Factors affecting sentinel lymph node detection failure in breast cancer patients using intradermal injection of the tracer

Diagnostic Value of the Sentinel Lymph Node Technique in Patients with Muscle-Invasive Bladder Cancer

BACKGROUND

The optimal limits of the bilateral pelvic lymph node dissection (PLND) template in bladder cancer treatment remain controversial. This study aimed to investigate whether radio-guided sentinel node (SLN) detection is a reliable technique for the perioperative localisation of potential lymphatic metastasis during cystectomy for muscle-invasive bladder cancer (MIBC).

MATERIALS AND METHODS

We studied 54 patients with pT2-pT4 MIBC who underwent cystectomy with extended PLND (ePLND) augmented by the SLN technique. The identification of SLN was performed by preoperative SPECT/CT hybrid lymphoscintigraphy using peritumoral injection of nanocolloid-Tc-99m, followed by intraoperative navigation with a handheld γ-probe. All nodal specimens were collected separately and then fixed in formalin, stained with haematoxylin and eosin, and examined by an experienced uropathologist.

RESULTS

A total of 1414 LNs were resected and examined for the presence of metastases. The mean number of harvested LNs was 26 (range: 11-50) per patient. In 51 of 54 patients, 192 SLNs were resected. In addition, 20/192 (10.4%) SLNs were located outside of the ePLND area. Overall, 72 metastatic LNs (LN+) were found in 22 of 54 patients (40.7%) and in 24/192 SLNs (12.5%). The SLN technique detected LN+ in 14 of 22 (64%) patients. The SLNs were the only sites of metastasis (SLN+ = LN+) in 6 of 22 (27.3%) LN+ patients, including two cases with foci located in the pararectal region. The diagnostic values for the sensitivity, specificity, positive predictive value, and false-negative rate for the SLN technique were 66.66%, 4.16%, 28.57%, and 33.33%, respectively. Extended lymphadenectomy and its combination with the SLN technique enabled the correct assessment in 96.3 and 100% of patients, respectively.

CONCLUSIONS

The combination of ePLND and SLN provides a better pN assessment compared to ePLND alone. Although the SLN technique has restrictions that limit its diagnostic value, its use as an addition to lymphadenectomy allows for the visualisation of nonstandard lymph drainage pathways that may be potential metastatic routes.

Methods of Sentinel Lymph Node Detection and Management in Urinary Bladder Cancer—A Narrative Review

Introduction: Detection of lymph node status in bladder cancer significantly impacts clinical decisions regarding its management. There is a wide range of detection modalities for this task, including lymphoscintigraphy, computed tomography, magnetic resonance imaging, single-photon emission computed tomography, positron emission tomography, and fluoroscopy. We aimed to study the pre- and intraoperative detection modalities of sentinel lymph nodes in urinary bladder cancer. Method: This narrative review was performed by searching the PubMed and EMBASE libraries using the following search terms: (“Transitional cell carcinoma of the bladder” OR “urothelial cancer” OR “urinary bladder cancer” OR “bladder cancer”) AND ((“sentinel lymph node”) OR (“lymphatic mapping”) OR (“lymphoscintigraphy”) OR (“lymphangiography”) OR (“lymph node metastases”)). Studies analysing the effectiveness and outcomes of sentinel lymph node detection in bladder cancer were included, while non-English language, duplicates, and non-article studies were excluded. After analysing the libraries and a further manual search of bibliographies, 31 studies were included in this paper. We followed the RAMESES publication standard for narrative reviews to produce this paper. Results: Of the 31 studies included, 7 studies included multiple detection methods; 5 studies included lymphoscintigraphy; 5 studies included computed tomography and/or single-photon emission computed tomography; 5 studies included fluoroscopy; 4 studies included magnetic resonance imaging; and 5 studies included positron emission tomography. Discussion: Anatomical, radioactive, and functional detection modalities have been studied independently and in combination. The consensus is that preoperative detection with imaging helps guide surgical management and intraoperative detection methods help capture any lymph nodes that may have been missed. Each of these types of detection represent their own set of benefits and drawbacks, but there is currently limited evidence to support any change in overall practice to replace conventional staging.

Repeat injection following sentinel node nonvisualization on lymphoscintigraphy images can decrease axillary dissection rate in breast cancer patients

AIM

Sentinel node biopsy is considered the standard of care in early-stage breast cancer patients. In the current study, we evaluated the effect of radiotracer reinjection in the case of sentinel node nonvisualization on preoperative lymphoscintigraphy.

