Integration of Hybrid Single-Photon Emission Computed Tomography/Computed Tomography in the Preoperative Assessment of Sentinel Node in Patients With Cervical and Endometrial Cancer: Our Experience and Literature Review

Molecular image-guided surgery in gynaecological cancer: where do we stand?

PURPOSE

The aim of this review is to give an overview of the current status of molecular image-guided surgery in gynaecological malignancies, from both clinical and technological points of view.

METHODS

A narrative approach was taken to describe the relevant literature, focusing on clinical applications of molecular image-guided surgery in gynaecology, preoperative imaging as surgical roadmap, and intraoperative devices.

RESULTS

The most common clinical application in gynaecology is sentinel node biopsy (SNB). Other promising approaches are receptor-target modalities and occult lesion localisation. Preoperative SPECT/CT and PET/CT permit a roadmap for adequate surgical planning. Intraoperative detection modalities span from 1D probes to 2D portable cameras and 3D freehand imaging.

CONCLUSION

After successful application of radio-guided SNB and SPECT, innovation is leaning towards hybrid modalities, such as hybrid tracer and fusion of imaging approaches including SPECT/CT and PET/CT. Robotic surgery, as well as augmented reality and virtual reality techniques, is leading to application of these innovative technologies to the clinical setting, guiding surgeons towards a precise, personalised, and minimally invasive approach.

Validation of single-photon emission computed tomography with computed tomography and lymphoscintigraphy for sentinel lymph node identification in cervical cancer

OBJECTIVE

To compare single-photon emission computed tomography with computed tomography (SPECT/CT) and lymphoscintigraphy (LSG) for the detection of sentinel lymph nodes (SLNs) in patients with early-stage cervical cancer.

METHODS

This hospital-based, single-center, retrospective study included 128 patients with cervical cancer (aged >18 years) treated between 2014 and 2022. Injection of 99 m Technetium-labeled phytate into the uterine cervix was used to detect pelvic SLNs. SNL identification rates and locations were analyzed for preoperative LSG and SPECT/CT.

RESULTS

Median age and body mass index of patients were 40 years (range, 20-78 years) and 21.7 kg/m2 (range, 16-40 kg/m2 ), respectively. There was no significant difference in overall identification rates (identification of at least one SLN) of SLNs between SPECT/CT (91%) and LSG (88%). There was no significant difference in bilateral SLN identification rates between SPECT/CT (66%) and LSG (65%). A total of 219 pelvic SLNs (110 right and 109 left hemipelvis) were identified by SPECT/CT; the most frequent locations were the obturator (122 SLNs, 56%) and external iliac (67 SLNs, 30%).

CONCLUSION

SPECT/CT and LSG showed high SLN identification rates in patients with cervical cancer, and there was no significant difference in overall or bilateral SLN identification rates between the two techniques.

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.

Sentinel node biopsy for diagnosis of lymph node involvement in endometrial cancer

BACKGROUND

Pelvic lymphadenectomy provides prognostic information for those diagnosed with endometrial (womb) cancer and provides information that may influence decisions regarding adjuvant treatment. However, studies have not shown a therapeutic benefit, and lymphadenectomy causes significant morbidity. The technique of sentinel lymph node biopsy (SLNB), allows the first draining node from a cancer to be identified and examined histologically for involvement with cancer cells. SLNB is commonly used in other cancers, including breast and vulval cancer. Different tracers, including colloid labelled with radioactive technetium-99, blue dyes, e.g. patent or methylene blue, and near infra-red fluorescent dyes, e.g. indocyanine green (ICG), have been used singly or in combination for detection of sentinel lymph nodes (SLN).

OBJECTIVES

To assess the diagnostic accuracy of sentinel lymph node biopsy (SLNB) in the identification of pelvic lymph node involvement in women with endometrial cancer, presumed to be at an early stage prior to surgery, including consideration of the detection rate.

SEARCH METHODS

We searched MEDLINE (1946 to July 2019), Embase (1974 to July 2019) and the relevant Cochrane trial registers.

SELECTION CRITERIA

We included studies that evaluated the diagnostic accuracy of tracers for SLN assessment (involving the identification of a SLN plus histological examination) against a reference standard of histological examination of removed pelvic +/- para-aortic lymph nodes following systematic pelvic +/- para-aortic lymphadenectomy (PLND/PPALND) in women with endometrial cancer, where there were sufficient data for the construction of two-by-two tables.

DATA COLLECTION AND ANALYSIS

Two review authors (a combination of HN, JM, NW, RG, and WH) independently screened titles and abstracts for relevance, classified studies for inclusion/exclusion and extracted data. We assessed the methodological quality of studies using the QUADAS-2 tool. We calculated the detection rate as the arithmetic mean of the total number of SLNs detected out of the total number of women included in the included studies with the woman as the unit of analysis, used univariate meta-analytical methods to estimate pooled sensitivity estimates, and summarised the results using GRADE.

