphoscintigraphic scan was observed in 38 cases (3.2% of all patients). The NV group showed a significantly older age (median 66.0 vs. 48.3 years; P  < 0.0001). Head and neck melanomas were more frequent in the NV group compared to the control group (25.1 vs. 7.8%; P  = 0.009). Tumor characteristics such as ulceration and Breslow thickness do not influence the lymphoscintigraphy result. No differences were found in overall survival (OS) and disease-free survival (DFS) between the groups.

CONCLUSIONS

The nonvisualization of regional lymph nodes by lymphoscintigraphy is more frequent in older patients with head and neck melanomas. From the clinical point of view, no specific recommendation emerged for patients' management because the nonvisualization of the SLN did not show a significant influence on DFS and OS rates. However, lack of knowledge of lymph node status suggests performing a tighter follow-up eventually by ultrasound evaluation of all potential lymph node drainage basins.

Anatomical breast imaging-derived parameters do not provide incremental information in prediction of nonvisualization of sentinel lymph nodes on lymphoscintigraphy

OBJECTIVE

Accurate sentinel lymph node (SLN) staging is essential for both prognosis and treatment in patients with breast cancer. However, the preoperative lymphoscintigraphy may fail to visualize the SLN. The aim of this retrospective study was to investigate whether parameters derived from anatomical breast imaging can predict SLN nonvisualization on lymphoscintigraphy.

METHODS

For this retrospective study, all data of mammography, breast MRI, and lymphoscintigraphy of SLN procedures from January 2016 to April 2021 were collected and reviewed from the Amsterdam UMC database.

RESULTS

A total of 758 breast cancer patients were included in this study. SLN nonvisualization on planar lymphoscintigraphy at 2-h postinjection (pi) was 29.7% and was reduced after a second injection to 7.5% at late lymphoscintigraphy 4-h pi. Multivariable analysis showed that age ≥ 70 years ( P = 0.019; OR, 1.82; 95% CI, 1.10-3.01), BMI ≥ 30 kg/m 2 ( P = 0.031; OR, 1.59; 95% CI, 1.04-2.43), and nonpalpable tumors ( P = 0.034; OR, 1.54; 95% CI, 1.03-2.04) were independent predictors of SLN nonvisualization. Differences in tumor size, Breast Imaging-Reporting and Data System classification, or breast density were not significantly associated with SLN nonvisualization.

CONCLUSION

This study shows that, by using a multivariable analysis, risk factors for SLN nonvisualization in breast cancer patients during preoperative lymphoscintigraphy at 2-h pi are age ≥ 70 years, BMI ≥ 30 kg/m 2 , and nonpalpable tumors. Parameters derived from mammography or breast MRI, however, are not useful to predict SLN nonvisualization on lymphoscintigraphy.

Does failed mapping predict sentinel lymph node metastasis in cN0 breast cancer?

Aims: The clinical significance of nonvisualized sentinel lymph nodes (non-vSLNs) is unknown. The authors sought to determine the incidence of non-vSLNs on lymphoscintigraphy, the identification rate during surgery, factors associated with non-vSLNs and related axillary management. Patients & methods: A total of 30,508 consecutive SLN procedures performed at a single institution from 2000 to 2017 were retrospectively studied. Associations between clinicopathological factors and the identification of SLNs during surgery were assessed. Results: Non-vSLN occurred in 525 of the procedures (1.7%). In 73.3%, at least one SLN was identified intraoperatively. Nodal involvement was only significantly associated with SLN nonidentification (p < 0.001). Conclusion: Patients with non-vSLN had an increased risk for SLN metastasis. The detection rate during surgery was consistent, reducing the amount of unnecessary axillary dissection.

Risk factors for nonvisualization of the sentinel lymph node on lymphoscintigraphy in breast cancer patients

Background

Accurate sentinel lymph node (SLN) staging is essential for both prognosis and treatment in patients with breast cancer. However, the preoperative lymphoscintigraphy may fail to visualize the SLN in some patients. The purpose of this retrospective study was to identify risk factors associated with SLN nonvisualization on lymphoscintigraphy. For this single-center retrospective study, all data of lymphoscintigraphy of SLN procedures from March 2011 to April 2021 were collected and reviewed from the Amsterdam UMC database.

Results

A total of 1886 SLN procedures were included in this study. The SLN nonvisualization rate was 25.1% on lymphoscintigraphy at 4 h post-injection. The SLN nonvisualization rate decreased to 9.4% after reinjection. Multivariable analysis showed that age ≥ 70 years (P < 0.001; OR: 2.27; 95% CI: 1.46–3.53), BMI ≥ 30 kg/m² (P = 0.031; OR: 1.48; 95% CI: 1.04–2.12) and nonpalpable tumors (P = 0.004; OR: 1.54; 95% CI: 1.15–2.07) were independent predictors of SLN nonvisualization. Tumor location, brand of radiopharmaceutical, injected dose and volume, experience of preparer and administrator were not associated with SLN nonvisualization. None of the patient, tumor or tracer characteristics were associated with SLN nonvisualization after radiotracer reinjection.