MATERIALS AND METHODS

Between March 2017 and March 2020, 1850 early-stage breast cancer patients were referred for sentinel node mapping. All patients received a single injected activity of Tc-99m Phytate intradermally in the periareolar area of the index lesion using an insulin syringe. Lymphoscintigraphy images of the patients were done 1-2 h postinjection. Between March 2017 and September 2017, sentinel node nonvisualization was reported to the surgeon, and for the rest of the study period, the patients received another injected activity of the radiotracer, and immediately, other lymphoscintigraphy images were taken (with the same parameters).

RESULTS

A total of 255 patients entered our study. Fifty-five patients were in group I without any reinjection. The remainder of the patients were in group II. In 155 out of 200 patients of group II, a sentinel node could be visualized following reinjection of the radiotracer. The detection rate was 15 out of 45 and 15 out of 55 in group I and patients without sentinel node visualization even after reinjection, respectively. Axilla was involved in 5 out of 40 (12.5%) patients in group I with intraoperative sentinel node mapping failure. On the other hand, axilla was involved in 27 out of 30 (90%) group II patients with sentinel node nonvisualization.

CONCLUSION

Reinjection of the tracer in cases of no sentinel node visualization in lymphoscintigraphy for breast cancer increases the detection rate of sentinel nodes, and therefore a high number of unnecessary axillary lymph node dissections can be avoided.

Lymphoscintigraphy in the Time of COVID-19: Effect of Molybdenum-99 Shortage on Feasibility of Sentinel Node Mapping

Background: In the current study, we reported our experience on sentinel node mapping of breast cancer patients during the extreme shortage of Mo99-Tc99m generators using Tc-99m phytate. Methods and Results: During the period from March 7, 2019, to April 18, 2020, due to disruption of molybdenum supply chain, we used low specific activity Tc-99m pertechnetate elute (0.5-2 mCi of ^99mTcO₄ in 5 mL) for each kit preparation. Two or three intradermal periareolar injections were done for each patient (0.02-0.1 mCi/0.2 mL for each injection). Immediately following injection, dynamic lymphoscintigraphy was done. Surgery was done the same day of injection and the axillary sentinel node was sought using a gamma probe. Overall, 35 patients were included in the study. The specific activity of the Tc-99m elute (in 5 mL) used for kit preparation was 2 mCi/10 mg in four, 1.5 mCi/10 mg in eight, 1.25 mCi/10 mg in eight, 1 mCi/10 mg in three, 0.75 mCi/10 mg in five, and 0.5 mCi/10 mg of ^99mTc-Phytate in seven patients. For the first four groups of patients, we used two 0.2 mL injections, while in the latter two groups, three 0.2 mL injections were used. At least one sentinel node was detected in all patients but three in whom axilla was involved. Conclusion: Sentinel node biopsy can be achieved with low specific activity of Tc-99m elute at the time of Mo99-Tc-99m generator shortage. If special personal protection is used, sentinel node mapping can be done in nuclear medicine departments with excellent results despite the COVID-19 pandemic and disruption of generator shipment.

Sentinel lymph node biopsy in muscle-invasive bladder cancer: single-center experience

OBJECTIVE

In this study, the validity of sentinel node biopsy procedure as our index test was assessed and compared with bilateral pelvic lymphadenectomy for staging and detecting the regional lymph nodes metastasis in patients with muscle-invasive bladder cancer (MIBC).

METHODS

Consecutive series of cases with T1-T4 urothelial MIBC were included. Following the injection of radiotracer, sentinel nodes were sought using a handheld gamma probe and all hot nodes were harvested. Bilateral pelvic lymphadenectomy was done for all patients following sentinel node biopsy. The tumor specimen, sentinel nodes, and excised lymph nodes were evaluated histopathologically. Same as the other midline tumors, detection rate and false negative rates were calculated using patient basis and side basis methods.

RESULTS

By evaluating each patient as a unit of analysis, sentinel nodes were detected in 35 of 41 patients (85%), 13/16 (81%) of the neoadjuvant chemotherapy (NAC) and 22/25 (88%) of the no-neoadjuvant chemotherapy (No-NAC) participants. The false negative rate was 3/7 (42%): 1/3 (33%) for NAC, and 2/4 (50%) for No-NAC patients. By evaluating each hemipelvis as a unit of analysis, sentinel nodes were detected in 53 of 82 hemipelves (65%), 19/32 (66%) of the NAC, and 34/50 (68%) of the No-NAC hemipelves. No false-negative result was found by assessing each hemipelvis as a unit of analysis.