MAIN RESULTS

The search revealed 6259 unique records after removal of duplicates. After screening 232 studies in full text, we found 73 potentially includable records (for 52 studies), although we were only able to extract 2x2 table data for 33 studies, including 2237 women (46 records) for inclusion in the review, despite writing to trial authors for additional information. We found 11 studies that analysed results for blue dye alone, four studies for technetium-99m alone, 12 studies that used a combination of blue dye and technetium-99m, nine studies that used indocyanine green (ICG) and near infra-red immunofluorescence, and one study that used a combination of ICG and technetium-99m. Overall, the methodological reporting in most of the studies was poor, which resulted in a very large proportion of 'unclear risk of bias' ratings. Overall, the mean SLN detection rate was 86.9% (95% CI 82.9% to 90.8%; 2237 women; 33 studies; moderate-certainty evidence). In studies that reported bilateral detection the mean rate was 65.4% (95% CI 57.8% to 73.0%) . When considered according to which tracer was used, the SLN detection rate ranged from 77.8% (95% CI 70.0% to 85.6%) for blue dye alone (559 women; 11 studies; low-certainty evidence) to 100% for ICG and technetium-99m (32 women; 1 study; very low-certainty evidence). The rates of positive lymph nodes ranged from 5.2% to 34.4% with a mean of 20.1% (95% CI 17.7% to 22.3%). The pooled sensitivity of SLNB was 91.8% (95% CI 86.5% to 95.1%; total 2237 women, of whom 409 had SLN involvement; moderate-certainty evidence). The sensitivity for of SLNB for the different tracers were: blue dye alone 95.2% (95% CI 77.2% to 99.2%; 559 women; 11 studies; low-certainty evidence); Technetium-99m alone 90.5% (95% CI 67.7% to 97.7%; 257 women; 4 studies; low-certainty evidence); technetium-99m and blue dye 91.9% (95% CI 74.4% to 97.8%; 548 women; 12 studies; low-certainty evidence); ICG alone 92.5% (95% CI 81.8% to 97.1%; 953 women; 9 studies; moderate-certainty evidence); ICG and blue dye 90.5% (95% CI 63.2.6% to 98.1%; 215 women; 2 studies; low-certainty evidence); and ICG and technetium-99m 100% (95% CI 63% to 100%; 32 women; 1 study; very low-certainty evidence). Meta-regression analyses found that the sensitivities did not differ between the different tracers used, between studies with a majority of women with FIGO stage 1A versus 1B or above; between studies assessing the pelvic lymph node basin alone versus the pelvic and para-aortic lymph node basin; or between studies that used subserosal alone versus subserosal and cervical injection. It should be noted that a false-positive result cannot occur, as the histological examination of the SLN is unchanged by the results from any additional nodes removed at systematic lymphadenectomy.

AUTHORS' CONCLUSIONS

The diagnostic test accuracy for SLNB using either ICG alone or a combination of a dye (blue or ICG) and technetium-99m is probably good, with high sensitivity, where a SLN could be detected. Detection rates with ICG or a combination of dye (ICG or blue) and technetium-99m may be higher. The value of a SLNB approach in a treatment pathway, over adjuvant treatment decisions based on uterine factors and molecular profiling, requires examination in a high-quality intervention study.

Low-Volume Nodal Metastasis in Endometrial Cancer: Risk Factors and Prognostic Significance

Objective: To evaluate the oncological outcomes of patients with low-volume metastasis compared to those with macrometastasis and negative nodes in endometrial cancer. Methods: A single institutional retrospective study was carried out, which included all patients with endometrial cancer who underwent surgical treatment between January 2007 and December 2016. We analyzed the progression-free survival (PFS) and overall survival (OS) of all patients after sentinel node biopsy and full nodal surgical staging according to their final pathological nodal status, focusing on the impact of the size of nodal metastasis. Results: A total of 270 patients were operated on during the study period; among them, 230 (85.2%) patients underwent nodal staging. On final pathology, 196 (85.2%) patients had negative lymph nodes; low-volume metastasis (LVM) was present in 14 (6.1%) patients: 6 (2.6%) patients had isolated tumor cells (ITCs) and 8 (3.5%) patients presented just micrometastasis; additionally, 20 (8.7%) patients presented macrometastasis. After a median (range) follow-up of 60 (0-146) months, patients with macrometastasis showed a significantly worse PFS compared to LVM and node-negative patients (61.1% vs. 71.4% vs. 83.2%, respectively; p = 0.018), and similar results were obtained for 5-year OS (50% vs. 78.6% vs. 81.5%, respectively; p < 0.001). Half of the patients presenting LVM did not receive adjuvant treatment. Moreover, LVM had a moderate nonsignificant decrease in 5-year PFS compared to node-negative patients. Conclusions: Patients with endometrial cancer and low-volume nodal metastasis demonstrated a better prognosis than those presenting macrometastasis. Low-volume metastasis did not show worse oncological outcomes than node-negative patients, although there was a slight decrease in progression-free survival.

Comparison of lymphoscintigraphy and single photon emission computed tomography with computed tomography (SPECT/CT) for sentinel lymph node detection in endometrial cancer

BACKGROUND

Endometrial cancer is the most common gynecologic cancer, and lymph node metastasis is one of the most important prognostic factors. Increasing evidence shows that sentinel lymph node (SLN) mapping is an effective alternative to comprehensive lymphadenectomy. Single photon emission CT with computed tomography (SPECT/CT) is associated with a high SLN detection rate.

OBJECTIVE

To compare the clinical efficacy of SPECT/CT with that of lymphoscintigraphy in detecting SLNs in patients with endometrial cancer.

METHODS

Between May 2014 and October 2018, 151 patients with endometrial cancer were enrolled in this study at the Department of Obstetrics and Gynecology of the Kagoshima University Hospital. Inclusion criteria were patients with endometrial cancer, older than 18 years, and with pre-operative International Federation of Gynecology and Obstetrics (FIGO) staging of I and II. All patients underwent pre-operative CT, and patients with suspected peritoneal dissemination and lymph node metastasis were excluded from this study. Pelvic SLNs were detected by injection of tecnetium-99m-labeled phytate into the uterine cervix. The number and locations of SLNs detected using lymphoscintigraphy and SPECT/CT were evaluated. JMP software (version 14, SAS Institute Inc., Cary, North Carolina, USA) was used for statistical analysis.

