Detection of lymph node metastasis with near-infrared upconversion luminescent nanoprobes

The detection of lymph node metastasis is of great importance for therapy planning and prognosis of cancers, but remains challenging in the clinic. In the current study, we report a tumor-specific imaging probe constructed with NaGdF4:Yb,Tm,Ca@NaLuF4 core@shell upconversion nanoparticles showing distinctive near infrared emission. The following studies revealed that the characteristic Tm dopant emission at 804 nm showed a penetration depth up to 7.7 mm through multi-layered mice skin tissues, substantially greater than emissions at 655 nm and 541 nm typically from the widely used Er dopant, which is apparently favorable for sensitive tumor diagnosis. The cell binding assay further revealed that the anti-HER2 antibodies covalently attached on the particle surface endowed the nanoprobe with excellent binding specificity in targeting HER2-positive cancer cells in vitro, which further enabled the detection of lymph node metastasis of breast cancer in vivo in mice. In addition, the pharmacokinetics of the resulting nanoprobes were intensively studied through both upconversion luminescence imaging and SPECT imaging for comparing with that of the mother particles. The results obtained through both approaches were well consistent and revealed that the surface conjugation of antibodies largely altered the pharmacokinetic behaviors and substantially prolonged the blood half-life of the underlying nanoparticles, which was never reported before.

Sentinel lymph node biopsy under fluorescent indocyanin green guidance: Initial experience

OBJECTIVE

Sentinel lymph node biopsy can be applied by using either blue dye or radionuclide method or both in breast cancer. Fluorescent imaging with indocyanine green is a new defined method. This study evaluates the applicability of sentinel lymph node biopsy via fluorescent indocyanine green.

MATERIAL AND METHODS

IC-VIEW (Pulsion Medical Systems AG, Munich, Germany) infrared visualization system was used for imaging. Two mL of indocyanine green was injected to visualize sentinel lymph nodes. After injection, subcutaneous lymphatics were traced and sentinel lymph nodes were found with simultaneous imaging. Sentinel lymph nodes were excised under fluorescent light guidance, and excised lymph nodes were examined histopathologically. Patients with sentinel lymph node metastases underwent axillary dissection.

RESULTS

Four patients with sentinel lymph node biopsy due to breast cancer were included in the study. Sentinel lymph nodes were visualized with indocyanine green in all patients. The median number of excised sentinel lymph node was 2 (2-3). Two patients with lymph node metastasis underwent axillary dissection. No metastasis was detected in lymph nodes other than the sentinel nodes in patients with axillary dissection. There was no complication during and after the operation related to the method.

CONCLUSION

According to our limited experience, sentinel lymph node biopsy under fluorescent indocyanine green guidance, which has an advantage of simultaneous visualization, is technically feasible.

The role of general nuclear medicine in breast cancer

The rising incidence of breast cancer worldwide has prompted many improvements to current care. Routine nuclear medicine is a major contributor to a full gamut of clinical studies such as early lesion detection and stratification; guiding, monitoring, and predicting response to therapy; and monitoring progression, recurrence or metastases. Developments in instrumentation such as the high-resolution dedicated breast device coupled with the diagnostic versatility of conventional cameras have reinserted nuclear medicine as a valuable tool in the broader clinical setting. This review outlines the role of general nuclear medicine, concluding that targeted radiopharmaceuticals and versatile instrumentation position nuclear medicine as a powerful modality for patients with breast cancer.

Blue dye is sufficient for sentinel lymph node biopsy in breast cancer

BACKGROUND

Most previous studies have reported superior results when blue dye and radiocolloids were used together for sentinel lymph node (SLN) biopsy in early breast cancer. Blue dye was reported to perform poorly when used alone, although more recent studies have found otherwise. This study reviewed the authors' practice of performing SLN biopsy with blue dye alone.

METHODS

This was a retrospective review of patients who underwent SLN biopsy using blue dye alone from 2001 to 2005, when SLN biopsy was performed selectively and always followed by axillary lymph node dissection (ALND), and from 2006 to 2010, when SLN biopsy was offered to all suitable patients and ALND done only when the SLN was not identified or positive for metastasis.

RESULTS

Between 2001 and 2005, 170 patients underwent SLN biopsy with blue dye alone. The overall SLN non-identification rate was 8·4 per cent. The overall false-negative rate was 34 per cent, but decreased with each subsequent year to 13 per cent in 2005. From 2006 to 2010, 610 patients underwent SLN biopsy with blue dye alone. The SLN was not identified in 12 patients (2·0 per cent) and no significant contributing factor was identified. A median of 2 (range 1-11) SLNs were identified. A non-SLN was found to be positive for metastasis in two patients with negative SLNs. Axillary nodal recurrence developed in one patient; none developed internal mammary nodal recurrence. Anaphylaxis occurred in one patient.