Conclusions

This study shows that risk factors for SLN nonvisualization in breast cancer patients during preoperative lymphoscintigraphy are age ≥ 70 years, BMI ≥ 30 kg/m² and nonpalpable tumors. Our results support the notion that SLN lymphoscintigraphy is a very robust technique that does not depend on the experience of the preparer or administrator of the radiotracer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13550-021-00793-8.

Prognostic Role of Non-Identification of Sentinel Lymph Node in Cutaneous Melanoma Patients: An Observational Retrospective Study

Simple Summary

Sentinel lymph node status is the most important prognostic factor for patients with cutaneous melanoma, but occasionally it is not possible to identify the sentinel lymph node. Little is known in cutaneous melanoma literature about the phenomenon of non-identification of sentinel lymph node and its prognostic implications. In this study we observed that not identifying the sentinel lymph node involves a worse nodal disease-free survival, but not a worse melanoma-specific survival than a negative sentinel lymph node. Potentially, patients with non-identified SLN should receive a follow-up schedule like that of patients with positive SLN.

Abstract

Background: Sentinel lymph node (SLN) status is recognized as the most important prognostic factor for patients with cutaneous melanoma. However, sometimes it is not possible to identify SLN. The phenomenon of non-identification of SLN and its prognostic role have not been thoroughly evaluated in melanoma literature. The objective of this study was to identify which patient or tumor variables may be associated to non-identification of SLN and to evaluate the prognostic role of non-identification of SLN. Methods: Observational retrospective study of 834 cutaneous melanoma patients who underwent SLN biopsy at Instituto Valenciano de Oncología. Results: Forty-two patients (5%) presented non-identification of SLN. Patients with age at diagnosis of ≥ 64 years, obesity (BMI ≥ 30), and head and neck localization were at higher risk of non-identification of SLN. Non-identified SLN patients had worse nodal disease-free survival with respect to negative SLN patients, but not worse melanoma-specific survival. Conclusions: Our findings suggest a need to follow-up patients with non-identified SLN in the same way as patients with positive SLN.

Predictive risk factors for sentinel lymph node nonvisualization on planar lymphoscintigraphy using an intratumoral injection in patients with primary breast cancer

OBJECTIVES

Lymphoscintigraphy is considered a useful tool to optimize sentinel lymph node (SLN) identification. Nonvisualization of the SLN is associated with a lower SLN identification rate. The aim of this study was to identify preoperative factors associated with SLN nonvisualization on lymphoscintigraphy.

PATIENTS AND METHODS

A total of 2050 consecutive SLN procedures were evaluated from clinically node-negative breast cancer patients. Planar lymphoscintigraphy was performed at 3 h after an intratumoral injection of technetium-99m-nanocolloid. This technique was used for extra-axillary SLN identification. Patient, tumor, and treatment characteristics were analyzed for association with SLN nonvisualization. Factors with a P-value less than 0.1 in univariate analysis were included in a multivariate logistic regression model.

RESULTS

The SLN visualization rate was 86.7%. In multivariate logistic regression, age of at least 70 years [odds ratio (OR): 3.24; 95% confidence interval (CI): 2.14-4.91)], BMI of at least 30 (OR: 1.93; 95% CI: 1.39-2.69), T3/T4-tumors (OR: 2.70; 95% CI: 1.37-5.32), medially/centrally located tumors (OR: 1.52; 95% CI: 1.17-1.99), previous mantle field radiation (OR: 4.04; 95% CI: 1.74-9.35), nonpalpable tumors (OR: 1.88; 95% CI: 1.36-2.60), and presence of iodine seeds (OR: 1.35; 95% CI: 1.02-1.78) were associated significantly with nonvisualization on lymphoscintigraphy. Nonvisualization was the strongest independent predictor of unsuccessful intraoperative SLN identification (P<0.001). Overall, the SLN identification rate was 97.7% because of the use of additional imaging and blue dye.

CONCLUSION

This study reports new tumor and treatment-related risk factors for nonvisualization on lymphoscintigraphy by using an intratumoral injection in primary breast cancer. We recommend a periareolar subcutaneous injection to improve SLN visualization in patients with limited prognostic and therapeutic relevance of internal mammary chain SLN identification.

Biological Subtypes of Breast Cancer and Sentinel Lymph Node Biopsy

Objective

Breast cancer subtypes are used as prognostic and predictive factors considering the genomic profile of the disease. This study is designed to investigate the Sentinel Lymph Node (SLN) detection rate in breast cancer for different biological characteristics.

Material and Methods

Patients on whom we performed the methylene blue method alone were named as Group I, radiocolloid substance method alone as Group II and both methylene blue and radiocolloid method as Group III. The results of biological tumor characteristics and characteristics of the patients on different SLN biopsy techniques were investigated.

