The EANM clinical and technical guidelines for lymphoscintigraphy and sentinel node localization in gynaecological cancers

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.

Setting-up a training programme for intraoperative molecular imaging and sentinel node mapping: how to teach? How to learn?

BACKGROUND

The current expansion of image-guided surgery is closely related to the role played by radio-guided surgery in supporting the sentinel node (SN) procedure during more than three decades. The so-called triple approach (lymphoscintigraphy, gamma probe detection and blue dye) was not only essential in the seminal validation of the SN procedure but also a first collective learning effort based on skill transfer and outcome-related evaluation which laid the fundaments to delineate the field of intraoperative molecular imaging (IMI) based on a similar multimodality approach and multidisciplinary practice.

METHODS

These elements are also becoming valid in the current incorporation of SPECT/CT and PET/CT to existing and new protocols of IMI procedures and SN mapping concerning other clinical applications. On the other hand, there is a growing tendency to combine novel modern technologies in an allied role with gamma guidance in the operating room following the development of hybrid tracers and multimodal detection approaches. Against this background, learning initiatives are required for professionals working in this area.

RESULTS

This objective has led to a group of European practitioners with large experience in SN mapping and IMI applications to give shape to a programme made up out of specific learning modules aimed to be used as a conductive thread in peripherical or centralised training instances concerning the topic.

CONCLUSION

The presented work, written as a tutorial review, is placed in an available prior-art context and is primarily aimed at medical and paramedical practitioners as well as at hardware and software developers.

[Nuclear medicine procedure guideline for sentinel lymph node localization]

The authors present a procedure guideline for scintigraphic detection of sentinel lymph nodes in malignant melanoma, in breast cancer, in penile and vulva tumors, in head and neck cancer, and in prostate carcinoma. Important goals of sentinel lymph node scintigraphy comprise reduction of the extent of surgery, lower postoperative morbidity and optimization of histopathological examination focussing on relevant lymph nodes. Sentinel lymph node scintigraphy itself does not diagnose tumorous lymph node involvement and is not indicated when lymph node or distant metastases have been definitely diagnosed before sentinel lymph node scintigraphy. Procedures are compiled with the aim to reliably localise sentinel lymph nodes with a high detection rate typically in early tumour stages. New aspects in this guideline are new radiopharmaceuticals such as tilmanocept and Tc-99m-PSMA and SPECT/CT allowing an easier anatomical orientation. Initial dynamic lymphoscintigraphy in breast cancer is of little significance nowadays. Radiation exposure is low so that pregnancy is not a contraindication for sentinel lymph node scintigraphy. A one-day protocol should preferentially be used. Even with high volumes of scintigraphic sentinel lymph node procedures surgeons, theatre staff and pathologists receive a radiation exposure < 1 mSv/year so that they do not require occupational radiation surveillance. Aspects of quality control were included (scintigraphy, quality control of gamma probe, 6 h SLN course for surgeons, certified breast centers, medical surveillance center).

Sentinel Node Mapping in Ovarian Tumors: A Study Using Lymphoscintigraphy and SPECT/CT

Purpose

Ovarian cancer in the early stage requires a complete surgical staging, including radical lymphadenectomy, implying subsequent risk of morbidity and complications. Sentinel lymph node (SLN) mapping is a procedure that attempts to reduce radical lymphadenectomy-related complications and morbidities. Our study evaluates the feasibility of SLN mapping in patients with ovarian tumors by the use of intraoperative Technetium-99m-Phytate (Tc-99m-Phytate) and postoperative lymphoscintigraphy using tomographic (single-photon emission computed tomography/computed tomography (SPECT/CT)) acquisition.

Materials and Methods

Thirty-two patients with ovarian mass participated in this study. Intraoperative injection of the radiopharmaceutical was performed just after laparotomy and before the removal of tumor in utero-ovarian and suspensory ligaments of the ovary just beneath the peritoneum. Subsequently, pelvic and para-aortic lymphadenectomy was performed for malignant masses, and the presence of tumor in the lymph nodes was assessed through histopathological examination. Conversely, lymphadenectomy was not performed in patients with benign lesions or borderline ovarian tumors. Lymphoscintigraphy was performed within 24 hr using tomographic acquisition (SPECT/CT) of the abdomen and pelvis.

