Sentinel Lymph Node Detection Research Articles

Advances in surgical techniques for gastric cancer: Indocyanine green and near-infrared fluorescence imaging. Is it ready for prime time?

Surgery is still the primary curative treatment for gastric cancer, which includes resection of the tumor with adequate margins and extended lymphadenectomy. In order to improve the operative results and the quality of life of patients, several endeavors have been made toward precision medicine through image-guided surgery, allowing access to real-time intraoperative anatomy and accurate tumor staging. The goal of the surgeon is to achieve a more precise, individualized, and less invasive surgery without compromising oncological efficiency and safety. In this perspective, we have demonstrated the role of indocyanine green (ICG) and near-infrared (NIR) fluorescence imaging method in gastric cancer surgery. This technique may be used to improve localization of the tumor, detection of sentinel lymph nodes (SLN), real-time lymphatic mapping, and blood flow assessment (anastomosis perfusion).

Near-infrared-II ratiometric fluorescence probes for non-invasive detection and precise navigation surgery of metastatic sentinel lymph nodes.

Sentinel lymph node (SLN) biopsy is the key diagnostic procedure to determine tumor metastasis and treatment plan. Current SLN biopsy has considerable drawbacks in that SLNs (both malignant and normal) must be removed by navigation surgery, followed by a time-consuming pathological examination. The selective, non-invasive, and real-time diagnosis of metastatic status in SLNs is becoming essential.Methods: Here, we design two lanthanide-doped nanoparticles as a pair of NIR-II ratiometric fluorescence probes, one of which is conjugated with tumor-targeting moiety, while the other is conjugated with PEG as an internal reference. The NIR-II ratiometric fluorescence signal (I1060 nm/I1525 nm) from two well-separated channels were used to identify the tumor-draining SLNs. The precise navigation surgery of metastatic SLNs was performed and we further evaluated their surgery outcomes.Results: The NIR-II ratiometric fluorescence facilitates an ideal fluorescence-guided surgery with only resection of tumor-positive SLNs, thereby avoiding unnecessary removal of the normal SLNs. In addition, our system has a time-saving operation procedure and can be performed under the operation light without altering the appearance of surgical settings.Conclusion: The present study enables non-invasive and real-time detection metastatic status in SLNs with high sensitivity and selectivity. Our investigations will provide a new direction for SLN biopsy and substantially improve cancer surgery outcomes.

Sentinel lymph node localization and staging with a low-dose of superparamagnetic iron oxide (SPIO) enhanced MRI and magnetometer in patients with cutaneous melanoma of the extremity - The MAGMEN feasibility study

BackgroundIn patients with melanoma, sentinel lymph node (SLN) status is pivotal for treatment decisions. Current routine for SLN detection combines Technetium99m (Tc99) lymphoscintigraphy and blue dye (BD). The primary aim of this study was to examine the feasibility of using a low dose of superparamagnetic iron oxide (SPIO) injected intracutaneously to detect and identify the SLN, and the secondary aim was to investigate if a low dose of SPIO would enable a preoperative MRI-evaluation of SLN status. MethodsPatients with melanoma of the extremities were eligible. Before surgery, a baseline MRI of the nodal basin was followed by an injection of a low dose (0.02–0.5 mL) of SPIO and then a second MRI (SPIO-MRI). Tc99 and BD was used in parallel and all nodes with a superparamagnetic and/or radioactive signal were harvested and analyzed. ResultsFifteen patients were included and the SLNB procedure was successful in all patients (27 SLNs removed). All superparamagnetic SLNs were visualized by MRI corresponding to the same nodes on scintigraphy. Micrometastatic deposits were identified in four SLNs taken from three patients, and SPIO-MRI correctly predicted two of the metastases. There was an association between MRI artefacts in the lymph node and the dose SPIO given. DiscussionIt is feasible to detect SLN in patients with melanoma using a low dose of SPIO injected intracutaneously compared with the standard dual technique. A low dose of SPIO reduces the lymph node MRI artefacts, opening up for a non-invasive assessment of SLN status in patients with cancer.