Results

The overall SLN detecting success rate was 83.3%. When considered for each group, success rate was 80% for group I, 84.9% for group II and 90.6% for group III. While a success rate of 94.6% was achieved with radiocolloid only in the patients in Luminal A and B subgroup, 90% success rate was achieved in Her2 (+) and triple negative (TN) patients with combined method.

Conclusion

While successful results could be achieved by using radiocolloid substances alone in patients with Luminal A and B subtypes, combined methods should be used in HER2 (+) and TN patients.

Sentinel lymph node identification using superparamagnetic iron oxide particles versus radioisotope: The French Sentimag feasibility trial

BACKGROUND AND OBJECTIVES

The French Sentimag feasibility trial evaluated a new method for the localization of breast cancer sentinel lymph node (SLN) using Sienna+®, superparamagnetic iron oxide particles, and Sentimag® detection in comparison to the standard technique (isotopes ± blue dye).

METHODS

We conducted a prospective multicentric paired comparison trial on 115 patients. SLN localization was performed using both the magnetic technique and the standard method. Detection rate and concordance between magnetic and standard tracers were calculated. Post-operative complications were assessed after 30 days.

RESULTS

Results are based on 108 patients. SLN identification rate was 98.1% [93.5-99.8] for both methods, 97.2% [92.1-99.4] for Sienna+® and 95.4% [89.5-98.5] for standard technique. A mean of 2.1 SLNs per patient was removed. The concordance rate was 99.0% [94.7-100.0%] per patient and 97.4% [94.1-99.2] per node. Forty-six patients (43.4%) had nodal involvement. Among involved SLNs, concordance rate was 97.7% [88.0-99.9] per patient and 98.1% [90.1-100.0] per node.

CONCLUSIONS

This new magnetic tracer is a feasible method and a promising alternative to the isotope. It could offer benefits for ambulatory surgery or sites without nuclear medicine departments. J. Surg. Oncol. 2016;113:501-507. © 2016 Wiley Periodicals, Inc.

Sentinel Lymph Node Detection in Contralateral Axilla at Initial Presentation of a Breast Cancer Patient: Case Report

The main basin for breast lymphatic drainage is ipsilateral axilla. However, extra-axillary drainage may be seen in some patients. The most common extra-axillary site is internal mammary chain, while contralateral axillary drainage is an extremely rare situation in previously untreated patients. We describe a case of untreated right breast retroareolar carcinoma with contralateral axillary drainage detected on preoperative lymphoscintigraphy. Contralateral axillary dissection was performed based on the result of frozen section examination of the sentinel lymph node (SLN) which turned out to burden micrometastasis. Postoperative histopathological examination revealed invasive ductal carcinoma metastasis in 17 out of 22 lymph nodes from the ipsilateral axillary dissection, whereas 14 lymph nodes from contralateral axillary dissection other than the SLN were nonmetastatic. In our opinion, determination of contralateral axillary metastasis in primary staging process had a major contribution to the management of the patient.

[Sentinel node in melanoma and breast cancer. Current considerations]

The main objectives of sentinel node (SN) biopsy is to avoid unnecessary lymphadenectomies and to identify the 20-25% of patients with occult regional metastatic involvement. This technique reduces the associated morbidity from lymphadenectomy and increases the occult lymphatic metastases identification rate by offering the pathologist the or those lymph nodes with the highest probability of containing metastatic cells. Pre-surgical lymphoscintigraphy is considered a "road map" to guide the surgeon towards the sentinel nodes and to localize unpredictable lymphatic drainage patterns. The SPECT/CT advantages include a better SN detection rate than planar images, the ability to detect SNs in difficult to interpret studies, better SN depiction, especially in sites closer to the injection site and better anatomic localization. These advantages may result in a change in the patient's clinical management both in melanoma and breast cancer. The correct SN evaluation by pathology implies a tumoral load stratification and further prognostic implication. The use of intraoperative imaging devices allows the surgeon a better surgical approach and precise SN localization. Several studies reports the added value of such devices for more sentinel nodes excision and a complete monitoring of the whole procedure. New techniques, by using fluorescent or hybrid tracers, are currently being developed.

The Central-European SentiMag study: sentinel lymph node biopsy with superparamagnetic iron oxide (SPIO) vs. radioisotope

Sentinel lymph node biopsy (SLNB) is the standard surgical procedure for the axilla in early node-negative breast cancer. To date, the "gold standard" to localize the sentinel lymph node (SLN) is the radiotracer (99m)Tc with or without blue dye. The aim of this study was to evaluate potential equivalency of the new SentiMag(®) technique in comparison to the "gold standard". Within this prospective, multicentric and multinational non-inferiority study including 150 patients (99m)Tc was compared with the magnetic technique, using superparamagnetic iron oxide particles (SPIOs, Sienna+(®)) for localization of SLNs. The results showed a detection rate per patient of 97.3% (146/150) for (99m)Tc vs. 98.0% (147/150) for Sienna+(®) with a similar average number of removed SLNs per patient and a higher per patient malignancy detection rate for the SPIO tracer. We obtained convincing results that magnetic SLNB can be performed easily, safely and equivalently well in comparison to the radiotracer method.