CONCLUSION

Blue dye performed well as a single modality for SLN biopsy. Non-identification, axillary nodal recurrence and serious allergic reactions were uncommon.

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.

Minimally invasive surgery for esophageal cancer: a review on sentinel node concept

BACKGROUND

Lymphoadenectomy is a cornerstone of esophageal cancer treatment, and sentinel node (SN) biopsy (SNB) might provide surgeons with an extra tool to limit unnecessarily extended lymphadenectomy and to implement a minimally invasive approach. The aim of our study was to review all the available literature on the use of SNB in esophageal surgery for malignancy.

METHODS

The review was conducted according to the PRISMA guidelines. A systematic search was performed in PubMed, EMBASE, and the Cochrane database to identify all original articles on the role of SNB in esophageal cancer. Data on methodologies, tumor stage and localization, and results were summarized and used to address relevant clinical questions related to the application of the SNB technique in esophageal cancer.

RESULTS

Twelve studies were included, with a total of 492 patients. Different methods for SN identification were used (radionuclide, blue dye, computed tomography [CT] lymphography). The pooled values estimated using the random-effects model were, respectively: technetium-99 m overall detection rate (DR) 0.970 (95 % CI 0.814-0.996), accuracy (ACC) 0.902 (95 % CI 0.736-0.968); blue-dye DR 0.971 (95 % CI 0.890-0.993), ACC 0.790 (95 % CI 0.681-0.870); and CT lymphoscintigraphy DR 0.970 (95 % CI 0.814-0.996), ACC 0.902 (95 % CI 0.736-0.968).

CONCLUSION

Based on these results, the concept of SN in esophageal cancer is technically feasible with an acceptable DR and ACC, and it might be applicable in the event of early-stage adenocarcinoma of the gastroesophageal junction in patients with a high surgical risk or in a patient where an endoscopic resection is taken into consideration. Further studies focused on a single tumor type and localizations are needed in order to predict the correct utilization of this concept in minimally invasive treatment of esophageal cancer.

Novel diagnostic procedure for determining metastasis to sentinel lymph nodes in breast cancer using a semi-dry dot-blot method

We developed an easy, quick and cost-effective detection method for lymph node metastasis called the semi-dry dot-blot (SDB) method, which visualizes the presence of cancer cells with washing of sectioned lymph nodes by anti-pancytokeratin antibody, modifying dot-blot technology. We evaluated the validity and efficacy of the SDB method for the diagnosis of lymph node metastasis in a clinical setting (Trial 1). To evaluate the validity of the SDB method in clinical specimens, 180 dissected lymph nodes from 29 cases, including breast, gastric and colorectal cancer, were examined. Each lymph node was sliced at the maximum diameter and the sensitivity, specificity and accuracy of the SDB method were determined and compared with the final pathology report. Metastasis was detected in 32 lymph nodes (17.8%), and the sensitivity, specificity and accuracy of the SDB method were 100, 98.0 and 98.3%, respectively (Trial 2). To evaluate the efficacy of the SDB method in sentinel lymph node (SLN) biopsy, 174 SLNs from 100 cases of clinically node-negative breast cancer were analyzed. Each SLN was longitudinally sliced at 2-mm intervals and the sensitivity, specificity, accuracy and time required for the SDB method were determined and compared with the intraoperative pathology report. Metastasis was detected in 15 SLNs (8.6%), and the sensitivity, specificity, accuracy and mean required time of the SDB method were 93.3, 96.9, 96.6 and 43.3 min, respectively. The SDB method is a novel and reliable modality for the intraoperative diagnosis of SLN metastasis.

Sentinel node in ovarian cancer: study protocol for a phase 1 study

Background

The concept of sentinel lymph node surgery is to determine whether the cancer has spread to the very first lymph node or sentinel node. If the sentinel node does not contain cancer, then there is a high likelihood that the cancer has not spread to other lymph nodes. The sentinel node technique has been proven to be effective in different types of cancer. In this study we want to determine whether a sentinel node procedure in patients with ovarian cancer is feasible when the tracers are injected into the ovarian ligaments.

Methods/Design

Patients with a high likelihood of having an ovarian malignancy in whom a median laparotomy and a frozen section analysis is planned and patients with endometrial cancer in whom a staging laparotomy is planned will be included.

Before starting the surgical staging procedure, blue dye and radioactive colloid will be injected into the ligamentum ovarii proprium and the ligamentum infundibulo-pelvicum. In the analysis we calculate the percentage of patients in whom it is feasible to identify sentinel nodes. Other study parameters are the anatomical localization of the sentinel node(s) and the incidence of false negative lymph nodes.