RESULTS

A total of 151 patients who underwent pre-operative lymphoscintigraphy and SPECT/CT were included in the study. The median age was 57 years (range 24-79), and the median body mass index was 24.3 kg/m2 (range 16-40). The final pathology was as follows: 135 (89%) endometrioid carcinoma, 11 (7%) serous carcinoma, one (1%) clear cell carcinoma, and four (3%) other histotypes. Based on SPECT/CT, 204 pelvic SLNs were detected. The bilateral pelvic SLN detection rate was better for SPECT/CT (43% (65/151)) than for lymphoscintigraphy (32% (48/151)) (p<0.0001). The overall pelvic SLN detection rate (at least one pelvic SLN detected) was also better with SPECT/CT (77% (16/151)) vs lymphoscintigraphy (68% (102/151)) (p<0.0001). The distribution of SLN locations detected using SPECT/CT was as follows: external iliac, 91 (45%); obturator, 61 (30%); common iliac, 28 (14%); internal iliac, 19 (9%); para-aortic, 2 (1%); parametrium, 2 (1%), and presacral, 1 (1%). The SLN detection rate using SPECT/CT was significantly worse in patients of advanced age (p<0.0001).

DISCUSSION

Overall and bilateral SLN detection rate was better with SPECT/CT than with lymphoscintigraphy in patients with stage I/II endometrial cancer.

Combining positron emission tomography/computed tomography, radiomics, and sentinel lymph node mapping for nodal staging of endometrial cancer patients

OBJECTIVE

To evaluate the combination of positron emission tomography/computed tomography (PET/CT) and sentinel lymph node (SLN) biopsy in women with apparent early-stage endometrial carcinoma. The correlation between radiomics features extracted from PET images of the primary tumor and the presence of nodal metastases was also analyzed.

METHODS

From November 2006 to March 2019, 167 patients with endometrial cancer were included. All women underwent PET/CT and surgical staging: 60/167 underwent systematic lymphadenectomy (Group 1) while, more recently, 107/167 underwent SLN biopsy (Group 2) with technetium-99m +blue dye or indocyanine green. Histology was used as standard reference. PET endometrial lesions were segmented (n=98); 167 radiomics features were computed inside tumor contours using standard Image Biomarker Standardization Initiative (IBSI) methods. Radiomics features associated with lymph node metastases were identified (Mann-Whitney test) in the training group (A); receiver operating characteristic (ROC) curves, area under the curve (AUC) values were computed and optimal cut-off (Youden index) were assessed in the test group (B).

RESULTS

In Group 1, eight patients had nodal metastases (13%): seven correctly ridentified by PET/CT true-positive with one false-negative case. In Group 2, 27 patients (25%) had nodal metastases: 13 true-positive and 14 false-negative. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of PET/CT for pelvic nodal metastases were 87%, 94%, 93%, 70%, and 98% in Group 1 and 48%, 97%, 85%, 87%, and 85% in Group 2, respectively. On radiomics analysis a significant association was found between the presence of lymph node metastases and 64 features. Volume-density, a measurement of shape irregularity, was the most predictive feature (p=0001, AUC=0,77, cut-off 0.35). When testing cut-off in Group B to discriminate metastatic tumors, PET false-negative findings were reduced from 14 to 8 (-43%).

CONCLUSIONS

PET/CT demonstrated high specificity in detecting nodal metastases. SLN and histologic ultrastaging increased false-negative PET/CT findings, reducing the sensitivity of the technique. PET radiomics features of the primary tumor seem promising for predicting the presence of nodal metastases not detected by visual analysis.

Sentinel lymph node mapping using SPECT/CT and gamma probe in endometrial cancer: an analysis of parameters affecting detection rate

PURPOSE

SPECT/CT after pericervical injection of technetium-99 m-nanocolloid was shown to be suitable for sentinel lymph node (SLN) mapping in endometrial cancer (EC). The aim of this study was to analyze factors affecting successful SLN detection by means of SPECT/CT such as imaging findings, patient characteristics and tumor biology in a large cohort of patients.

METHODS

One hundred and forty-five consecutive patients suffering from EC who received pre-surgical SLN mapping at our institution between 2011 and 2016 were included in this analysis. SPECT/CT data of abdomen and pelvis (mean 4:20 ± 1:20 h p.i.) were acquired after pericervical injection of technetium-99 m-nanocolloid (mean 230 ± 45 MBq) in all patients. Surgical staging was performed on the day after. Acquisition parameters, patient characteristics, SPECT/CT findings as well as histopathological results were collected.

RESULTS

A total of 282 SLNs were identified by means of SPECT/CT. Overall, preoperative and intraoperative SLN detection rates were 86%, 76% and 74% respectively. The most important factor associated with failure to detect SLNs was the presence of high bone marrow on SPECT/CT (p = 0.005). Peritoneal/abdominal radioactivity was also associated with missed SLN detection in SPECT/CT (p = 0.02). However, the presence of liver/spleen uptake on its own was not predictive for detection failure. Low numbers of detected SLNs in SPECT/CT were slightly related with older age and lower injected activity. No significant influence was found for the parameters of tumor histology and stage, lymph node involvement and the time gap between injection and imaging.

CONCLUSIONS

Venous drainage as indicated by bone marrow uptake is the most important factor associated with scintigraphic SLN detection failure. Moreover, high peritoneal and abdominal activity was also associated with detection failure. Thus, meticulous application of the radiotracer is crucial in EC.

Pericervical Injection of 99mTc-Nanocolloid Is Superior to Peritumoral Injection for Sentinel Lymph Node Detection of Endometrial Cancer in SPECT/CT

PURPOSE

Scintigraphic mapping of sentinel lymph node (SLN) is increasingly performed in patients with endometrial carcinoma although its routine clinical use is still under investigation. The purpose of this study was to compare preoperative SLN detection by means of SPECT/CT using pericervical (PC) versus hysteroscopic peritumoral (PT) injection.

PATIENTS AND METHODS

One hundred forty consecutive patients with endometrial carcinoma who underwent surgery and preoperative SLN SPECT/CT with Tc-nanocolloid were included. Seventy women received hysteroscopic injection at 3 PT sites, and 70 women received PC injection at 3-, 6-, 9-, and 12-o'clock positions. Each patient underwent SPECT/CT followed by modified radical hysterectomy with lymphadenectomy on the day after. Histopathological results were collected for validation.