Tumor-infiltrating lymphocyte response in cutaneous melanoma in the elderly predicts clinical outcomes

Tumor-infiltrating lymphocytes (TILs) and regression are manifestations of the host immune response to tumor, but their influence on outcome remains undefined. There is a paucity of data on the elderly who represent a growing proportion of melanoma patients. The aim of this study was to evaluate the influence of TILs and regression as an indirect measure of immunity on outcome in elderly patients with melanoma. From a prospective database, we identified 250 consecutive cutaneous melanoma patients aged at least 65 years at the time of diagnosis. Data were verified by record review. Within the primary melanoma, a brisk TIL response was present in 66 (31%), nonbrisk TILs in 36 (17%), and absent in 111 (52%). The presence of a brisk infiltrate conferred a three-fold increased risk of sentinel lymph node (SLN) metastasis (P=0.02). Despite this, nonbrisk or absent TILs were associated with a five-fold increased risk of recurrence (P=0.0001). In multivariate analysis, nonbrisk or absent TILs were independently associated with recurrence (P<0.0001), diminished 5-year disease-free survival (76 vs. 91%, P=0.0006), and 5-year melanoma-specific survival (82 vs. 95%, P=0.0008). Regression was not an independent predictor of SLN metastasis, disease-free survival, or melanoma-specific survival. Our study demonstrates that an active antitumor immune response exists in elderly melanoma patients that, paradoxically, predicts both SLN metastasis and improved melanoma-specific outcomes. Further investigation to characterize this lymphocytic infiltrate and to confirm its clinical significance as a predictor of nodal status, patient outcome, and response to immunotherapy in elderly melanoma patients appears warranted.

Prevalence and risk factors of intraoperative identification failure of sentinel lymph nodes in patients affected by breast cancer

INTRODUCTION

Sentinel lymph node biopsy (SLNB) has progressively replaced complete axillary lymph node dissection in the evaluation of breast cancer patients with clinically node-negative disease. Our study investigates the rate of and risk factors involved in sentinel node identification failure.

MATERIALS AND METHODS

We collected data on SLNBs performed during 2002-2010, focusing on tumor, patient, and breast characteristics, radioactivity parameters, and operators' experience. Data were analyzed by R (v2.14.2), considering significance at P values lower than 0.05.

RESULTS

Among 1050 women who underwent an SLNB, the rate of identification failure was 2% (23/1050), which, on bivariate analysis, was seen to be significantly influenced (P<0.05) by the preoperative and intraoperative low radiotracer uptake (axilla/lesion radiotracer uptake ratio<1%), low level of experience of the specialist in nuclear medicine, luminal A subtype, and radiotracer uptake localization in internal mammary lymph nodes. On multivariate analysis, significant risk factors for sentinel node identification failure were found to be: axilla/lesion radiotracer uptake ratio less than 1%, radiotracer uptake localization in internal mammary lymph nodes, and luminal A subtype. Considering only the preoperative variables in our multivariate analysis, axilla/lesion radiotracer uptake ratio less than 1%, negative lymph node scintiscan, and radiotracer uptake localization in internal mammary lymph nodes had an area under the curve (receiver operating characteristic curve) of 96% (95% confidence interval 92-100%). Further, we built a nomogram based on these simple parameters for counseling the patient about the probability of not finding the sentinel lymph node during the surgical procedure.

CONCLUSION

The relatively low prevalence of SLNB failure (2%) is indicative of the accuracy of the procedure when performed by experienced surgeons. The sentinel node identification failure in our population seemed to be related to biological tumor factors (luminal A subtype) and probably to physiological or pathological variations in the lymphatic drainage (axilla/lesion radiotracer uptake ratio<1% and radiotracer uptake localization in internal mammary lymph nodes).

Reproducibility of lymphoscintigraphy before and after excisional biopsy of primary breast lesions: a study using superficial peri-areolar injection of the radiotracer

OBJECTIVE

A major controversial issue in the sentinel node biopsy of the breast is the applicability of sentinel node mapping in patients with the history of previous excisional biopsy of the breast lesions. In the current study, we evaluated the reproducibility of lymphoscintigraphy before and after excisional biopsy of the primary breast lesions using superficial peri-areolar injection of the radiotracer.

MATERIAL AND METHODS

Eighteen patients scheduled for excisional biopsy of breast lesions were included into the study. The patients received intra-dermal injection of the radiotracer in the peri-areolar area of the index quadrant 1 to 2h before surgery. Imaging was performed the day after surgery. Immediately after completion of the first imaging, the patients received another injection of the radiotracer with the same technique, dose, and location. Other sets of lymphoscintigraphy imaging were taken immediately and 4h post second injection. The two sets of lymphoscintigraphy images were compared.