Sentinel lymph node mapping in post chemotherapy nonseminoma testicular cancer patients undergoing retroperitoneal lymph node dissection: A series of nine cases.

Objective(s):Testicular germ cell cancers are the most common solid malignancy among young men at the age ranging between 14 and 35 years. In this study, we evaluated the feasibility of sentinel lymph node mapping using intraoperative injection of radiotracer in nonseminomatous testicular cancer patients with history of orchiectomy who were candidate for retroperitoneal lymph node dissection (RPLND) in post-chemotherapy setting.Methods:Nine consecutive cases were included in the study. Technetium-99m-labelled phytate was injected in two divided doses in the stump of the spermatic cord, through transabdominal approach. A hand-held gamma probe was used for radio-guided retroperitoneal sentinel lymph node detection intraoperatively and confirming the location of the sentinel lymph nodes.Results: Detection rate and the false negative rate were estimated as the main indices. The detection rate was 6/9 (66%) and the false negative rate was 0/2 (0%). Location of the dissected sentinel lymph nodes were interaortocaval (2 patients), internal iliac (1 patient), external iliac (1 patient), common iliac (2 patients), and paraaortic (1 patient).Conclusion:Sentinel lymph node mapping technique seems to be feasible and promising in post chemotherapy non-seminoma testis cancer patients who are candidate for RPLND; however, further larger studies are needed to increase and standardize the detection rate.

Drug Release from Gelsolin-Targeted Phase-Transition Nanoparticles Triggered by Low-Intensity Focused Ultrasound.

PurposeCurrent strategies for tumour-induced sentinel lymph node detection and metastasis therapy have limitations. It is essential to identify and provide warnings earlier for tumour metastasis to carry out effective clinical interventions. In addition, traditional cancer chemotherapy encounters drastic limitations due to the nonspecific delivery of antitumour drugs and severe side effects. We aimed to exploit the potential of gelsolin (GSN) monoclonal antibody as a targeting agent and perfluorohexane (PFH) as a phase-transition agent to maximize the cytotoxic effect of poly(lactic-co-glycolic acid) (PLGA) nanoparticle-based drug controllable release systems for Hca-F cells.MethodsWe co-encapsulated PFH and doxorubicin (DOX) into PLGA nanoparticles (NPs) and further conjugated GSN monoclonal antibody onto the surface of NPs to form GSN-targeted phase transition polymer NPs (GSN-PLGA-PFH-DOX) for both imaging and therapy of tumours and metastatic lymph nodes. To promote and trigger drug release on demand, low-intensity focused ultrasound (LIFU) was applied to achieve a controllable release of the encapsulated drug.ResultsGSN-PLGA-PFH-DOX NPs exhibited characteristics such as a narrow size distribution and smooth surface. GSN-PLGA-PFH-DOX NPs could also specifically bind to Hca-F cells and increase the ultrasound contrast agent (UCA) image contrast intensity. GSN-PLGA-PFH-DOX NPs enable GSN-mediated targeting and biotherapeutic effects as well as LIFU-responsive drug release, resulting in synergistic cytotoxic effects in GSN-overexpressing cells in vitro.ConclusionOur work might provide a strategy for the imaging and chemotherapy of primary tumours and their metastases.

Status of the Sentinel Lymph Node in Patients with Endometrial Cancer Stage I-II.

Endometrial cancer (EC) is the most common gynecological cancer in developed countries. In literature, there are discordant data regarding the therapeutic value of systematic lymphadenectomy whereas the importance of lymph node status for determining prognosis and the need for adjuvant treatment is undoubted. Given the low risk of lymph node metastases in stage I-II of EC and the significant surgical and postoperative risks when performing a complete pelvic lymphadenectomy, the surgical approach in these patients is controversial, ranging from no nodal evaluation to comprehensive pelvic and aortic lymphadenectomy. The recent introduction of sentinel node detection represents the mid-way between the execution and omission of node dissection in EC patients. Indeed, the sentinel node mapping has rapidly emerged as an alternative to complete lymphadenectomy to reduce morbidity. In the present research, we discuss the role of sentinel node mapping in the surgical management of EC in early stage. Results of study on SLN in EC in early stages seem to be promising, but only a small series have been published so far.