CONCLUSIONS

Sentinel node biopsy is a feasible method for lymph node staging in MIBC, including patients with a history of NAC. To optimize the sensitivity, the decision regarding the lymphadenectomy is best to be based on the pathological status of sentinel node harvested from each hemipelvis separately as the unilateral finding of a sentinel node, does not rule out the possibility of metastatic involvement of contralateral pelvic lymph nodes.

Progress in Animal Models of Pancreatic Ductal Adenocarcinoma

As a common gastrointestinal tumor, the incidence of pancreatic cancer has been increasing in recent years. The disease shows multi-gene, multi-step complex evolution from occurrence to dissemination. Furthermore, pancreatic cancer has an insidious onset and an extremely poor prognosis, so it is difficult to obtain cinical specimens at different stages of the disease, and it is, therefore, difficult to observe tumorigenesis and tumor development in patients with pancreatic cancer. At present, no standard protocols stipulate clinical treatment of pancreatic cancer, and the benefit rate of new targeted therapies is low. For this reason, a well-established preclinical model of pancreatic cancer must be established to allow further exploration of the occurrence, development, invasion, and metastasis mechanism of pancreatic cancer, as well as to facilitate research into new therapeutic targets. A large number of animal models of pancreatic cancer are currently available, including a cancer cell line-based xenograft, a patient-derived xenograft, several mouse models (including transgenic mice), and organoid models. These models have their own characteristics, but they still cannot perfectly predict the clinical outcome of the new treatment. In this paper, we present the distinctive features of the currently popular pancreatic cancer models, and discuss their preparation methods, clinical relations, scientific purposes and limitations.

Lymphatic mapping and sentinel node biopsy in ovarian tumors: a study using intra-operative Tc-99m-Phytate and lymphoscintigraphy imaging

Background

Experience on sentinel node mapping in ovarian tumors is very limited. We evaluated the sentinel node concept in ovarian tumors using intra-operativeTc-99m-Phytate injection and lymphoscintigraphy imaging.

Methods

Thirty-five patients with a pelvic mass due to an ovarian pathology were included in the study. The radiotracer was injected just after laparotomy and before removal of the tumor either beneath the normal cortex (10 patients) or in the utero-ovarian and suspensory ligaments of the ovary just beneath the peritoneum two injections of the radiotracer (25 patients). For malignant masses, the sentinel nodes were identified using a hand held gamma probe. Then standard pelvic and para-aortic lymphadenectomy was performed. In case of benign pathologies or borderline ovarian tumors on frozen section, lymphadenectomy was not performed. The morning after surgery, all patients were sent for lymphoscintigraphy imaging of the abdomen and pelvis.

Results

Sentinel node was identified only in 4 patients of the cortical injection group. At least one sentinel node could be identified in 21 patients of the sub-peritoneal group. Sentinel nodes were identified only in the para-aortic area in 21, pelvic/para-aortic areas in 2, and pelvic only area in 2 patients. Three patients had lymph node involvement and all had involved sentinel nodes (no false negative case).

Conclusion

Sentinel node mapping using intra-operative injection of the radiotracer (in the utero-ovarian and suspensory ligaments of the ovary just beneath the peritoneum) is feasible in ovarian tumors. Technical aspects of this method should be explored in larger multicenter studies in the future.

Preoperative Scintigrams to Identify the Sentinel Lymph Node in Breast Cancer: a Waste of Time?

Sentinel lymph node biopsy (SLNB) remains the gold standard for assessing axillary node status in breast cancer. Preoperative scintigrams have been used to identify the sentinel lymph node (SLN); however, their use is controversial. Studies suggest they add little to successful SLN detection in theatre, immediately prior to node excision. They have been associated with high false negatives, time expense, patient dissatisfaction, and unnecessary costs. The aim of the present study was to evaluate the diagnostic accuracy of scintigrams in comparison to intraoperative SLN identification techniques. This study included all patients undergoing a SLNB for breast cancer from April 2010 to 2011. Scintigram reports, operation notes, and histology results were analyzed. Mann-Whitney U and chi-squared tests were used for statistical analysis of data. Two hundred nineteen female patients with a median age of 59.6 years (24.0-89.9 years) were included in this study. Scintigram was performed in 185 and not in 34 patients due to time constraints. Combined γ-probe and Isosulfan blue dye for SLN detection (intraoperative methods) have an identification rate of 98.2 % (p = 0.005), compared to 92.4 % (p = 0.088) from scintigrams alone. Scintigrams confer no additional advantage to the operating surgeon for successful SLN detection and excision in theatre. Intraoperative SLN identification is more accurate and reliable. Routine scintigram use is unjustified and should be withdrawn from current practice.