RESULTS

Three hundred thirty-four SLNs were detected by SPECT/CT in 106 patients (mean, 3.15; range, 1-9). The detection rate after PC nanocolloid injection was 83% versus 69% after PT injection (Pearson χ test, P = 0.049). However, PT application resulted in a higher rate of para-aortic SLNs (PC: 60% vs PT: 38% of positive scans, P = 0.02). SPECT/CT yielded an overall sensitivity of 70% for the SLN detection in women with lymph node metastases with 3 false-negative cases. Failure to detect SLN was mostly associated with uptake in the reticuloendothelial system (liver, spleen, and bone marrow) or peritoneal diffusion in both cohorts. Negative scans after PT application often showed a minor to even failing injection depot.

CONCLUSIONS

Pericervical injection leads to a significantly better detection rate of SLN on SPECT/CT while reducing invasiveness of the injection procedure. Failure to detect SLN seems to be associated with major venous drainage.

Sentinel-node mapping in endometrial cancer patients: comparing SPECT/CT, gamma-probe and dye

OBJECTIVE

The aim of this study was to compare preoperative SPECT/CT with gamma-probe and methylene blue-dye (MBD) in the identification of sentinel lymph node (SLN) in early stage endometrial cancer.

METHODS

40 stage-I EC patients (66.7 ± 9.7 years) underwent preoperative lymphoscintigraphy. After about 3 h from Tc-99m-albumin nanocolloid cervical injection, all patients underwent SPECT/CT study. MBD was injected into the cervix just before surgery under general anesthesia. All patients underwent SLN biopsy, hysterectomy, bilateral salpingo-oophorectomy, and radical regional lymphadenectomy. SPECT/CT findings were compared to those of gamma-probe and MBD techniques.

RESULTS

In 2 patients no nodal migration was observed, neither with MBD nor radiotracer. Detection rate of at least one SLN was 90% (36/40 patients) with SPECT/CT, 88% (35/40) intra-operatively with gamma-probe and 80% (32/40) with MBD. Only in 7/40 patients a bilateral migration was obtained with all considered modalities. In particular, bilateral detection was achieved in 26 patients with SPECT/CT, in 24 with gamma-probe and in 10 patients with MBD. The concordance site between SPECT/CT and intraoperative gamma-probe was 73% (29/40 patients: 2 without migration, 21 bilateral and 6 monolateral SLNs); while concordance site with MBD was found in 40% (16/40: 8 bilateral, 6 monolateral SLNs, 2 without SLNs). Overall, 628 LNs were dissected (mean 18 LNs per patient). The median number of SLNs removed was 2 (mean 2.5 per patient). Out of 91 SLNs: 43 were "hot and blue (HB)", 10 were blue only and 38 were hot only. LN metastases rate was 16%: 9/90 SLNs (7 HB, 2 hot only) were positive for metastases in 6 patients. Four non-SLNs were found positive in 3 patients, and all presented concomitant positive SLNs. False negative rate was 0%.

CONCLUSIONS

SPECT/CT had the highest detection rate and achieved the highest rate of bilateral mapping, compared to gamma-probe and MDB. SPECT/CT had moderate concordance with gamma-probe, and it can help the intraoperative detection of SLNs providing important information about their anatomic location.

Optimizing Strategies for Sentinel Lymph Node Mapping in Early-Stage Cervical and Endometrial Cancer: Comparison of Real-Time Fluorescence With Indocyanine Green and Methylene Blue

OBJECTIVE

This retrospective study aimed to compare the sentinel lymph node (SLN) mapping results of methylene blue (MB) and indocyanine green (ICG) in women with early-stage endometrial or cervical cancer.

METHODS

From August 2011 to March 2015, all consecutive patients with stage I endometrial or cervical cancer who underwent SLN mapping with intracervical injection of MB or ICG using a 22-gauge spinal needle were included in the study. Radical or simple hysterectomy with bilateral pelvic and/or aortic lymphadenectomy was performed after SLN mapping.

RESULTS

Overall, 81 women (64 women with endometrial cancer and 17 women with cervical cancer) underwent surgery, including SLN mapping. Sixty-five patients (80%) underwent minimally invasive surgery. The overall detection rate was 84% (34 of 38) and 100% (43 of 43) for MB and ICG, respectively (P = 0.041). Bilateral SLN detection was higher in the ICG group than in the MB group (88% vs 50; P = 0.002). Eleven patients (13.5%) were found to have positive nodes with at least 1 positive SLN. The sensitivity and negative predictive value of SLN were 100%.

CONCLUSIONS

Real-time florescence mapping with ICG shows better overall detection rate and bilateral mapping than MB alone. In our pilot study, the differences are statistically significant. The higher number of bilateral mapping of ICG may increase the quality of life and recovery of women by reducing the need for complete lymphadenectomy.

The sentinel node approach in gynaecological malignancies

This review discusses the state-of-the-art of sentinel lymph node mapping in gynaecological malignancies, including cervical cancer, endometrial cancer, and vulvar cancer, with an emphasis on new technological advances. For this objective, PubMed/MEDLINE was searched for relevant studies about the sentinel lymph node procedure in gynaecology. In particular, the use of preoperative lymphatic mapping with lymphoscintigraphy and single photon emission tomography/computed tomography (SPECT/CT) was identified in 18 studies. Other recent advances as hybrid tracers (e.g. ICG-^99mTc-nanocolloid) and intraoperative tools (portable γ-camera and 3D navigation devices) appear to also represent a useful guide for the surgeon during the operation. Concerning vulvar and cervical cancers, the sentinel lymph node procedure has been incorporated to the current guidelines in Europe and North America, whereas for endometrial cancer it is considered investigative.