The added value of SLN mapping with indocyanine green in low- and intermediate-risk endometrial cancer management: a systematic review and meta-analysis

ObjectiveThe aim of this study was to assess the SLN detection rate in presumed early stage, low- and intermediate-risk endometrial cancers, the incidence of SLN metastases, and the negative predictive value of SLN mapping performed with indocyanine green (ICG).MethodsA systematic review with meta-analyses was conducted. Study inclusion criteria were A) low- and intermediate-risk endometrial cancer, B) the use of ICG per cervical injection; C) a minimum of twenty included patients per study. To assess the negative predictive value of SLN mapping, D) a subsequent lymphadenectomy was an additional inclusion criterion.ResultsFourteen studies were selected, involving 2,117 patients. The overall and bilateral SLN detection rates were 95.6% (95% confidence interval [CI]=92.4%–97.9%) and 76.5% (95% CI=68.1%–84.0%), respectively. The incidence of SLN metastases was 9.6% (95% CI=5.1%–15.2%) in patients with grade 1–2 endometrial cancer and 11.8% (95% CI=8.1%–16.1%) in patients with grade 1–3 endometrial cancer. The negative predictive value of SLN mapping was 100% (95% CI=98.8%–100%) in studies that included grade 1–2 endometrial cancer and 99.2% (95% CI=97.9%–99.9%) in studies that also included grade 3.ConclusionSLN mapping with ICG is feasible with a high detection rate and negative predictive value in low- and intermediate-risk endometrial cancers. Given the incidence of SLN metastases is approximately 10% in those patients, SLN mapping may lead to stage shifting with potential therapeutic consequences. Given the high negative predictive value with SLN mapping, routine lymphadenectomy should be omitted in low- and intermediate-risk endometrial cancer.

Advantages of Sentinel Lymph Node Mapping by Single Photon Emission Computed Tomography/Computed Tomography in Early-Stage Malignant Head-and-Neck Skin Tumors.

Background:The aim of this study was to determine the advantages of preoperative sentinel lymph node mapping (SLNM) by single photon emission computed tomography/computed tomography (SPECT / CT) in patients with early-stage cutaneous head-and-neck malignancies.Materials and Methods:We conduct a 7-year and 6 months retrospective, cross-sectional study. Patients with early-stage malignant head-and-neck skin tumors and cutaneous adnexa who underwent SLNM by SPECT/CT from March 2012 and December 2019, were included in the study.Results:We retrospectively analyzed 28 patients: Melanoma was the most frequent tumor (64.2%), followed by squamous cell carcinoma (25%). The anterior cheek was the most common functional subsite (25%). Twenty-seven patients (96.4%) had a successful SLN detection with SPECT/CT. Neck lymph node dissection was performed in 23 patients (82.1%). According to the pathological specimen, lymph nodes were found in all of them; hence, the efficacy of the SPECT/CT for SLNM was 100%. At 7-year follow-up, systemic recurrence was found in one patient (3.6%), another had locoregional recurrence (3.6%), and the mortality rate was 3.6%.Conclusions:In early-stage malignant head-and-neck skin tumors, there is a high concordance between SLN found by SPECT/CT and the histopathological results. Preoperative SPECT/CT accurately detects the SLN, assesses unexpected lymph nodes and their drainage pathways, and facilitates their location by reliably showing the relationships between sentinel nodes and important anatomic structures. This allows to perform a clear preoperative evaluation, an accurate staging for all patients and to avoid excessive dissections that could result in cosmetic and functional deformities.