RESULTS

In 2 patients, sentinel node could not be identified in either set of images. In the remaining 16 patients, one sentinel node was detected in both lymphoscintigraphy image sets. The sentinel nodes of the second image sets were all in the same location of the first sets with at least 5 times higher count.

CONCLUSIONS

Excisional biopsy of the primary breast lesions does not seem to change the superficial lymphatic drainage pattern from the areola of the breast and sentinel node mapping can be performed after this procedure using superficial periareolar technique.

Clinical and histopathological factors affecting failed sentinel node localization in axillary staging for breast cancer

BACKGROUND

Sentinel lymph node biopsy (SLNB) has become the standard of care in axillary staging of clinically node-negative breast cancer patients.

AIMS

To analyze reasons for failure of SLN localization by means of a multivariate analysis of clinical and histopathological factors.

METHODS

We performed a review of 164 consecutive breast cancer patients who underwent SLNB. A superficial injection technique was used.

RESULTS

9/164 patients failed to show nodes. In 7/9 patients no evidence of radioactivity or blue dye was observed. Age and nodal status were the only statistically significant factors (p < 0.05). For every unit increase in age there was a 9% reduced chance of failed SLN localization. Patients with negative nodal status have 90% reduced risk of failed sentinel node localization than patients with macro or extra capsular nodal invasion.

DISCUSSION

The results suggest that altered lymphatic dynamics secondary to tumour burden may play a role in failed sentinel node localization. We showed that in all failed localizations the radiocolloid persisted around the injection site, showing limited local diffusion only. While clinical and histopathological data may provide some clues as to why sentinel node localization fails, we further hypothesize that integrity of peri-areolar lymphatics is important for successful localization.

Factors influencing the time of sentinel node visualization in breast cancer patients using intradermal injection of the radiotracer

BACKGROUND

The objective of our study was to determine the important factors that have influence on the time of sentinel node visualization using intradermal injection of (99m)Tc-antimony sulfide colloid.

METHODS

Two hundred fifty consecutive patients with the diagnosis of early-stage breast cancer were evaluated. Anterior and lateral views were acquired in various intervals after intradermal injection of the tracer until 180 minutes or visualization of the sentinel node. The effect of several variables on the time of sentinel node visualization was evaluated by univariate and multivariate analyses.

RESULTS

The time of sentinel node visualization was significantly correlated with age, body mass index (BMI), and interval between biopsy and sentinel node mapping. Standardized beta values for these variables were .1, .3, -.55 respectively.

CONCLUSIONS

Older age and higher BMI can result in slow sentinel node visualization. Longer interval between biopsy and sentinel node mapping can be associated with rapid sentinel node detection.

Sentinel lymph node biopsy and survival in elderly patients with cutaneous melanoma

BACKGROUND

Sentinel lymph node biopsy (SNB) is a widely adopted staging procedure in patients with cutaneous melanoma. The benefits of SNB have not been evaluated thoroughly in older age groups.

METHODS

This was a two-centre retrospective observational study of patients with melanoma aged at least 70 years undergoing SNB.

RESULTS

A total of 423 patients were included. SNB was successful in 405 patients (95·7 per cent), of whom 88 (21·7 per cent) had sentinel node metastasis. During a median follow-up of 2·5 years, recurrence developed in 80 patients (18·9 per cent). Nodal recurrence developed in eight sentinel node-negative patients, giving a false-negative rate of 8·3 per cent, a sensitivity of 91·7 per cent and an overall diagnostic accuracy of 98·0 per cent. A total of 46 patients (10·9 per cent) died from melanoma and 42 (9·9 per cent) from other causes. At 5 years, the relapse-free survival rate was 80·0 per cent in sentinel node-negative patients and 39 per cent in node-positive patients; cancer-specific survival rates were 88·6 per cent and 46 per cent respectively (P < 0·001). In multivariable analysis, sentinel node metastasis (P < 0·001), a Breslow thickness of at least 2·0 mm (P = 0·007) and presence of ulceration (P = 0·012) were independent prognostic factors for cancer-specific survival.

CONCLUSION

SNB is a feasible and accurate technique for detecting nodal metastases in older patients with melanoma. Sentinel node status is the most important predictor of cancer-specific outcome in the elderly.

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

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

Axillary sentinel node identification in breast cancer patients: degree of radioactivity present at biopsy is critical

BACKGROUND

The radioactivity present in the patient (Act(rem) ) at sentinel node (SN) biopsy will depend on injected activity amount as well as on the time interval from tracer injection to biopsy, which both show great variations in the literature. The purpose of this study was to analyse the influence of varying Act(rem) levels on the outcome of axillary SN biopsy in patients with breast cancer (BC).