Quality of Care for Cervical and Endometrial Cancer Patients: The Impact of Different Techniques of Sentinel Lymph Node Mapping on Patient Satisfaction

OBJECTIVES

The purpose of this study was to assess the quality of care in patients who underwent sentinel lymph node (SLN) mapping for endometrial and cervical cancer staging, and evaluate the impact of different techniques on patient satisfaction, i.e. radiotracer Tc99m versus indocyanine green (ICG) or methylene blue injection.

METHOD

Women with preoperative stage I endometrial cancer or stage I (1A2-1B1) cervical cancer who underwent surgical staging, including SLN mapping, were considered for this study. Patient satisfaction was assessed using the European Organisation for Research and Treatment of Cancer IN-PATSAT32 questionnaire. Women were classified into two groups according to the different nodal mapping techniques: intracervical preoperative injection of Tc99m nanocolloid + intraoperative blue dye (Group 1) versus intraoperative cervical injection of ICG or blue dye (Group 2). Differences in patient satisfaction scores between the groups were analyzed.

RESULTS

Of the 178 eligible women, 143 were included in the study (endometrial cancer n = 106, cervical cancer n = 37): 57 underwent SLN mapping with Tc99m and blue dye (Group 1), and 86 women were mapped intraoperatively with blue dye alone or ICG (Group 2). Analysis of IN-PATSAT32 questionnaire scores showed a higher patient satisfaction score for patients in Group 2 (p = 0.001), which was independent of the physician and surgical outcomes evaluated. The scores were statistically better for Group 2, and also in rating doctors (p = 0.0001), nurses (p = 0.006), and care and services organizations (p = 0.001).

CONCLUSIONS

Cervical and endometrial cancer patients who underwent SLN mapping by ICG or blue dye perceived a better quality of care when compared with those patients who underwent the combined radiocolloid and blue dye technique.

Staging of High-Risk Endometrial Cancer With PET/CT and Sentinel Lymph Node Mapping

PURPOSE

The aim of this study was to evaluate the role of PET/CT and sentinel lymph node (SLN) biopsy in staging high-risk endometrial cancer patients (G2 and deep myometrial invasion, G3, serous clear cell carcinoma or carcinosarcoma) in early clinical stage.

PATIENTS AND METHODS

From January 2006 to December 2012, high-risk early-stage endometrial cancer patients performing PET/CT scan followed by surgery (systematic pelvic ± aortic lymphadenectomy) were included. From December 2010, SLN mapping with Tc-albumin nanocolloid and blue dye cervical injection was included in our clinical practice and additionally performed. Histological findings were used as the reference standard.

RESULTS

Ninety-three patients were included, of which 22 of 93 had both PET/CT and SLN biopsy. The median number of dissected lymph nodes (LNs) was 28. Nineteen women (20.4%) had pelvic LN metastases; 14 were correctly identified by PET/CT. Among 5 false-negative cases, 3 occurred after the introduction of SLN mapping due to detection of micrometastases by ultrastaging. On overall patient-based analysis, the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of PET/CT for pelvic LN metastases were 73.7%, 98.7%, 93.6%, 93.3%, 93.6%, respectively.

CONCLUSIONS

PET/CT demonstrated moderate sensitivity and high specificity in detecting pelvic LN metastases; its high positive predictive value (93.3%) is useful to refer patients to appropriate debulking surgery. Sentinel LN mapping and histological ultrastaging increased the identification of metastases (incidence, 18.3%-27.3%) not detectable by PET/CT because of its spatial resolution. The combination of both modalities is promising for nodal staging purpose.

Impact of Indocyanine Green for Sentinel Lymph Node Mapping in Early Stage Endometrial and Cervical Cancer: Comparison with Conventional Radiotracer (99m)Tc and/or Blue Dye

Purpose

To compare the detection rate (DR) and bilateral optimal mapping (OM) of sentinel lymph nodes (SLNs) in women with endometrial and cervical cancer using indocyanine green (ICG) versus the standard technetium-99m radiocolloid (^99mTc) radiotracer plus methylene or isosulfan blue, or blue dye alone.

Methods

From October 2010 to May 2015, 163 women with stage I endometrial or cervical cancer (118 endometrial and 45 cervical cancer) underwent SLN mapping with ^99mTc with blue dye, blue dye alone, or ICG. DR and bilateral OM of ICG were compared respectively with the results obtained using the standard ^99mTc radiotracer with blue dye, or blue dye alone.

Results

SLN mapping with ^99mTc radiotracer with blue dye was performed on 77 of 163 women, 38 with blue dye only and 48 with ICG. The overall DR of SLN mapping was 97, 89, and 100 % for ^99mTc with blue dye, blue dye alone, and ICG, respectively. The bilateral OM rate for ICG was 85 %—significantly higher than the 58 % obtained with ^99mTc with blue dye (p = 0.003) and the 54 % for blue dye (p = 0.001). Thirty-one women (19 %) had positive SLNs. Sensitivity and negative predictive value of SLN were 100 % for all techniques.

Conclusions

SLNs mapping using ICG demonstrated higher DR compared to other modalities. In addition, ICG was significantly superior to ^99mTc with blue dye in terms of bilateral OM in women with early stage endometrial and cervical cancer. The higher number of bilateral OM may consequently reduce the overall number of complete lymphadenectomies, reducing the duration and additional costs of surgical treatment.