Results

Final pathological examination showed 19 patients with benign pathology, 5 with borderline tumors, and 6 with malignant ovarian tumors. SPECT/CT identified SLNs in para-aortic-only areas in 6 (20%), pelvic/para-aortic areas in 14 (47%), and pelvic-only areas in 7 (23%) cases. Notably, additional unusual SLN locations were revealed in perirenal, intergluteal, and posterior to psoas muscle regions in three patients. We were not able to calculate the false negative rate due to the absence of patients with involved lymph nodes.

Conclusion

SLN mapping using intraoperative injection of radiotracers is safe and feasible. Larger studies with more malignant cases are needed to better evaluate the sensitivity of this method for lymphatic staging of ovarian malignancies.

Speculation on optimal numbers of examined lymph node for early-stage epithelial ovarian cancer from the perspective of stage migration

Introduction

In early-stage epithelial ovarian cancer (EOC), how to perform lymphadenectomy to avoid stage migration and achieve reliable targeted excision has not been explored in depth. This study comprehensively considered the stage migration and survival to determine appropriate numbers of examined lymph node (ELN) for early-stage EOC and high-grade serous ovarian cancer (HGSOC).

Methods

From the Surveillance, Epidemiology, and End Results database, we obtained 10372 EOC cases with stage T1M0 and ELN ≥ 2, including 2849 HGSOC cases. Generalized linear models with multivariable adjustment were used to analyze associations between ELN numbers and lymph node stage migration, survival and positive lymph node (PLN). LOESS regression characterized dynamic trends of above associations followed by Chow test to determine structural breakpoints of ELN numbers. Survival curves were plotted using Kaplan-Meier method.

Results

More ELNs were associated with more node-positive diseases, more PLNs and better prognosis. ELN structural breakpoints were different in subgroups of early-stage EOC, which for node stage migration or PLN were more than those for improving outcomes. The meaning of ELN structural breakpoint varied with its location and the morphology of LOESS curve. To avoid stage migration, the optimal ELN for early-stage EOC was 29 and the minimal ELN for HGSOC was 24. For better survival, appropriate ELN number were 13 and 8 respectively. More ELNs explained better prognosis only at a certain range.

Discussion

Neither too many nor too few numbers of ELN were ideal for early-stage EOC and HGSOC. Excision with appropriate numbers of lymph node draining the affected ovary may be more reasonable than traditional sentinel lymph node resection and systematic lymphadenectomy.

A hybrid radioactive and fluorescence approach is more than the sum of its parts; outcome of a phase II randomized sentinel node trial in prostate cancer patients

OBJECTIVE

To determine the diagnostic accuracy of the hybrid tracer indocyanine green (ICG)-Technetium-99 m(99mTc)-nanocolloid compared to sequential tracers of 99mTc-nanocolloid and free-ICG in detecting tumor-positive lymph nodes (LN) during primary surgery in prostate cancer (PCa) patients.

INTRODUCTION

Image-guided surgery strategies can help visualize individual lymphatic drainage patterns and sentinel lymph nodes (SLNs) in PCa patients. For lymphatic mapping radioactive, fluorescent and hybrid tracers are being clinically exploited. In this prospective randomized phase II trial, we made a head-to-head comparison between ICG-99mTc-nanocolloid (hybrid group) and 99mTc-nanocolloid and subsequent free-ICG injection (sequential group).

METHODS

PCa patients with a  >5% risk of lymphatic involvement according to the 2012 Briganti nomogram and planned for prostatectomy were included and randomized (1:1) between ultrasound-guided intraprostatic tracer administration of ICG-99mTc-nanocolloid (n = 69) or 99mTc-nanocolloid (n = 69) 5 h before surgery. Preoperative lymphoscintigraphy and SPECT/CT were performed to define the locations of the SLNs. Additionally, all participants in the sequential group received an injection of free-ICG at time of surgery. Subsequently, all (S)LNs were dissected using fluorescence guidance followed by an extended pelvic lymph node dissection (ePLND). The primary outcome was the total number of surgically removed (S)LNs and tumor-positive (S)LNs.

RESULTS

The total number of surgically removed (S)LN packages was 701 and 733 in the hybrid and sequential groups, respectively (p = 0.727). The total number of fluorescent LNs retrieved was 310 and 665 nodes in the hybrid and sequential groups, respectively (p < 0.001). However, no statistically significant difference was observed in the corresponding number of tumor-positive nodes among the groups (44 vs. 33; p = 0.470). Consequently, the rate of tumor-positive fluorescent LNs was higher in the hybrid group (7.4%) compared to the sequential group (2.6%; p = 0.002), indicating an enhanced positive predictive value for the hybrid approach. There was no difference in complications within 90 days after surgery (p = 0.78).