Management of the axilla: Conventional tracers vs ICG-fluorescence in sentinel lymph node biopsy

The evaluation of regional lymph nodes is part of breast cancer staging. Biopsy of the sentinel lymph node was established, in order to evaluate the condition of the axillary lymph nodes without having to complete an axillary dissection. The concept of sentinel lymph node (SLN) is based on the theory of sequential dissemination of tumor cells through the lymph. When lymphatic dissemination occurs, the invasion initially occurs in the first lymph node that drains lymph from the tumor. This lymph node has been named GS and depending on its negative or positive status, the presence or absence of metastases in the remaining regional lymph nodes can be established. Blue dye (BD) and radioactive isotopes (RI) are routinely used markers for identification of the sentinel lymph nodes during sentinel lymph node biopsy (SLNB) in early stage breast cancer. Unlike the blue dye technique, using radioactive isotopes has lower false-negative rates. Nonetheless, the need of lymphoscintigraphy, the time needed for preoperative injection, and undetected sentinel lymph nodes in some cases cause surgeons to rely only on the combination of blue dye and radioisotopes. At present, indocyanine green (ICG) fluorescence method (ICG-SLNB) is starting to gain more and more field as an alternative to conventional mapping methods. The purpose of this review is to compare ICG with the conventional methods (blue dye and radioactive isotopes) and their role in detection of SLN.

Utility of indocyanine green in the administration of cytotoxic drugs in breast cancer patients

Indocyanine green has been widely introduced in breast cancer protocol for sentinel node detection, for upper limb lymphedema prevention and for breast reconstruction. However, more recent studies came to demonstrate that these particles can be also used in order to provide an efficient intraoperative detection of metastatic deposits as well as for a more targeted delivery of cytotoxic drugs. The current paper aims to investigate the mechanisms of action, the principles and the benefits of indocyanine green as a therapeutic tool, part of the medical oncologic treatment of breast cancer patients.

Within-patient comparison between [68Ga]Ga-tilmanocept PET/CT lymphoscintigraphy and [99mTc]Tc-tilmanocept lymphoscintigraphy for sentinel lymph node detection in oral cancer: a pilot study

To compare sentinel lymph node (SLN) identification using [68Ga]Ga-tilmanocept PET/CT lymphoscintigraphy to [99mTc]Tc-tilmanocept lymphoscintigraphy (including SPECT/CT) in early-stage oral cancer. Furthermore, to assess whether reliable intraoperative SLN localization can be performed with a conventional portable gamma-probe using [99mTc]Tc-tilmanocept without the interference of [68Ga]Ga-tilmanocept in these patients. This prospective within-patient comparison pilot study evaluated SLN identification by [68Ga]Ga-tilmanocept PET/CT lymphoscintigraphy compared to conventional lymphoscintigraphy using [99mTc]Tc-tilmanocept (~ 74MBq) in 10 early-stage oral cancer patients scheduled for SLN biopsy. After conventional [99mTc]Tc-tilmanocept lymphoscintigraphy, patients underwent peritumoral administration of [68Ga]Ga-tilmanocept (~ 10MBq) followed by PET/CT acquisition initiated 15min after injection. Intraoperative SLN localization was performed under conventional portable gamma-probe guidance the next day; the location of harvested SLNs was correlated to both lymphoscintigraphic images in each patient. A total of 24 SLNs were identified by [99mTc]Tc-tilmanocept lymphoscintigraphy, all except one were also identified by [68Ga]Ga-tilmanocept PET/CT lymphoscintigraphy. [68Ga]Ga-tilmanocept PET/CT lymphoscintigraphy identified 4 additional SLNs near the injection site, of which two harbored metastases. Lymphatic vessels transporting [68Ga]Ga-tilmanocept were identified by PET/CT lymphoscintigraphy in 80% of patients, while draining lymphatic vessels were visualized by [99mTc]Tc-tilmanocept lymphoscintigraphy in 20% of patients. Of the 33 SLNs identified by [68Ga]Ga-tilmanocept PET/CT lymphoscintigraphy, 30 (91%) were intraoperatively localized under conventional gamma-probe guidance. [68Ga]Ga-tilmanocept PET/CT lymphoscintigraphy provided more accurate identification of SLNs and improved visualization of lymphatic vessels compared to [99mTc]Tc-tilmanocept lymphoscintigraphy. When combined with peritumoral administration of [99mTc]Tc-tilmanocept, SLNs detected by [68Ga]Ga-tilmanocept PET/CT lymphoscintigraphy can be reliably localized during surgery under conventional gamma-probe guidance.