Sentinel Lymph Node Mapping With Near-Infrared Fluorescent Imaging Using Indocyanine Green: A New Tool for Laparoscopic Platform in Patients With Endometrial and Cervical Cancer

Indocyanine green (ICG) represents a feasible alternative to the more traditional methods of sentinel lymph node (SLN) mapping, and interest in this promising tracer is growing. This report outlines our experience with ICG in a minimally invasive laparoscopic approach in women with endometrial cancer and cervical cancer using the Storz SPIES ICG near-infrared fluorescence imaging technology. A total of 49 patients with clinical stage I endometrial cancer (n = 40) or stage I cervical cancer (n = 9) were retrospectively reviewed. All patients had undergone simple or radical laparoscopic hysterectomy with pelvic and/or aortic lymphadenectomy and SLN mapping by means of an intracervical injection of ICG dye at the 3 o'clock and 9 o'clock locations after the induction of general anesthesia. The detection rate of ICG was 100% (49 of 49). The rate of bilateral SLN detection was 86% (42 of 49). Positive lymph nodes were found in 6 patients (12%), with at least 1 positive SLN. The sensitivity and negative predictive value of SLN detection were 100%. All procedures were successfully completed without conversion to open laparotomy, and no intraoperative or postoperative complications occurred. In our preliminary experience, ICG showed a high overall detection rate, and bilateral mapping appears to be a feasible alternative to the more traditional methods of SLN mapping in patients with endometrial cancer and cervical cancer. Laparoscopic SLN mapping with ICG appears to be safe, easy, and reproducible, with a positive impact on patient management.

Sentinel Lymph Node Biopsy in Endometrial Cancer--Comparison of 2 Detection Methods

OBJECTIVES

Sentinel lymph node biopsy (SLNB) can identify patients with nodal metastases who are eligible for tailored treatment. The aim of study was to compare the SLN detection rates using cervical and subserosal administration of 2 tracers.

RESULTS

In group 1 (82 patients), SLNB was performed using radiocolloid injected to the cervix and blue dye administered to the fundus. In group 2, blue dye was injected to cervix and fundus (106 patients). Only SLNB was performed in 128 (68.1%) women. In the remaining 60 (31.9%) patients, pelvic/para-aortic lymphadenectomy together with SLNB was performed. Groups 1 and 2 did not differ with regard to the frequencies of SLNB and lymphadenectomy. The detection rate for both groups was 90.9%. Bilateral detection was achieved in 72.5%. Para-aortic SLNs were found in 9.6%. Detection rates in groups 1 and 2 were 95.1% and 87.7% (P = 0.065). In comparison of cervical administration of radioisotope and subserosal injection of blue dye in group 1, we found a significant difference for total SLN detection (91.5% vs 74.4%, P < 0.05) and no significant difference for bilateral detection (73.3% vs 59.1%, P = 0.776). We did not find differences in the para-aortic SLN detection rates achieved after administration of a radiotracer and injection of a blue dye (4.9% vs 9.8%, P = 0.184). Eighteen patients (9.6%) presented with nodal disease, including 15 women with SLN involvement. The false-negative rate, calculated for patients subjected to lymphadenectomy, was 12.5% (1/8); using the SLNB surgical algorithm, it was 10% (1/10).

CONCLUSIONS

Cervical administration of a tracer, especially radioisotope, results in high SLN detection rates. In turn, the subserosal injection can be used only as an adjuvant method for SLNB. Low para-aortic SLN detection rates observed after cervical administration of a tracer do not seem to be a serious limitation of this technique.

99mTc SPECT/CT Versus Planar Lymphoscintigraphy for Preoperative Sentinel Lymph Node Detection in Cervical Cancer: A Systematic Review and Metaanalysis

We aimed to compare SPECT/CT and lymphoscintigraphy on overall and bilateral sentinel lymph node (SLN) detection in cervical cancer patients.

METHODS

A systematic search was performed on August 1, 2014, in PubMed, Embase, Scopus, and the Cochrane library. The syntax was based on synonyms of the terms cervical cancer, SPECT/CT, and lymphoscintigraphy. Retrieved articles were screened on their title/abstract and considered eligible when an SLN procedure was performed using both imaging modalities and if detection results were reported. Two independent reviewers assessed all included studies on methodologic quality using QUADAS-2. Studies were pooled on their odds ratios (ORs) with a random-effects model.

RESULTS

The search yielded 962 unique articles, of which 8 were ultimately included. The studies were recent retrospective or prospective cohort studies of limited size (n = 7-51) but sufficient methodologic quality. The median overall detection (≥1 SLN in a patient) was 98.6% for SPECT/CT (range, 92.2%-100.0%) and 85.3% for lymphoscintigraphy (range, 70.0%-100.0%). This corresponded to a pooled overall SLN detection OR of 2.5 (95% CI, 1.2-5.3) in favor of SPECT/CT. The reported median bilateral detection (≥1 SLN in each hemipelvis) was 69.0% for SPECT/CT (range, 62.7%-79.3%) and 66.7% for lymphoscintigraphy (range, 56.9%-75.8%), yielding a pooled OR of 1.2 (95% CI, 0.7-2.1). No significant difference in the number of visualized SLNs was observed at a pooled ratio of 1.2 (95% CI, 0.9-1.6).

CONCLUSION

In cervical cancer patients, preoperative SLN imaging with SPECT/CT results in superior overall SLN detection in comparison with planar lymphoscintigraphy.

Feasibility and performance of lymphoscintigraphy in sentinel lymph node biopsy for early cervical cancer: results of the prospective multicenter SENTICOL study

Objective

To evaluate feasibility, SLN detection rate, and SLN location of lymphoscintigraphy in sentinel lymph node (SLN) biopsy for early cervical cancer.

Methods

Ancillary analysis of data from the multicenter prospective SENTICOL study (January 2005–June 2007) of patients with early cervical cancer (FIGO stage IA with emboli to IB1) was conducted. Preoperative lymphoscintigraphy was performed after intracervical administration of 60 or 120 MBq of ^99mTc-labeled radiocolloid on the day before (long protocol) or morning of (short protocol) surgery. SLNs were identified intraoperatively using combined radioactivity/patent blue detection. SLNs were sampled electively and routine bilateral pelvic lymphadenectomy was performed by laparoscopy. A centralized review of lymphoscintigraphies was performed to assess feasibility, detection rates, and anatomic SLN location.