CONCLUSIONS

The hybrid tracer ICG-99mTc-nanocolloid improved the positive predictive value for tumor-bearing LNs while minimizing the number of fluorescent nodes compared to the sequential tracer approach. Consequently, the hybrid tracer ICG-99mTc-nanocolloid enables the most reliable and minimal invasive method for LN staging in PCa patients.

Lymphatic mapping for image-guided radiotherapy in patients with locally advanced uterine cervical cancer: a feasibility study

BACKGROUND

Lymph node metastasis is an important prognostic factor in locally advanced cervical cancer (LACC). No imaging method can successfully detect all (micro)metastases. This may result in (lymph node) recurrence after chemoradiation. We hypothesized that lymphatic mapping could identify nodes at risk and if radiation treatment volumes are adapted based on the lymphatic map, (micro)metastases not shown on imaging could be treated. We investigated the feasibility of lymphatic mapping to image lymph nodes at risk for (micro)metastases in LACC and assessed the radiotherapy dose on the nodes at risk.

METHODS

Patients with LACC were included between July 2020 and July 2022. Inclusion criteria were: ≥ 18 years old, intended curative chemoradiotherapy, investigation under anesthesia. Exclusion criteria were: pregnancy and extreme obesity. All patients underwent abdominal MRI, [¹⁸F]FDG-PET/CT and lymphatic mapping after administration of 6-8 depots of ^99mTc]Tc-nanocolloid followed by planar and SPECT/CT images 2-4 and 24 h post-injection.

RESULTS

Seventeen patients participated. In total, 40 nodes at risk were visualized on the lymphatic map in 13/17 patients with a median of two [range 0-7, IQR 0.5-3] nodes per patient, with unilateral drainage in 4/13 and bilateral drainage in 9/13 patients. No complications occurred. The lymphatic map showed more nodes compared to suspicious nodes on MRI or [¹⁸F]FDG-PET/CT in 8/14 patients. Sixteen patients were treated with radiotherapy with 34 visualized nodes on the lymphatic map. Of these nodes, 20/34 (58.8%) received suboptimal radiotherapy: 7/34 nodes did not receive radiotherapy at all, and 13/34 received external beam radiotherapy (EBRT), but no simultaneous integrated boost (SIB).

CONCLUSION

Lymphatic mapping is feasible in LACC. Almost 60% of nodes at risk received suboptimal treatment during chemoradiation. As treatment failure could be caused by (micro)metastasis in some of these nodes, including nodes at risk in the radiotherapy treatment volume could improve radiotherapy treatment outcome in LACC. Trail registration The study was first registered at the International Clinical Trial Registry Platform (ICTRP) under number of NL9323 on 4 March 2021. Considering the source platform was not operational anymore, the study was retrospectively registered again on February 27, 2023 at CilicalTrials.gov under number of NCT05746156.

Hot or not? Investigating radiation safety and policy updating for the appropriate storage of radioactive specimens at Mount Sinai Hospital

PURPOSE

The current hospital policy for this study is stringent regarding the storage of radioactive sentinel lymph node (SLN) specimens, which requires the storage time of 24 hours before being handled by Pathology. Additional labeling along with separate containment of these specimens can be forgone if negligible radiation levels are found. The objective of this study was to determine whether the storage time needed for resected radioactive breast and primary site specimens to decay to twice the background radiation levels is less than 24 hours.

METHODS

The investigators retrieved breast and primary site SLN specimens from the Pathology department on the same day of the biopsy. A dose calibrator was used to measure the dose, specimen, and concurrent background radioactivity in Megabecquerels (MBq). Radioactive decay calculations were used to further investigate when specimen activities reached twice the background levels. A retrospective analysis was performed using a one-sample t-test to determine if the time to reach double the background activity was significantly different from 24 hours. This study pertained to workflow optimization; thus, general procedure consent forms were sufficient. Both patient confidentiality and privacy were protected. The investigators followed the necessary radiation safety measures.