Characterization of the role of the photosensitizer, deuteporfin, in the detection of lymphatic metastases in a pancreatic cancer xenograft model

Currently, the use of photosensitizers as tracer agents to detect lymphatic metastases is a developing area of study in the field of pancreatic cancer treatment. In the present study, deuteporfin, a novel photosensitizer, was used as a tracer agent to detect lymphatic metastases in a pancreatic cancer xenograft model. The biodistribution and pharmacokinetics of deuteporfin, following intravenous administration and injection of deuteporfin into the left rear footpad, were investigated in Sprague-Dawley rats. The increased difference in deuteporfin concentration between the cancerous and normal tissues was directly observed through the application of a Wood's lamp. In addition, the highly lymphatic BxPC-3-LN5 human metastatic pancreatic cancer cell line was generated from BxPC-3 cells using a continuous screening and seeding method in vivo. A xenograft model of the BxPC-3-LN5 human pancreatic cancer cell line transplanted into the left rear footpad of nude mice, was established. The effects of deuteporfin as a tracer agent in the detection of lymphatic metastases were then characterized in the pancreatic cancer xenograft model. Following intravenous administration, deuteporfin was rapidly enriched in the pancreas and popliteal fossa lymph nodes compared with that of the left rear footpad administration group. In addition, deuteporfin appeared to be selectively enriched in the cancerous pancreatic lymph nodes of the pancreatic cancer xenograft model. These results indicated that deuteporfin may be developed as a novel photosensitizer tracer agent for the detection of lymphatic metastases in pancreatic cancer. The advantages of deuteporfin are that it has a selective tumor-targeting effect due to high tissue uptake, and that it may be administered intravenously and is therefore suitable for surgery.

Breast cancer lymphoscintigraphy: Factors associated with sentinel lymph node non visualization

OBJECTIVE

To evaluate factors associated with non identification of the sentinel lymph node (SLN) in lymphoscintigraphy of breast cancer patients and analyze the relationship with SLN metastases.

MATERIAL AND METHODS

A single-center, cross-sectional and retrospective study was performed. Forty patients with lymphoscintigraphy without sentinel lymph node identification (negative lymphoscintigraphy - NL) were enrolled. The control group included 184 patients with SLN identification (positive lymphoscintigraphy - PL). Evaluated factors were age, body mass index (BMI), tumor size, histology, localization, preoperative breast lesion hookwire (harpoon) marking and SLN metastases. The statistical analysis was performed with uni- and multivariate logistic regression models and matched-pairs analysis.

RESULTS

Age (p=0.036) or having BMI (p=0.047) were the only factors significantly associated with NL. Being ≥60 years with a BMI ≥30 increased the odds of having a NL 2 and 3.8 times, respectively. Marking with hookwire seems to increase the likelihood of NL, but demonstrated statistical significance is lacking (p=0.087). The other tested variables did not affect the examination result. When controlling for age, BMI and marking with the harpoon, a significant association between lymph node metastization and NL was not found (p=0.565).

CONCLUSIONS

The most important factors related with non identification of SLN in the patients were age, BMI and marking with hook wire. However, only the first two had statistical importance. When these variables were controlled, no association was found between NL and axillary metastases.

[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.

Sentinel node biopsy for lymph nodal staging of uterine cervix cancer: a systematic review and meta-analysis of the pertinent literature

BACKGROUND

We reviewed the available literature on the accuracy of sentinel node mapping in the lymph nodal staging of uterine cervical cancers.

METHODS

MEDLINE and Scopus were searched by using "sentinel AND (cervix OR cervical)" as key words. Studies evaluating the accuracy of sentinel node mapping in the lymph nodal staging of uterine cervical cancers were included if enough data could be extracted for calculation of detection rate and/or sensitivity.