Results

Of 139 patients included in the SENTICOL study, 133 received radiocolloid injection, and 131 (98.5 %) underwent preoperative lymphoscintigraphy, with the long protocol in three-fourths of cases. The lymphoscintigraphic detection rate was 87.8 %, with a median of 2 (1–4) SLNs per patient. By multivariate analysis, factors independently associated with lymphoscintigraphic SLN detection were age [odds ratio (OR) 0.91, 95 % confidence interval (95 % CI) 0.87–0.96; P < 0.001], and protocol (long vs. short; OR 8.23, 95 % CI 1.87–36.25; P = 0.005). Bilateral SLN identification by lymphoscintigraphy occurred in 67 % of cases and was independently influenced by age (OR 0.95, 95 % CI 0.92–0.98, P < 0.001) and protocol (OR 5.42, 95 % CI 2.21–13.27; P < 0.001). Although 60.5 % of preoperative SLNs were in the external iliac territory, unusual drainage patterns included the common iliac (19.6 %), para-aortic (10.8 %), and parametrial (6 %) basins.

Conclusions

Our study demonstrates the feasibility and good detection rate of preoperative lymphoscintigraphy, with better detection in younger patients and with the long protocol. The high proportion of SLN basins in unexpected territories is of interest to guide intraoperative detection. Further studies are needed to better evaluate preoperative detection and to assess the contribution of lymphoscintigraphy to intraoperative detection.

Isthmocervical labelling and SPECT/CT for optimized sentinel detection in endometrial cancer: technique, experience and results

OBJECTIVE

We evaluated the clinical feasibility of a new injection technique for sentinel detection in endometrial carcinoma (EC), transcervical subepithelial injection into the isthmocervical region of the myometrium. We compared detection of sentinel lymph nodes (SLN) by single photon emission computed tomography with CT (SPECT/CT) with planar lymphoscintigraphy.

METHODS

This is a unicentric prospective study. In all patients, transcervical injection of 10 MBq Technetium-99m-nanocolloid was performed into the isthmocervical myometrium without anaesthesia. After 40 (30-60) min, lymphoscintigraphy and SPECT/CT were performed. Patent blue was administered before surgery. The number and localisation of SLN detected in SPECT/CT and lymphoscintigraphy were recorded and compared to the SLN and non-SLN dissected intra-operatively.

RESULTS

Between August 2008 and March 2012, 31 patients with EC were enrolled. The new transcervical injection of labelling substances led to high intra-operative (90.3%) detection rates, pelvic bilateral (57%), para-aortic (25%). SPECT/CT significantly identified more SLN than lymphoscintigraphy (mean 2.2 (1-8) to 1.3 (1-7)) in more patients (29/31 (93.5%) to 21/31 (68%), p<0.01). If SLN were identified in one hemi-pelvis, the histological evaluation of the SLN correctly predicted lymph node (LN) metastases for this basin which led to sensitivity 100%, negative predictive value (NPV) 100%, and false negative results 0%.

CONCLUSION

Transcervical SLN marking in combination with SPECT/CT is easily applicable and leads to high physiologic detection rates in pelvic and para-aortic lymphatic drainage areas. Non-affected SLN truly predicted a non-affected LN basin. Combining both methods SLN dissection may be a safe and feasible staging technique for clinical routine in EC.

Preoperative detection of sentinel lymph nodes in endometrial cancer using SPECT/CT

We report the use of SPECT/CT in sentinel lymph node biopsy in endometrial cancer. The patient was a 54-year-old woman with the diagnosis of endometrial adnenocarcinoma, grade 2. Preoperative MRI and transvaginal ultrasound scans revealed tumor infiltrating more than 50% of the myometrium. The patient was qualified for total abdominal hysterectomy, bilateral salpingo-oophorectomy, and pelvic/paraaortic lymphadenectomy. Before the surgery, 2 cervical injections of the (99m)Tc-labeled nanocolloid (0.5 mCi) were administered and the SPECT/CT was performed using a standard dual-head gamma camera and a 6-slice spiral CT component.

Value and advantages of preoperative sentinel lymph node imaging with SPECT/CT in cervical cancer

OBJECTIVE

Precise detection of sentinel lymph nodes (SLNs) seems to be a crucial factor for optimized treatment of cervical cancer. We assess the use of single photon emission computed tomography combined with computed tomography (SPECT/CT) as an alternative to lymphoscintigraphy (LSG) for preoperative identification of SLN.

METHODS

This study was performed in a prospective, unicentric setting. Patients with cervical carcinoma were scheduled for surgery and additional SLN labeling by peritumoral injection of 10 MBq technetium-99m-nanocolloid and patent blue. Thirty minutes after injection, LSG and SPECT/CT were carried out. We evaluated the number of SLNs detected intraoperatively in LSG and SPECT/CT and the histologic findings of SLN and non-SLN. Subsequently, we determined the impact of these results on the therapeutic approach.

RESULTS

This represents the largest study about SPECT/CT for SLN detection in cervical cancer so far. Between August 2008 and March 2013, 59 cervical cancer patients underwent intraoperative SLN detection. In addition, 51 of these patients underwent preoperative LSG and SPECT/CT. Imaging with SPECT/CT detected singular SLN at significantly higher rate (47/51, 92.2%) than that with planar LSG (43/51, 84.3%, P = 0.044). Furthermore, SPECT/CT performed better than LSG regarding the total number of detected SLN (SPECT/CT median, 3 [0-18]; LSG median, 2 [0-15]) and detection rates per pelvic side (SPECT/CT 76.9%, LSG 69.2%, P < 0.01). Whenever SLN detection succeeded, histologic evaluation of SLN correctly predicted the lymph node status per patient's side. Using this type of diagnostic approach for lymph node staging, we reached sensitivity of 100% and negative predictive value of 100% at a rate of false-negative results of 0% even in tumors larger than 4 cm.