Assessment of sentinel lymph node detection by radioisotope scan and methylene blue alone in operable oral cavity cancer to assess its accuracy for metastasis

Background: Squamous cell carcinoma (SCC) is the most common malignancy affecting the oral cavity. It typically metastasizes into the regional cervical lymph nodes before spreading to distant organs.Methods: A prospective study on sentinel lymph node biopsy (SLNB) in early oral cancers using methylene blue dye and sentinel node localisation using pre-operative lymphoscintigraphy and intraoperative gamma probe in early oral cavity cancer.Results: Present study had a male to female ratio of 1.9:1, with (65.5%) male and (34.5%) female patients. Present study had a side distribution of disease more on left side with 138 patients (62.7%) and ratio of left to right was approximately 1.7:1. In present study most predominating gross morphological pattern of growth was ulcerative (35%) followed by ulcero-infilterative (25%). Buccal mucosa was the most common sub-site of origin of carcinoma in oral cavity, followed by tongue, with 83 (37.7%) and 64 (29.1%) patients. Identification rate of methylene blue dye was 91.7% (100 out of 109 patient). Identification rate of radionuclide tracer was 94.6% (105 out of 111 patient). In methylene blue dye group out of 103 metastatic sentinel lymph nodes, 9 metastatic sentinel lymph nodes were detected on IHC.Conclusions: With the above results it can be concluded the SLNB study is liable in detection of actual positive node and can avoid unnecessary neck dissections in patients with SCC with negative sentinel lymph node, as having very low risk of occult lymphatic metastases in the remaining lymphatic drainage.

Fluorescent sentinel lymph node mapping with icg in endometrial cancer. An initial experience in Argentina

Background: Near-infrared fluorescence-based sentinel lymph node (SLN) mapping technique with indocyanine green (ICG) has been found a useful surgical modality for sentinel node detection and disease staging in endometrial cancer (EC) worldwide. Objective: We aimed to introduce the SNL mapping technology using ICG and Near Infrared (NIR) fluorescence in Argentina. We aimed to assess the overall and bilateral detection rate of ICG based SNL mapping along with verifying its feasibility and effectiveness in surgical staging. We also aimed to discover the perceptions of surgeons regarding the use of ICG as a tracer and NIR as light-medium in SNL mapping. Method: ICG SLNs identification was evaluated retrospectively. This study was performed at the Hospital Aleman de Buenos Aires in September, 2017The detection rates were calculated along with the analysis of the number of SNL observed and operative time, and time taken by overall surgery. Subsequently, the surgeons were interviewed to ascertain their opinion of using ICG SNL mapping in endometrial cancer staging. Results: Four patients with endometrial cancer were included for analysis. The overall and bilateral detection rates have been 100% and 75%, respectively. While, under white light, no SLNs were identified. The average operative time of nodes resection was estimated 2.15 minutes. The fluorescence has been used for 2.2 minutes and overall time taken by surgery was estimated 71.5 minutes. The estimated blood loss (EBL) has been lower than 50 ml. The responses of surgeons’ from the interview have been 100% positive. The cost of the procedure based on the amount of dye used was 25 dollars per patient. Conclusion: Laparoscopic ICG SLN resulted to be feasible, practical and no expensive surgical modality for uterine cancer triage.

Role of sentinel lymph node biopsy for gynecologic cancers.