RESULTS

The mean time for specimens to reach twice the background level of radioactivity was 3.99 hours, significantly less than current storage time of 24 hours (p < 0.001). The mean time point for the SLNs to reach 1/16th of the original activity was 7.78 hours (p < 0.001). The average node activity was 0.14 MBq.

CONCLUSION

The average sentinel node activity was less than 1 exemption quantity and the time to reach less than twice the background levels was significantly less than 24 hours, meaning that radioactive labels are not needed, and the 24-hour overnight specimen storage can be mitigated.

Lymphatic mapping and sentinel node biopsy in vulvar melanoma: the first multicenter study and systematic review

OBJECTIVE

This multicenter study aimed to investigate the role of preoperative lymphatic mapping and sentinel node biopsy (SNB) as well as the impact of negative SNB on loco-regional control and survival in vulvar melanoma patients with clinically negative nodes (cN0).

METHODS

Patients who had a proven vulvar melanoma with a Breslow thickness of 1-4 mm, cN0 and underwent a preoperative lymphatic mapping followed by SNB between July 2013 and March 2021 were retrospectively included. Groin recurrence and mortality rate were calculated as absolute and relative frequency. Disease-free survival (DFS) and overall survival (OS) were assessed by the Kaplan-Meier method. We provided a systematic review, searching among PubMed/Medline and Embase libraries. A total of 6 studies were identified (48 patients).

RESULTS

A total of 18 women were included. Preoperative planar images showed 51 SNs in 28 groins. Additional SPECT/CT images were acquired in 5/18 cases; SNs were identified pre- and intra-operatively in all cases. A total of 65 SNs were excised from 28 groins. A total of 13/18 (72.2%) patients (21/28 groins, 75%) had negative SNs with no groin recurrences and 12/13 (92.3%) were still alive at last follow-up. Five out of the 18 (27.8%) patients (7/28 groins, 25%) had positive SNs, 2/5 (40%) patients died of cancer after 26.2 and 33.8 months, respectively. The median DFS and OS for the entire cohort were 17.9 months (95% CI, 10.3-19.9) and 65.0 months (95% CI, 26.2-infinite), respectively. The probability of DFS and OS at 3 years were 15.5% (95% CI, 2.6-38.7) and 64.3% (95% CI, 15.5-90.2), respectively.

CONCLUSIONS

The use of preoperative lymphatic mapping followed by SNB permits a precise and minimally invasive surgical approach in cN0 vulvar melanoma patients. Negative SNB is associated with low risk of groin relapse and good survival.

A Review of Nuclear Medicine Approaches in the Diagnosis and the Treatment of Gynecological Malignancies

Nuclear medicine is defined as the diagnosis and the treatment of disease using radiolabeled compounds known as radiopharmaceuticals. Single-photon emission computed tomography/computed tomography (SPECT/CT) and positron emission tomography/computer tomography (PET/CT) based radiopharmaceuticals have proven reliable in diagnostic imaging in nuclear medicine and cancer treatment. One of the most critical cancers that also relies on an early diagnosis is gynecological cancer. Given that approximately 25% of all cancers in developing countries are a subset of gynecological cancer, investigating this cancer subtype is of significant clinical worth, particularly in light of its high rate of mortality. With accurate identification of high grade distant abdominal endometrial cancer as well as extra abdominal metastases, 18F-Fluorodeoxyglucose ([18F]FDG) PET/CT imaging is considered a valuable step forward in the investigation of gynecological cancer. Considering these factors, [18F]FDG PET/CT imaging can assist in making management of patient therapy more feasible. In this literature review, we will provide a short overview of the role of nuclear medicine in the diagnosis of obstetric and gynecological cancers.

"Clock mapping" prior to excisional surgery in vulvar Paget's disease: tailoring the surgical plan

INTRODUCTION

Paget disease is a rare neoplasm of the skin that mainly involves the vulvar region. Vulvar Paget's disease (VPD) can spread beyond the apparent edges of the lesion resulting in a high risk of involved surgical margins. Our aim is to verify the efficacy of a preoperative vulvo-vaginal intensive clock mapping in the prediction of the invasiveness and the extension of VPD.

MATERIALS AND METHODS

All consecutive patients with primary VPD referred to our institution from July 2005 to December 2018 were subjected to a preoperative intensive biopsy mapping (clock mapping) of the vulvo-vaginal area: inside and outside the vulvar skin visible lesion, according to o'clock positions, and in the vagina. Patients with positive biopsies "only inside" or "also beyond" the visible lesion were included, respectively, in Group A and B. Surgical excision was drawn passing by the points with negative histology. Pathological findings of mapping biopsies were compared with those from radical surgery.