MATERIAL AND METHODS

Eight hundred and fifty-eight patients with BC were consecutively referred to SN biopsy, 21% for a same-day and 79% of the patients for a 2-day procedure. Four hundred and nineteen patients underwent scintigraphy and 439 did not. For same-day procedures, 50 MBq (99m) Tc-nanocolloid (Nanocoll(®) ) was injected, and for 2-day procedures 110 MBq. For the analysis of SN biopsy outcome, the patients were divided into three Act(rem) groups: <10 (56% of the patients), 10-20 (23%), and >20 MBq (21%). During surgery, SNs were located using a hand-held gamma probe supported by image information when available and blue dye injection. Pathology included haematoxylin-eosin staining followed by immunohistochemistry.

RESULTS

The number of SNs removed (mean value 1·87 versus 2·14, P = 0·0003) and the probability of finding a malignant SN (P = 0·034) were lower in the <10 MBq group of patients compared with higher Act(rem) >20 MBq. Of the 25 patients with SN non-detection, 20 patients had an Act(rem) <10 MBq. Imaging had no significant influence on the number of patients with a malignant SN (P = 0·48).

CONCLUSION

Act(rem) above 10 MBq for nanocolloid tracer appears important for appropriate identification of SNs in patients with BC.

Current controversies in the management of patients with early-stage vulvar cancer

PURPOSE OF REVIEW

The purpose of this review is to outline current controversies in management of early-stage vulvar cancer. The main focus will be on the procedures for assessing the sentinel node and the treatment of those with evidence of metastatic involvement.

RECENT FINDINGS

Assessment of the sentinel node has recently been introduced into the standard treatment of early-stage squamous cell vulvar cancer. The combination of a radioactive tracer and blue dye is the most accurate technique for sentinel node detection. Preoperative imaging is recommended to rule out gross nodal involvement and ultrasound with fine needle aspiration cytology by an experienced radiologist appears to have the highest sensitivity/specificity for detecting metastases, although large comparative studies are not available. All patients with sentinel node metastases require additional treatment to the groin, independent of the size of metastasis in the sentinel node and currently this involves inguinofemoral lymphadenectomy. Further research is ongoing to investigate the role of radiotherapy instead of lymphadenectomy. The little experience there is of sentinel node biopsy in vulvar melanoma suggests that the procedure is feasible and inclusion criteria should follow those of cutaneous melanoma.

SUMMARY

Sentinel node biopsy is safe in treatment of early-stage vulvar cancer. Ongoing studies are investigating the optimal additional treatment for patients with a positive sentinel node in terms of efficacy and morbidity.

Added value of intraoperative real-time imaging in searches for difficult-to-locate sentinel nodes

Localization of sentinel lymph nodes can be challenging if they are in difficult anatomic locations or near high radiotracer activity. The purpose of this study was to assess the value of intraoperative real-time imaging using a portable gamma-camera in conjunction with a conventional gamma-counting probe when it is difficult to localize the sentinel node.

METHODS

After (99m)Tc-nanocolloid injection, patients with various malignancies underwent presurgical lymphoscintigraphy followed by surgery (usually the next day). We evaluated 20 patients who required sentinel lymph node biopsy and in whom the location or other characteristics of the sentinel node would make intraoperative retrieval difficult. During surgery, the sentinel node was localized using a portable gamma-camera together with a hand-held gamma-probe. A (153)Gd pointer or (125)I seed was used to better depict the sentinel node location in real time.

RESULTS

Using only a conventional hand-held gamma-probe, surgeons were able to definitively localize the sentinel node in 15 of 20 patients. Intraoperatively, the portable gamma-camera showed uptake by the definite sentinel node in 19 of 20 patients and helped to precisely localize the node with the hand-held gamma-probe in 4 patients. In 1 of these patients, the sentinel node was metastatic.

CONCLUSION

The combination of a standard hand-held gamma-probe and real-time imaging provided by a portable gamma-camera offers a high intraoperative detection rate in patients with difficult sentinel node localization as assessed by presurgical lymphoscintigraphy.

Sentinel node identification rate and nodal involvement in the EORTC 10981-22023 AMAROS trial

Background

The randomized EORTC 10981-22023 AMAROS trial investigates whether breast cancer patients with a tumor-positive sentinel node biopsy (SNB) are best treated with an axillary lymph node dissection (ALND) or axillary radiotherapy (ART). The aim of the current substudy was to evaluate the identification rate and the nodal involvement.

Methods

The first 2,000 patients participating in the AMAROS trial were evaluated. Associations between the identification rate and technical, patient-, and tumor-related factors were evaluated. The outcome of the SNB procedure and potential further nodal involvement was assessed.

Results

In 65 patients, the sentinel node could not be identified. As a result, the sentinel node identification rate was 97% (1,888 of 1,953). Variables affecting the success rate were age, pathological tumor size, histology, year of accrual, and method of detection. The SNB results of 65% of the patients (n = 1,220) were negative and the patients underwent no further axillary treatment. The SNB results were positive in 34% of the patients (n = 647), including macrometastases (n = 409, 63%), micrometastases (n = 161, 25%), and isolated tumor cells (n = 77, 12%). Further nodal involvement in patients with macrometastases, micrometastases, and isolated tumor cells undergoing an ALND was 41, 18, and 18%, respectively.