CONCLUSIONS

Single photon emission computed tomography combined with computed tomography imaging leads to improved rates of SLN detection and better anatomic correlation compared with planar LSG. Thus, intraoperative detection of SLN can be improved by preoperative SPECT/CT imaging. This enhances the clinical value of SLN technique and improves the oncologic safety of SLN concept.

Is sentinel lymph node dissection an appropriate standard of care for low-stage endometrial cancers? A review of the literature

BACKGROUND/AIMS

To review the literature and compare detection rates, false negative (FN) rates, and negative predictive values (NPVs) of sentinel lymph node (SLN) biopsy in endometrial cancer to those in breast and vulvar cancer. Secondary objectives were to evaluate techniques of SLN biopsy in endometrial cancer.

METHODS

The PubMed database was searched for applicable scientific articles. Detection rates, FN rates, and NPVs were calculated for all studies. Studies were stratified by techniques and compared.

RESULTS

Nineteen articles met criteria for this review. The overall detection rates ranged from 62 to 100%, the FN rate ranged from 0 to 50%, and the NPVs ranged from 95 to 100%. There is no technique that is definitively superior to any other with regard to surgical modality, injectant used, injection site, or pathologic techniques.

CONCLUSIONS

Studies on SLN biopsy in endometrial cancer have a large range of detection rates and FN rates, and larger studies including more patients with metastatic disease are needed for comparison with breast and vulvar cancers. While no techniques are definitively superior to others, minimally invasive surgery, cervical injection, and pathologic analysis utilizing HE staining, immunohistochemistry, and ultrastaging may be clinically advantageous.

Sentinel node mapping in high risk endometrial cancer after laparoscopic supracervical hysterectomy with morcellation

INTRODUCTION

Occult endometrial cancer after supracervical hysterectomy is very uncommon. Even if optimal management of those rare cases is still unproven, to guide the need for further therapies, restaging should be recommended in this situation.

PRESENTATION OF CASE

We report of a 60-year old woman with occult high risk endometrial cancer after supracervical hysterectomy with morcellation. We describe the feasibility of laparoscopic intraoperative sentinel node identification with cervical stump removing to restage the suspicious early stage high risk endometrial cancer.

DISCUSSION

In high risk endometrial cancer surgical restaging is important, considering that 10-35% of cases can present pelvic nodal metastasis. To reduce the treatment related morbidity maintaining the benefit of surgical staging, with a negative preoperative PET/CT, we performed a laparoscopic SN mapping with cervical stump removing.

CONCLUSION

This report highlight the fact that SN mapping with cervical injection is a feasible and safe technique also without the uterine corpus after supracervical hysterectomy with morcellation.

Uterine lymphatic drainage is unaffected from injection technique and operators: Identical sentinel node detection in two cases of endometrial cancer

INTRODUCTION

Sentinel node (SN) mapping with cervical injection of 99m-technetium (99mTc) albumin nanocolloid in early endometrial cancer has been shown to be feasible and data emerging from recent large series support the incorporation of SN mapping algorithm in endometrial cancer staging.

PRESENTATION OF CASE

We report two cases of SN mapping which demonstrated identical migration of both radioactive technetium and blue dye in the same patients that were re-injected because surgical intervention was postponed due to transitory cardiac contraindications.

DISCUSSION

As clearly demonstrated in cervical cancer, SN mapping through intracervical injection of both radioactive technetium and blue dye seems to be effective and easy to perform, providing good results in patients with endometrial cancer. Our report highlights the reproducibility of SN mapping that has been strongly confirmed in both patients, even if re-injections were performed by different operators. Preoperative SPECT/CT imaging seems to enhance accuracy in SN localization and also improves its intraoperative detection in early endometrial cancer.

CONCLUSION

The anatomically defined bilateral uterus drainage strongly confirms the reproducibility of SN mapping, that seems to be unaffected by after injection technique or operators.

Use of SPECT/CT for improved sentinel lymph node localization in endometrial cancer

OBJECTIVE

To assess the usefulness of adding SPECT/CT to planar images for pre-surgical sentinel lymph node (SLN) identification in endometrial cancer (EC), a technique that could have an important clinical impact on the staging, treatment, and prognosis of EC patients.

METHODS

We compared the planar and SPECT/CT lymphoscintigraphic images of 44 patients with high-risk EC who underwent sentinel lymph node procedure (SLN) using an injection technique recently developed at our center known as TUMIR (Transvaginal Ultrasound Myometrial Injection of Radiotracer). 148 MBq (4 mCi) of 99mTc-nanocolloid were injected, guided by transvaginal ultrasound imaging. Planar and SPECT/CT images were performed in all 44 patients.

RESULTS

SLNs were seen on planar images in 32 cases (73%) and in 34 cases (77%) using SPECT/CT. A total of 88 SLNs were depicted by planar lymphoscintigraphy while SPECT/CT visualized a total of 110 SLNs. SPECT/CT changed the assessment of the SLNs visualized in planar lymphoscintigraphy in 26 cases, either by modifying the number and/or the location of the SLNs detected. External iliac chain was the most frequent location of SLN detection (71%) in the 34 cases. Fifteen of these patients (44%) showed para-aortic SLNs. One case had exclusive para-aortic drainage (3%) that was only visualized by SPECT/CT. In another case, SPECT/CT was able to localize the only pelvic metastatic lymph node not visualized by planar images.

CONCLUSIONS

SPECT/CT combined with planar imaging improves preoperative SLN detection and provides valuable anatomic information that enhances the presurgical stage of the SLN technique in endometrial cancer.