RESULTS

A total of 28 women were enrolled. After clock mapping definitive histology: 17 (60.7%) and 11 (39.3%) patients were included in Group A and B. Definitive histology showed non-invasive, micro-invasive and invasive VPD, respectively, in 13 (46.4%), 11 (39.3%) and 4 (14.3%) patients, with 4 patients further upstaged. Overall, negative margins were found in 14 (50%) patients: 9 (32.1%) from Group A and 5 (17.9%) from Group B. In 23 cases (82.1%), clock mapping identified free surgical margins along the vulvo-perineal skin excision front.

CONCLUSIONS

Preoperative clock mapping emerged as potentially useful workup tool to predict invasiveness and extension of VPD, to tailor surgical excision.

Oncologic Imaging of the Lymphatic System: Current Perspective with Multi-Modality Imaging and New Horizon

The lymphatic system is an anatomically complex vascular network that is responsible for interstitial fluid homeostasis, transport of large interstitial particles and cells, immunity, and lipid absorption in the gastrointestinal tract. This network of specially adapted vessels and lymphoid tissue provides a major pathway for metastatic spread. Many malignancies produce vascular endothelial factors that induce tumoral and peritumoral lymphangiogenesis, increasing the likelihood for lymphatic spread. Radiologic evaluation for disease staging is the cornerstone of oncologic patient treatment and management. Multiple imaging modalities are available to access both local and distant metastasis. In this manuscript, we review the anatomy, physiology, and imaging of the lymphatic system.

Women-specific routes of administration for drugs: A critical overview

The woman's body presents a number of unique anatomical features that can constitute valuable routes for the administration of drugs, either for local or systemic action. These are associated with genitalia (vaginal, endocervical, intrauterine, intrafallopian and intraovarian routes), changes occurring during pregnancy (extra-amniotic, intra-amniotic and intraplacental routes) and the female breast (breast intraductal route). While the vaginal administration of drug products is common, other routes have limited clinical application and are fairly unknown even for scientists involved in drug delivery science. Understanding the possibilities and limitations of women-specific routes is of key importance for the development of new preventative, diagnostic and therapeutic strategies that will ultimately contribute to the advancement of women's health. This article provides an overview on women-specific routes for the administration of drugs, focusing on aspects such as biological features pertaining to drug delivery, relevance in current clinical practice, available drug dosage forms/delivery systems and administration techniques, as well as recent trends in the field.

Head-to-head comparison of the hybrid tracer indocyanine green-99mTc-nanocolloid with 99mTc-Senti-Scint using sentinel node lymphoscintigraphy and single-photon emission computed tomography combined with computer tomography in melanoma

OBJECTIVE

The hybrid tracer indocyanine green (ICG)-Tc-nanocolloid has been introduced for sentinel node imaging. However, until now, a comparison of this tracer with other radiocolloids with a larger particle size has not been effectuated. Based on a head-to-head evaluation in patients with melanoma, we have compared ICG-Tc-nanocolloid (particle size 5-80 nm) with Tc-Senti-Scint (particle size 100-600 nm) to establish differences in drainage pattern and sentinel node localization using lymphoscintigraphy and single-photon emission computed tomography combined with computer tomography (SPECT-CT) in melanoma patients scheduled for sentinel node biopsy.

METHODS

Twenty-five patients (mean age: 56.9 years, range: 25-79 years) with a melanoma scheduled for SLN biopsy prior to (re)excision of the primary lesion (scar) were prospectively included following a two-day procedure. The first day, after Tc-Senti-Scint injection in four intradermal depots around the primary lesion or scar, early/delayed lymphoscintigraphy and SPECT-CT images were acquired. The injection sites were marked. The second day, after assessing lymph node radioactivity using planar scintigraphy, ICG-Tc-nanocolloid was injected at the previously marked skin points and imaging was performed. The paired planar and SPECT-CT images of both tracers were evaluated with respect to drainage patterns, SLN visualization and non-SLN appearing.