Conclusions

With a 97% detection rate in this prospective international multicenter study, the SNB procedure is highly effective, especially when the combined method is used. Further nodal involvement in patients with micrometastases and isolated tumor cells in the sentinel node was similar—both were 18%.

Age-related lymphatic dysfunction in melanoma patients

BACKGROUND

Age-related outcomes have become increasingly common in evaluating patients with melanoma. For instance, as age increases, sentinel node (SN) nonidentification increases and SN positivity decreases. Furthermore, advanced age is a risk factor for in-transit disease. We hypothesized that increasing age is accompanied by alterations in lymphatic function, possibly explaining these findings.

METHODS

Our center's melanoma database was queried to identify patients who underwent successful sentinel node biopsy after lymphoscintigraphy. Records of those treated between 2000 and 2005 were reviewed for age, sex, drainage basin, intraoperative radioactivity, and SN pathology.

RESULTS

The 858 patients had a mean age of 55 years; 59% were men. Mean radioactivity in the hottest SN was 5232 counts per second; 179 patients (21%) had SN metastases. SN count rates were significantly and inversely related to age (P < .001 by Pearson correlation, analysis of variance, and chi(2) test). Mean counts per second were 6105, 5883, and 2720 for axillary, inguinal, and cervical basins, respectively (P < .01), and count rates in these basins were consistently lower with increasing age (neck and axilla, P < .001; groin, P = .060; Pearson correlation). Multivariate analysis confirmed an independent inverse association between age and count rates (P < .001), overall and within each primary tumor site.

CONCLUSIONS

Lymphatic function, as assessed by radiocolloid transit to and uptake within the SN, declines with age. Altered lymphatic function in older patients may modify metastatic patterns; knowledge of this may help clarify findings of reduced nodal positivity and increased in-transit disease in this population.

One-day or two-day procedure for sentinel node biopsy in melanoma?

PURPOSE

We compared the outcome of a 1-day and a 2-day sentinel node (SN) biopsy procedure, evaluated in terms of lymphoscintigraphic, surgical and pathological findings.

METHODS

We studied 476 patients with melanoma from two melanoma centres using static scintigraphy and blue dye. A proportional odds model was used for statistical analysis.

RESULTS

The number of SNs visualized at scintigraphy increased significantly with time from injection to scintigraphy and activity left in the patient at scintigraphy, and depended on the melanoma location. The number of SNs removed at surgery increased with the number of SNs visualized at scintigraphy and time from injection to surgery. The frequency of nodal metastasis increased with increasing thickness and Clark level of the melanoma, and was highest for two SNs visualized at scintigraphy.

CONCLUSION

This study showed that early vs. late imaging and surgery do make a difference on the outcome of the SN procedure and confirmed the importance of the scintigraphic visualization of all true SNs.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Use of contrast-enhanced ultrasound imaging to detect the first draining lymph node (FDLN) in a swine model: correlation of imaging findings with the distance from the injection site to the FDLN

OBJECTIVE

The purpose of this study was to investigate the use of contrast-enhanced ultrasound imaging (CEUS) to detect the first draining lymph node (FDLN) in a swine model and to determine whether the distance from the contrast agent injection site to the FDLN has any affect on the ability to detect contrast-enhanced FDLNs.

METHODS

Thirteen swine (25-32 kg) were anesthetized during examinations and euthanized afterward. In every swine, 1 mL of a sulfur hexafluoride microbubble ultrasound contrast agent was bilaterally injected subcutaneously below a mammilla. The examined distances varied from 6 to 36 cm. The contrast-enhanced lymphatic channels were visualized with low-mechanical index CEUS and mapped from the injection site to the FDLN. After CEUS was performed, blue dye was injected in the same locations as the contrast agent, and dye-guided surgery was used to localize the FDLNs. To ensure the lymph node detected with the blue dye technique was the same found with CEUS, it was scanned again to confirm contrast enhancement.

RESULTS

After 26 injections, 22 inguinal FDLNs were detected with CEUS and the blue dye technique. After 4 injections in 2 swine, contrast-filled lymphatic channels were identified with a course running toward the neck. In all cases but 1, the FDLNs received the contrast agent within 5 minutes.

CONCLUSIONS

In this swine model, it was possible to use CEUS to locate the FDLNs. In these preliminary experiments, the distances from the contrast agent injection site to the FDLN did not affect the ability to detect the contrast-enhanced FDLNs.

Current technical overviews of sentinel lymph node biopsy for breast cancer

Sentinel lymph node biopsy (SLNB) is based on the hypothesis that the sentinel lymph node (SLN) reflects the lymph-node status and a negative SLN might allow complete axillary lymph node dissection (ALND) to be avoided. Although the survival outcome is still unknown, this technique has already become a standard of care for breast cancer patients. However, it is still important to discuss current techniques and some controversies. This article reviews these issues for a variety of SLNB techniques.