RESULTS

Sixty-seven studies were included in the systematic review. Pooled detection rate was 89.2% [95% CI: 86.3-91.6]. Pooled sensitivity was 90% [95% CI: 88-92]. Sentinel node detection rate and sensitivity were related to mapping method (blue dye, radiotracer, or both) and history of pre-operative neoadjuvant chemotherapy. Sensitivity was higher in patients with bilaterally detected pelvic sentinel nodes compared to those with unilateral sentinel nodes. Lymphatic mapping could identify sentinel nodes outside the routine lymphadenectomy limits.

CONCLUSION

Sentinel node mapping is an accurate method for the assessment of lymph nodal involvement in uterine cervical cancers. Selection of a population with small tumor size and lower stage will ensure the lowest false negative rate. Lymphatic mapping can also detect sentinel nodes outside of routine lymphadenectomy areas providing additional histological information which can improve the staging. Further studies are needed to explore the impact of sentinel node mapping in fertility sparing surgery and in patients with history of neoadjuvant chemotherapy.

Added value of blue dye injection in sentinel node biopsy of breast cancer patients: do all patients need blue dye?

BACKGROUND

In the current study, we evaluated the incremental value of blue dye injection in sentinel node mapping of early breast cancer patients. We specially considered the experience of the surgeons and lymphoscintigraphy results in this regard.

METHODS

605 patients with early stage breast cancer were retrospectively evaluated in the study. Patients underwent sentinel node mapping using combined radiotracer and blue dye techniques. Lymphoscintiraphy was also performed for 590 patients. Blue dye, radioisotope, and overall success rates in identifying the sentinel lymph node were evaluated in different patient groups. The benefit of blue dye and radioisotope in identifying the sentinel lymph nodes was also evaluated.

RESULTS

Marginal benefits of both blue dye and isotope for overall sentinel node detection as well as pathologically involved sentinel nodes were statistically higher in inexperienced surgeons and in patients with sentinel node visualization failure. In the patients with sentinel node visualization on lymphoscintigraphy, 6 sentinel nodes were detected by blue dye only. All these six nodes were harvested by inexperienced surgeons. On the other hand 8 sentinel nodes were detected by dye only in the patients with sentinel node non-visualization. All these nodes were harvested by experienced surgeons.

CONCLUSIONS

The use of blue dye should be reserved for inexperienced surgeons during their learning phase and for those patients in whom lymphoscintigraphy failed to show any uptake in the axilla.

[Sentinel node biopsy in patients with multifocal and multicentric breast cancer: A 5-year follow-up]

OBJECTIVE

Sentinel lymph node biopsy (SLNB) as a staging procedure in multiple breast cancer is a controversial issue. We have aimed to evaluate the efficacy of sentinel node (SN) detection in patients with multifocal or multicentric breast cancer as well as the safety of its clinical application after a long follow-up.

MATERIAL AND METHODS

A prospective descriptive study was performed. Eighty-nine patients diagnosed of multiple breast cancer (73 multifocal; 16 multicentric) underwent SLNB. These patients were compared to those with unifocal neoplasia. Periareolar radiocolloid administration was performed in most of the patients. Evaluation was made at an average of 67.2 months of follow-up (32-126 months).

RESULTS

Scintigraphic and surgical SN localization in patients with multiple breast cancer were 95.5% and 92.1%, respectively. A higher percentage of extra-axillary nodes was observed than in the unifocal group (11.7% vs 5.4%) as well as a significantly higher number of SN per patient (1.70 vs 1.38). The rate of SN localization in multicentric cancer was slightly lower than in multifocal cancer (87.5% vs 93.1%), and the finding of extra-axillary drainages was higher (20% vs 10%). Number of SN per patient was significantly higher in multicentric breast cancer (2.33 vs 1.57). No axillary relapses have been demonstrated in the follow-up in multiple breast cancer patients group.

CONCLUSIONS

SLNB performed by periareolar injection is a reliable and accurate staging procedure of patients with multiple breast cancer, including those with multicentric processes.