To provide an overview of the current knowledge and recent advances of sentinel lymph node (SLN) assessment in uterine, cervical, vulvar, and ovarian cancers. In endometrial cancer, SLN evaluation has become increasingly utilized as part of the treatment of early-stage disease, with data showing improved detection of pelvic lymph node metastasis. In cervical cancer, SLN biopsy has also gained increasing traction with studies demonstrating the feasibility and accuracy of SLN detection. Evaluation with frozen section, however, remains limited in the detection of metastases. The prognostic significance of positive SLN in vulvar cancer is currently being investigated, with preliminary data showing lower recurrence rates in patients receiving adjuvant radiation. SLN evaluation remains standard of care to detect lymph node metastasis in early-staged endometrial cancer. In cervical cancer, SLN biopsy has been shown to be reliable, while decreasing morbidity without impacting disease-free survival in select patients. The technique and high sensitivity of SLN biopsy in vulvar cancer has been demonstrated in large prospective trials. There are no randomized controlled trials in ovarian cancer that evaluate the role of SLN biopsy on treatment and outcome; current SLN evaluation remains investigational.

The place of lymph dissection in the treatment of cancer and the choice of surgical tactics (review article)

Over the past years, due to increase of detection of patients with early-stage stomach cancer and colorectal cancer, and improvement of survival rate, the efforts have been made to gradually develop the concept of sentinel lymph nodes detection in order to improve postoperative quality of life. The article presents the review of the literature on the feasibility of sentinel lymph nodes intraoperative diagnosis the choice of surgical treatment of patients with tumors of the stomach and colon. Analytical work demonstrates that the real time intraoperative visualization of lymph sineses using fluorescent imaging of indocyanine green during laparoscopic surgery for stomach or colorectal cancer is possible and it is a useful method of the lymph nodes mapping, therefore it can lead to intraoperative changes at lymphadenectomy as well as to reduce the surgical injury. It indicates the need in further research and improvement of approach.

Preoperative Axillary Ultrasound-guided Wire Localization and Lymphoscintigraphy for Sentinel Lymph Node Biopsy in Breast Cancer Patients

Background: Breast cancer has the highest incidence and mortality among female malignant tumors. Breast cancer with negative axillary lymph nodes has been diag- nosed mainly at an early stage. Sentinel lymph node biopsy (SLNB) is a standard screening technique for patients with early-stage breast cancer and clinically nega- tive lymph nodes. Lymphoscintigraphy (sentinel lymph node mapping) has been reg- ularly used as the standard method for SLNB. Today, ultrasound-guided wire locali- zation (USGWL) is a well-established technique with superior outcomes. Therefore, we attempted to determine whether preoperative UGWL and lymphoscintigraphy (blue dye and isotope injection) improve SLN detection and false-negative rate in breast cancer patients undergoing SLNB and identify clinical factors that may affect the diagnostic accuracy of axillary ultrasound (AUS). Methods: Between December 2018 and June 2019, 55 patients with clinical T1- 3N0 breast cancer eligible for an SLNB at Imam Khomeini Hospital in Tehran were included in our study. Tumor characteristics and demographic data were collect- ed by reviewing medical records and questionnaires prepared by our surgical team. The day before SLNB, all patients underwent ultrasound-guided wire localization of SLN. Lymphoscintigraphy was performed with an unfiltered 99mTc-labelled sulfur colloid peritumoral injection followed by methylene blue dye injection. The results were analyzed based on the permanent pathology report. Results: Among the 55 patients, 71.8% of SLNs were detected by wire localization, while 57.8% were found by methylene blue mapping and 59.6% by gamma probe detection. Compared with wire localization and isotope injection, the methylene blue dye technique had a low sensitivity (72.2%), while both wire localization and isotope injection reached 77.8%. The sensitivity, specificity, and accuracy of UGWL were 77.8%, 42.1%, and 65.4%, respectively. Otherwise, methylene blue dye and isotope injection accuracy was 47.3% and 50.1%, respectively. Furthermore, there was a significant relationship between BMI, tumor size, laterality, reactive ALN, and the accuracy of preoperative AUS. But there was no significant correlation between age, weight, height, tumor biopsy, tumor location, the time interval between methylene blue dye and isotope injection to surgery, and also the type of surgery to the accuracy of preoperative AUS. Conclusion: Preoperative UGWL can effectively identify SLNs compared to lym- phoscintigraphy (blue dye and isotope injection) in early breast cancer patients un- dergoing SLNB.