Advantages of upright position imaging with medium-energy collimator for sentinel node lymphoscintigraphy in breast cancer patients

OBJECTIVE

To evaluate the advantage of upright position imaging with a medium-energy collimator for the detection of sentinel lymph node (SLN).

METHODS

Thirty-four patients with operable breast cancer underwent sentinel node lymphoscintigraphy with 99mTc-tin colloid. Images were obtained in 5 different positions and paired images from the same patient were compared using side-by-side interpretation. Images were compared in 3 groups: group 1 (anterior view); supine (SAV) vs. upright (UAV), group 2 (oblique view); supine (SOV) vs. upright (UOV), and group 3 (oblique view); modified supine (MOV) vs. UOV. Image quality was evaluated using a 3-grade scale of clear, faint, and equivocal depiction, and correlated to 3 parameters: distance from injection site to lymph node (hot node), counts in hot node, and image contrast. Parameters in group 1 were compared by classifying the primary tumor site into 4 subregions.

RESULTS

Image quality in all 3 groups was more enhanced on the image obtained in the upright position than that in the supine position. Obtaining images in an upright position increased the mean distances by 1.5-3.2 cm, and mean contrasts were significantly increased by 0.13-0.31 (p < 0.05). It was shown that image quality was more greatly affected by image contrast than by counts in the hot node. Image contrast of 0.5 seemed an appropriate threshold level for detection of the hot node. On comparison of tumor sites, the upper outer quadrant (C) region of the 4 subregions demonstrated greater contrast enhancement on upright position images.

CONCLUSION

Clinical images obtained in an upright position with a medium-energy collimator were superior to those obtained in a supine position. Use of this procedure is recommended to enhance lymph node detection on sentinel node lymphoscintigraphy.

Use of lymphoscintigraphy defines lymphatic drainage patterns before sentinel lymph node biopsy for breast cancer

BACKGROUND

Lymphoscintigraphy (LSG) can identify lymphatic drainage patterns before sentinel lymph node (SLN) biopsy is performed in patients with early-stage breast cancer, but the importance of extraaxillary SLNs seen on LSG is unknown. We assessed whether drainage patterns seen on LSG were associated with histologic findings in axillary SLNs recovered at SLN biopsy.

STUDY DESIGN

From a prospectively maintained database, we identified 1,201 clinically node-negative patients with invasive breast cancer who underwent preoperative LSG and axillary SLN biopsy. Patient and tumor characteristics, LSG results, and final SLN pathology results were examined.

RESULTS

LSG showed drainage to internal mammary (IM) nodes in 1.6% of patients, axillary nodes in 68.1%, both IM and axillary nodes in 19.8%, and no drainage in 10.3%. Drainage to IM nodes was observed for tumors in all quadrants of the breast. Patients with IM drainage had a younger median age than patients without IM drainage (51.8 versus 58.3 years, respectively; p < 0.001). The intraoperative axillary SLN identification rate was higher when axillary drainage was observed on LSG than when it was not observed (98.7% versus 93.0%, respectively; p < 0.001), but the LSG drainage pattern was not associated with pathologic status of the SLN or number of metastatic SLNs. At a median followup of 32 months, 4 patients had regional nodal recurrence.

CONCLUSIONS

Almost one-fourth of patients had lymphatic drainage to the extraaxillary lymph nodes, particularly the IM nodes, seen on LSG. Extraaxillary drainage seen on LSG did not preclude identification of axillary SLNs at operation. Longterm followup of patients with lymphoscintigraphic evidence of extraaxillary drainage is needed to determine whether regional and systemic recurrence patterns differ in these patients.

The influence of radioisotope vehicle on breast sentinel node detection

AIM

To assess the relationship between carrier molecule size and time elapsing between marker injection and sentinel node(s) biopsy in patients with breast cancer.

MATERIAL

The study performed on 122 women, in whom the sentinel node(s) was identified according to the procedure described below. In Group I (n=72 patients), SN identification was done with radioisotope marker of 400-3000 nm molecule size (tin colloid). In Group II (n=50 patients) radioisotope marker of <100 nm molecule size (colloidal albumin) was used.

METHODS

All the patients of both groups received the markers with a single-point, intradermal, periareolar injection. Four hours after the injection (Group I - surgery in the next day) or immediately before the surgery (in this same day) (Group II), stationary lymphoscintigraphy was performed.

RESULTS

Mean numbers of sentinel nodes identified with the radioisotope method in Groups I and II were 1.22 and 1.48, respectively. The difference was statistically significant (p<0.01).

CONCLUSIONS

There is a relationship between the radioisotope marker molecule size and the injection-to-intra-operative evaluation time. Administration of small molecule size radioisotope marker several hours prior to the planned surgery appears to be the optimum procedure in this method of SN identification in patients with breast cancer.