Accuracy of sentinel node biopsy in esophageal carcinoma: a systematic review and meta-analysis of the pertinent literature

The use of sentinel node surgery for esophageal carcinoma is still under investigation. We evaluated the data available in the literature on this topic, and herein present the results in a systematic review format. PUBMED, SCOPUS, the ISI web of knowledge and the information from the annual meetings of the Japan Esophageal Society were searched using the search terms: "(esophagus OR esophageal) AND sentinel". The outcomes of interest were the detection rate and sensitivity. Overall, 18 studies were included. The pooled detection rate was 89.2% [82.6-93.5]. Patients with T1 and two tumors had a 17% higher detection rate compared to those with T3 and four tumors. The pooled sensitivity was 84% [78-88%]. The sensitivity was higher for adenocarcinoma compared to squamous cell carcinoma (SCC) (91 vs. 81%). In the SCC patients, there was a trend toward decreased sensitivity associated with an increasing tumor depth (T1:88%, T2:76%, T3:50%). Our analysis indicated that sentinel node biopsy is useful in adenocarcinoma patients. For SCC patients, including only cN0 patients (preferably T1 and 2) would increase the detection rate and sensitivity. Due to the limited number of high-quality studies, drawing any more definite conclusions is impossible. Large cohort studies with a standardized and consistent design will be needed in the future.

Accuracy of sentinel node biopsy in the staging of non-small cell lung carcinomas: systematic review and meta-analysis of the literature

BACKGROUND

Not all patients with non-small cell lung carcinoma (NSCLC) have mediastinal lymph node involvement and development of less invasive methods for evaluating mediastinal lymph nodes is important. Sentinel node biopsy has been used for NSCLC since 1999 to decrease the need for mediastinal lymph node dissection. In this review, we searched the literature in this regard and reported the results in a meta-analysis format.

METHODS

Medline, SCOPUS, and ISI web of knowledge were searched using: "(lung AND sentinel)" with no date or language limit. Any study with more than 5 patients and enough information to calculate detection rate and sensitivity was included.

RESULTS

Overall 47 and 43 studies (including subgroups) had the criteria for detection rate and sensitivity pooling respectively. Pooled detection rate was 80.6% [76.8-84%] and pooled sensitivity was 87% [83-90%]. Using radiotracers or both radiotracers and dyes had higher detection rate and sensitivity compared to dye alone. Among studies using radiotracers, highest detection rate was in intra-operative peri-tumoral injection group and highest sensitivity was in peri-tumoral pre-operative injection group. Emerging methods of sentinel node surgery including magnetic materials, fluorescent dyes, CT contrast agents, and carbon nano-particles had promising results.

CONCLUSIONS

Sentinel node mapping using radiotracers is a feasible technique for mediastinal lymph node staging of N0 NSCLC patients. Alternative methods of sentinel node mapping are promising and warrant further studies.

Value of sentinel lymph node biopsy in breast cancer surgery with simple pathology facilities--an Iranian local experience with a review of potential causes of false negative results

INTRODUCTION

Sentinel lymph node biopsy (SLNB) is a precise procedure for lymphatic staging in early breast cancer. In a valid SLNB procedure, axillary lymph node dissection (ALND) can be omitted in node- negative cases without compromising patient safety. In this study, detection rate, accuracy and false negative rate of SLNB for breast cancer was evaluated in a setting with simple modified conventional pathology facilities without any serial sectioning or immunohistochemistry.

MATERIAL AND METHOD

Patients with confirmed breast cancer were enrolled in the study. SLNB and ALND were performed in all cases. Lymph node metastasis was evaluated in SLN and in nodes removed by ALND to determine the false negative rate. Pathologic assessment was carried out only by modified conventional technique with only 3 sections. Detection rate was determined either by lymphoscintigraphy or during surgery.

RESULTS

78 patients with 79 breast units were evaluated. SLN was detected in 75 of 79 cases (95%) in lymphoscintigraphy and 76 of 79 cases (96%) during surgery. SLN metastases was detected in 30 of 75 (40%) cases either in SLNB and ALND groups. Accuracy of SLNB method for detecting LN metastases was 92%. False negative rate was 3 of 30 of positive cases: 10%. In 7 of 10 cases with axillary lymphadenopathy, LN metastastates was detected.

CONCLUSION

SLNB is recommended for patients with various tumor sizes without palpable lymph nodes. In modified conventional pathologic examination of SLNs, at least macrometastases and some micrometastases could be detected similar to ALND. Consequently, ALND could be omitted in node-negative cases with removal of all palpable LNs. We conclude that SLNB, as one of the most important developments in breast cancer surgery, could be expanded even in areas without sophisticated pathology facilities.

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.

Efficacy of high-energy collimator for sentinel node lymphoscintigraphy of early breast cancer patients

INTRODUCTION

Lymphoscintigraphy is an important part of sentinel node mapping in breast cancer patients. Sometimes star shaped artefacts due to septal penetration can be problematic during imaging. In the current study, we evaluated the possibility of high energy (HE) collimators use for lymphoscintigraphy.