Trial registration

Approval number: NL40323.068.12

Name: Medical Ethical Committee Maastricht University Hospital, University of Maastricht

Affiliation: Maastricht University Hospital

Board Chair Name: Medisch Ethische Commissie azM/UM

Multimodal sentinel lymph node mapping with single-photon emission computed tomography (SPECT)/computed tomography (CT) and photoacoustic tomography

The identification of cancer cells in the lymph nodes surrounding a tumor is important in establishing a prognosis. Optical detection techniques such as fluorescence and photoacoustic tomography (PAT) have been reported in preclinical studies for noninvasive sentinel lymph node (SLN) mapping. A method for validation of these techniques is needed for clinical trials. We report the use of a multimodal optical-radionuclear contrast agent as a validation tool for PAT in a preclinical model. Methylene blue (MB) was radiolabeled with (125)I for multimodal SLN mapping and used in conjunction with MB to assess the feasibility of multimodal SLN mapping in a rat model by PAT and single-photon emission computed tomography (SPECT). MB provided sufficient contrast for identifying SLNs noninvasively with a PAT system adapted from a clinical ultrasound imaging system. The signal location was corroborated by SPECT using (125)I labeled MB. The translation of PAT into the clinic can be facilitated by a direct comparison with established imaging methods using a clinically relevant dual SPECT and photoacoustic imaging agent. The new high-resolution PAT is a promising technology for the sensitive and accurate SLN detection in cancer patients.

Sentinel lymph node biopsy in esophageal cancer: should it be standard of care?

INTRODUCTION

Sentinel node mapping is established in some superficial cancers but remains controversial in harder-to-access solid tumors. There are an increasing number of recent studies suggesting that isolated tumor cells have prognostic significance in predicting poor survival, in breast cancer, esophageal cancer, and others. It is for this reason that we have persevered with the sentinel lymph node concept in our esophagectomy cancer patients, and we report our results since 2008.

METHODS

Thirty-one of 32 consecutive patients underwent resection for invasive esophageal cancer along with sentinel lymph node retrieval (resection rate, 97%). Peritumoral injection of (99m)Tc antimony colloid was performed by upper endoscopy prior to the operation. A two-surgeon synchronous approach via a right thoracotomy and laparotomy was performed with a conservative lymphadenectomy. Sentinel lymph nodes were identified with a gamma probe both in and ex vivo, and sent off separately for three serial sections and immunohistochemistry with AE1/AE3.

RESULTS

The median patient age was 63.4 years (range, 45-75 years). Most patients (81%) had an adenocarcinoma, and 61% had received neoadjuvant therapy. At least one sentinel lymph node (median, 3) was identified in 29 of 31 patients (success rate, 94%). Sentinel nodes were present in more than one nodal station in 16 patients (55%). One false negative case led to a sensitivity of 90%. In 28 of 29 patients, the sentinel lymph node accurately predicted findings in non-sentinel nodes (accuracy, 96%).

CONCLUSIONS

Sentinel lymph node biopsy is both feasible and accurate in esophageal resections with conservative lymphadenectomy. It allows targeted serial sectioning and immunohistochemical studies of those nodes and should become standard of care in patients undergoing esophagectomy for esophageal cancer.

Tracer-cocktail injections for combined pre- and intraoperative multimodal imaging of lymph nodes in a spontaneous mouse prostate tumor model

To improve surgical guidance toward prostate draining lymph nodes, we investigate the potential of intraoperative fluorescence imaging and combined pre- and intraoperative multimodality imaging approaches. Transgenic adenocarcinoma mouse prostate mice with spontaneous prostate tumors are injected intratumorally with: 1. a cocktail of patent blue (Pb) and indocyanine green (ICG); 2. a cocktail of albumin radiocolloids (99mTc-NanoColl), Pb, and ICG; or 3. a cocktail of radiolabeled albumin (99mTc-Vasculosis), Pb, and ICG. The distribution of these imaging agents over the lymph nodes (LNs) are studied at different time points after injection. We find that at 60-min postinjection, ICG significantly improves the detection of the LNs compared to Pb, 53 versus 7%, respectively. Moreover, a cocktail of ICG and 99mTc-NanoColl improves the fluorescent detection rate to 86%, equalling that of the clinically applied 99mTc-NanoColl. A similar overlap is observed in our initial clinical pilot data. Fluorescent detection of the LNs using a ICG with 99mTc-Vasculosis gives similar results as "free" ICG (58%; 60 min). A 99mTc-NanoColl, Pb, and cocktail ICG enriches the standard 99mTc-NanoColl approach by adding optical detection of the sentinel lymph nodes. Furthermore, this approach improves fluorescent-based guidance and enables both accurate surgical planning and intraoperative detection, based on a single injection.