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

Purpose Indocyanine 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. Methods Fifty-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. Results Preoperative 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%. Conclusion TUMIR 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.

Lymphadenectomy for oncogynecological pathology: evaluation of lymph cyst formation and detection of metastases depending on the number of lymph nodes removed

Introduction. Lymphadenectomy in gynecological oncology allows performing adequate surgical staging, determining the need for adjuvant therapy, and reducing the risk of disease recurrence. An increase in the volume of lymphadenectomy leads to an increase in the incidence of postoperative complications — the formation of lymphatic cysts. There are no clear recommendations on the required number of removed lymph nodes in order to identify their metastatic lesions. The aim of the study was to study the possible dependence of the number of removed lymph nodes and the formation of lymphatic cysts. Materials and methods. A retrospective study of 219 patients after surgical treatment from 2020 to 2021 was carried out on the basis of GBUZ Chelyabinsk Regional Center of Oncology and Nuclear Medicine. The study included cases of stage I-IV uterine cancer of all histological types, which underwent radical hysterectomy with bilateral pelvic or bilateral pelvic and paraaortic lymphadenectomy; cases of cervical cancer stage IA1-IIA disease after radical hysterectomy II-III type according to the classification of M.S. Piver, F. Rutledge (1974) with performing bilateral pelvic lymphadectomy. Statistical processing of the results was carried out. Results. The percentage of complications (lymphatic cysts) in the cervical cancer group was 2.06% (N = 2), in the uterine body cancer group 1.72 (N = 2). There was no statistically significant relationship between the removed lymph nodes and their metastatic lesions. Removing more than 27 lymph nodes is a risk factor for developing lymphatic cysts. Discussion. Lymphadenectomy allows for adequate surgical staging and reduces the risk of disease recurrence. Complicated lymphatic cysts occur in 0.9-34% of cases, which was reflected in our study, but the percentage of these complications is quite low. Conclusion. The increase in the volume of lymphadenectomy (removal of more lymph nodes) is justified by the desire for accuracy in the surgical staging of the tumor process. Despite this, there is a risk of complications after lymphadenectomy — the formation of lymphatic cysts that occurs when 27 or more lymph nodes are removed.

Recurrence of rare malignant Brenner ovarian tumor

Summary: Objective: Description of the case of recurrence of a rare malignant Brenner ovarian tumour. Methods: Author observation and literature resources. Results: Occurrence of a rare malignant Brenner's tumor in a 66-year-old patient. After radical surgery (abdominal hysterectomy with bilateral adnexectomy, pelvic and paraaortic lymphadenectomy, omentectomy and appendectomy) and after adjuvant chemotherapy, recurrence of the disease was observed after 30 months. Conclusions: The case report describes rare occurrence of a malignant Brenner tumour and its relapse.

Detection of the Sentinel Lymph Node With Hybrid Tracer (ICG-[99mTc]Tc-albumin Nanocolloid) in Intermediate and High Risk Endometrial Cancer. A Feasibility Study

Purpose: Indocyanine 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. Methods: Fifty-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. Results: Preoperative 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 were identified in 14.3% of patients submitted to SLNB. The sensitivity and negative predictive value for metastatic involvement were 100%. Conclusion: TUMIR 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.

O69: THE SENTINEL LYMPH NODE TECHNIQUE IN THE ENDOMETRIAL CANCER

Introduction The sentinel lymph node (SLN) concept represents advancement in the management of the endometrial cancer (EC). We aim to assess the performance of the SLN procedure; its positive predictive value (PPV) and negative predictive value (NPV); in stage I of EC (FIGO2009). Method A prospective study is conducted in our institution. We perform a double detection of the SLN (radiolabel Tc 99 microsulfur colloid and a color method using patent blue) followed by pelvic lymphadenectomy with or without paraaortic lymphadenectomy. A pelvic MRI is performed to determine myometrial invasion and nodal status. The injection of Tc 99m colloid occurs the day prior to surgery. The injection into the stroma of the cervix at the 3 and 9 o'clock positions was performed by an oncologist surgeon with the assistance of a nuclear medicine physician. Preoperative lymphoscintigraphy was obtained after 90-120 minutes. We inject into the cervical stroma 2cc of patent blue similar to the Tc99 injection. A gamma detecting probe is used to locate radioactive lymph nodes. The SLNs identified then are labelled as radioactive and/or blue. No frozen-section analysis was performed. Results For the pathological analysis of the SLN, Haematoxylin Eosin is used. If there is no metastasis detected, an ultra staging protocol using different anti-cytokeratines is conducted. Studies have shown that this approach is possible having satisfactory results when conducted by dedicated surgical, radiology and pathology team. We look forward to our outcomes to illustrate those results. Take-home message Sentinel lymph node is a good alternative for gynecological cancer