PATIENTS AND METHODS

Twenty patients with early breast carcinoma were included. Thirty minutes after radiotracer injection (99mTc-antimony sulphide colloid), anterior and lateral images were acquired using a dual head gamma camera equipped with a parallel hole low energy high resolution (LEHR) collimator on one head and HE collimator on another head. All images were reviewed by two nuclear medicine specialists regarding detectability and number of axillary sentinel nodes and presence of star artefact.

RESULTS

All images taken by LEHR collimators showed star artefact of the injection site. No image taken by HE collimator showed this effect. In two patients the sentinel node was visible only by HE collimator. Tumour location in both of these patients was in the upper lateral quadrant and both had history of excisional biopsy. In two patients additional sentinel node was visible adjacent to the first one only on the LEHR images.

CONCLUSIONS

HE collimators can be used for sentinel lymph node mapping and lymphoscintigraphy of the breast cancer patients. This collimator can almost eliminate star-shaped artefacts due to septal penetration which can be advantageous in some cases. However, to separate two adjacent sentinel nodes from each other LEHR collimators perform better.

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 in patients with operable breast cancer treated with neoadjuvant chemotherapy

AIM

To evaluate the accuracy of sentinel lymph node biopsy (SLNB) in operable breast cancer patients treated with neoadjuvant chemotherapy (NAC).

MATERIALS AND METHODS

Between January 2008-2011, 88 women, mean age 49.4 years, with infiltrating breast carcinoma, were studied prospectively. Patients were T1-3, N0-1, M0. Prior to surgery, the patients received chemotherapy (epirubicin/cyclophosphamide, docetaxel), and trastuzumab in Her2/neu-positive patients. Axillary status was established by physical examination, ultrasound-guided core needle biopsy of any suspicious lymph node. The day before surgery, 74-111 MBq of (99m)Tc-albumin nanocolloid was injected periareolarly. All patients underwent breast surgery, with SLNB, followed by complete axillary lymph node dissection (ALND). Sentinel lymph node (SLN) were examined by frozen sections, hematoxylin-eosin staining and immunohistochemical analysis or One Step Nucleic Acid Amplification (OSNA).

RESULTS

Mean tumor size: 3.5 cm. Histologic type: 69 invasive ductal, 16 invasive lobular and 3 others. Thirty seven patients had clinical/ultrasound node-positive at presentation. Clinical response of primary tumor to NAC: complete in 38, partial in 45, and stable disease in 5 patients. A pathological complete response was achieved in 25. All patients were clinically node-negative after NAC. SLN identification rate was 92.0%. Six of 7 patients in whom SLN was not found had clinical/ultrasound positive axilla before NAC. SLN accurately determined the axillary status in 96.5%. False negative rate was 8.3%. In 69.4% of patients, SLN was the only positive node. The mean number of SLN removed was 1.7 and nodes resected from the ALND were 13.2.

CONCLUSION

SLN biopsy after NAC can predict the axillary status with a high accuracy in patients with breast cancer, avoiding unnecessary ALND.

Scatterogram: a method for outlining the body during lymphoscintigraphy without using external flood source

Background

We evaluated the feasibility of outlining the body with scattered photons using a low dose intradermal injection of the radiotracer.

Patients and methods.

Sixty breast cancer patients were included into the study. 30 minutes post radiotracer injection static lymphoscintigraphy images were acquired using low energy high resolution collimator in anterior and lateral views. For patients with 2-day protocol another set of images was taken 20 hours post-injection. Two photopeaks were used during imaging: 1-Tc-99m (130-150 keV) and 2- Scatter photons (60-120). The fusion image of these two images was constructed by NM-NM fusion workflow of the workstation. The usual body outline of the patients was also acquired in 20 cases using the external flood source without moving the patients from their positions.

Results

The early (30 minute image) scatterograms of the patients clearly showed the contour of the body. The 20 hour scatterograms were not as high quality as the corresponding early images. The constructed overlaid images showed the location of the axillary sentinel nodes and the body contours clearly for early scatterograms but not the delayed (20 hour) ones. The processing of the images for the reconstruction of overlaid scatterograms took the mean time of 10±5 seconds.

Conclusions

Imaging the scattered photons is feasible for the intradermal low dose injection of the radiotracers in order to outline the body contour. This imaging method does not increase the radiation exposure of the patients or operators and does not extend the time of imaging either.