Detection of the sentinel lymph node with hybrid tracer (ICG-[99mTc]Tc-albumin nanocolloid) in intermediate- and high-risk endometrial cancer: a feasibility study

PurposeIndocyanine green (ICG) is frequently used for the detection of the sentinel lymph node (SLN) in gynecology, but it carries the loss of the presurgical SLN mapping provided by [99mTc]-based colloids. Hybrid tracers such as ICG-[99mTc]Tc-albumin nanocolloid combine the benefits of both components. The aim of this study was to evaluate the feasibility and applicability of this hybrid tracer injected by transvaginal ultrasound-guided myometrial injection of radiotracer (TUMIR) approach in the detection of SLNs in patients with intermediate- and high-risk EC.MethodsFifty-two patients with intermediate- and high-risk EC underwent SLN biopsy after injection of a hybrid tracer using the TUMIR approach, followed by pelvic and paraaortic lymphadenectomy. SLNs were detected preoperatively by lymphoscintigraphic study and intraoperatively by gamma probe and near-infrared (NIR) optical laparoscopic camera.ResultsPreoperative lymphatic drainage was obtained in 69% and intraoperative detection in 71.4% of patients. A total of 146 SLNs (4.17 SLNs/patient) were biopsied. Pelvic bilateral detection was observed in 57% of the women and paraaortic drainage in 34% of the patients. The radioactive component allowed the detection of SLN in 97.1% of the patients, while the fluorescent component detected 80%. In more than 17% of the patients with intraoperative detection, SLNs were detected only by the radioactive signal. Lymph node metastasis was identified in 14.3% of patients submitted to SLNB. The sensitivity and negative predictive value for metastatic involvement were 100%.ConclusionTUMIR injection of a hybrid tracer in patients with intermediate- and high-risk EC combines the benefits of the radiotracer and the fluorescence methods with a single tracer. The method increases the paraaortic detection rate and allows a potential increase in SLN detection. Notwithstanding, based on our findings, the radioactive component of the hybrid tracer cannot be obviated.

Rationale for extent of operation choice in rectal cancer

Introduction. Colorectal cancer (CRC) remains relevant occupying one of the leading places in morbidity and mortality among oncological diseases. It reaches 13.5% in the structure of tumor diseases tending to increase.
 The aim of the work to improve the choice of surgical treatment management and reduce the number of intraoperative and postoperative complications in rectal cancer patients.
 Materials and methods. 184 operated patients with rectal cancer (RC) were divided into 2 groups: 1 group (patients with stage I RC (T1-2N0M0) and 2 group (stage II RC (T3N0M0)) who were carried out intraoperative detection and examination of sentinel lymph nodes. The volume and surgical approach depended on the stage and the presence of metastases (MTS). The average period of postoperative observation was 12–60 months, taking into account early (purulent-septic complications, bleeding, intestinal perforation) and distant (recurrence of rectal cancer) complications.
 Results. The patients of the 1 group had no MTS lesions of sentinel lymph nodes, due to this fact the surgical intervention was limited to transanal microsurgery. Among the complications were the following: bleeding – 2.2%; intraoperative perforation of the intestinal wall – 5.6%. No purulent-septic cases, no recurrences of rectal cancer were detected. In group 2, of 94 patients, 36 (38.3%) had MTS detected intraoperatively in sentinel lymph nodes which required a low anterior rectal resection with total mesorectomectomy. Among the complications was bleeding – 6.3%. No intraoperative perforations of the intestinal wall and no purulent-septic complications were detected. Recurrence of rectal cancer was detected in 12 (13.8%) patients.
 Conclusions. Performing transanal endoscopic resections in patients with RC I and especially stage II is possible only under the conditions of mandatory intraoperative staining and emergency histological examination of "sentinel" lymph nodes. The extent of surgical intervention is determined on the operating table based on the results of an emergency histological examination. When MTS lesions of the mesorectal "sentinel lymph nodes" are detected, the operation should be continued with mandatory mesorectomectomy.

Role of methylene blue in detecting the sentinel lymph node in colorectal cancer: In vivo vs. ex vivo technique.

The identification of sentinel lymph nodes is a valuable oncological method, which aims at mapping lymphatic drainage and has the advantage of correctly staging the disease and assessing prognosis. Lymph node invasion is an important prognostic feature. In colorectal cancer, lymphadenectomy is not influenced by the positive or negative status of the sentinel lymph node. The identification of lymph nodes with possible invasion by staining the primary tumor with methylene blue can lead to improved staging and management. In other words, the consequent administration of neoadjuvant therapy (chemotherapy) to the appropriate patients may result in lower recurrence rates. Thus, the aim of the present study was to use methylene blue to identify the sentinel node/nodes in colorectal cancer and to determine whether the dye-capturing nodes were invaded by the tumor. This is a non-randomized prospective study, in which 26 patients with colon cancer with surgical indication were enrolled. Two types of methods were utilized: in vivo (16 patients) and ex vivo (10 patients). The identification rate was 75% for the in vivo technique and 60% for the ex vivo technique, resulting in a 69.26% overall identification rate. Of 18 patients with sentinel lymph nodes identified using dye, routine histological examination detected metastases in 6 (33.33%) of these patients. In conclusion, further research should be conducted into how the clinical application of sentinel node detection can be employed in colorectal cancer.

Challenging Visualization of Sentinel Lymph Nodes in Upper Urinary Tract Urothelial Carcinoma.

Purpose: The purpose of this study was to assess the possibility of detecting sentinel lymph nodes (SLNs) and to perform analysis of lymphatic outflow in patients with suspicion of upper tract urothelial carcinoma (UTUC) with the use of a radioisotope-based technique. Methods: During 2018–2021, a prospective study was conducted on 19 patients with the suspicion of UTUC and for whom diagnostic ureterorenoscopy (URS) was planned. Technetium-99m (99mTc) nanocolloid radioactive tracer injection and a tumor biopsy were performed for staging procedures. Three-dimensional (3D) reconstruction and fusion of images were performed for better localization of lymph nodes (LNs). Detection of SLNs and the analysis of the radiotracer outflow was conducted with the use of single-photon emission-computed tomography/computed tomography (SPECT/CT) lymphangiography. Results: The mean age of the patients was 73.4 years; 7 (36%) were male. Pathological staging from the biopsy was T0—8 (42%), Ta—7 (36%), T1—4 (21%). SLNs were detected in two of 19 cases (10%). In one patient a single SLN (5.3%) was visualized, and in another case (5.3%), multiple (double) radioactive lymph nodes were visualized. In 17 out of the 19 (89.5%) cases, no lymphatic outflow was observed, and out of these five cases (26.3%) of gravitational leakage of injected radiotracer to the retroperitoneal space was noted. Conclusions: We demonstrated that detection of SLNs in the upper urinary tract is possible yet challenging. Radiotracer injection in the upper urinary tract during ureterorenoscopy is difficult to perform, and the expected result of injection is unsatisfactory. Lymphatic outflow from the tumor site to the first LNs in our studied group of patients is visible in 10.5% of cases. SPECT/CT lymphangiography in cases of UTUC may provide valuable information about a patient’s individual anatomy of the lymphatic system and the position of the first lymph nodes draining lymph with potential metastatic cells from the tumor.