RESULTS

Twenty-four out of 25 patients were evaluable. SLN visualization on a patient basis was 100% for ICG-Tc-nanocolloid and 96% for Tc-Senti-Scint, whereas uptake in non-SLNs was found in, respectively, 71% (17/24) and 61% (14/23). Concordance in drainage to 45 lymph node basins was 91%. Discordant drainage was found for two melanomas in the head-and-neck and one in the clavicular area. Unique lymph node basins were seen in 44/45 (98%) for ICG-Tc-nanocolloid and 42/45 (93%) for Tc-Senti-Scint. Concerning identified SLNs, the number was similar for both tracers (n = 58); however, more non-SLNs (65 vs 50) were visualized with ICG-Tc-nanocolloid than with Tc-Senti-Scint.

CONCLUSION

A slightly higher SLN visualization accompanied by a tendency to depict more non-SLNs was found for ICG-Tc-nanocolloid. Excepting the head and neck area, an overall high concordance in drainage was found for both radiotracers. With an additional value for the hybrid tracer due to the combination of preoperative imaging and the additional visual signal in the operation room, added by the fluorescent component of the hybrid tracer, there was a preference for ICG-Tc-nanocolloid.

Roles of Medicinal Plants and Constituents in Gynecological Cancer Therapy: Current Literature and Future Directions

Gynecologic cancers, including cervical, primary peritoneal, ovarian, uterine/endometrial, vaginal and vulvar cancers and gestational trophoblastic disease, are characterized by abnormal cell proliferation in female reproductive cells. Due to the variable pathology of these cancers and the lack of appropriate screening tests in developing countries, cancer diagnosis can be reported in advanced stages in most women and this situation adversely affects prognosis and clinical outcomes of illness. For this reason, many researchers in the field of gynecological oncology have carried out many studies. The treatment of various gynecological problems, which cause physical, biological and psychosocial conditions such as fear, shame, blame and anger, has been important throughout the history. Treatment with herbs has become popular nowadays due to the serious side effects of the synthetic drugs used in treatment and the medical and economical problems caused by them. Many scientists have identified various active drug substances through in vivo and in vitro biological activity studies on medicinal plants from the past to the present. While the intrinsic complexity of natural product-based drug discoveries requires highly integrated interdisciplinary approaches, scientific and technological advances and research trends clearly show that natural products will be among the most important new drug sources in the future. In this review, an overview of the studies conducted for the discovery of multitargeted drug molecules in the rational treatment of gynecological cancers is presented.

Comparison of SPECT-CT with intraoperative mapping in cervical and uterine malignancies

INTRODUCTION

The objective was to evaluate whether hybrid imaging combining single photon emission tomography with computed tomography (SPECT/CT) provides additional clinical value for dectection of sentinel lymph nodes (SLNs) compared with intraoperative combined mapping in uterine and cervical malignancies.

METHODS

This was a retrospective study of prospectively collected data from patients with stages IA-IB2 cervical cancer (International Federation of Gynecology and Obstetrics (FIGO) 2018) or stage I endometrial cancer, who underwent preoperative SPECT/CT for SLN detection. All included patients had dual injection of technetium-99m (^99mTc) with patent blue or indocyanine green.

RESULTS

A total of 171 patients were included with 468 SLNs detected during surgery: 146/171 patients (85.4%) had both radiotracer and blue injection whereas 25/171 patients (14.6%) had radiotracer and indocyanine green injected. The overall detection rate was 95.3%. The detection rate of SLN mapping was 74.9% for SPECT/CT, 90.6% for ^99mTc, 91.8% for blue dye, and 100% for indocyanine green. Bilateral drainage was found in 140 patients (81.9%), detected by ^99mTc in 105 patients (61.4%), by blue in 99 patients (67.3%), by indocyanine green in 23 patients (92%), and by SPECT/CT in 62 patients (36.4%). Atypical SLN locations were identified by SPECT/CT in 64 patients (37.4%), by 99mTc in 28 patients (16.4%), by blue in 17 patients (9.9%), and by indocyanine green in 8 patients (4.7%). Sensitivity and negative predictive value of SLN biopsy to detect lymph node metastasis using dual injection of different intraoperative combined techniques were 88.9% and 97.5%, respectively.

CONCLUSION

SPECT/CT enhanced topographic delineation of SLN and more accurately identified drainage to atypical locations. Fluorescent SLN mapping using indocyanine green offered the highest SLN detection rate. When indocyanine green was used, SPECT/CT did not increase SLN detection, and did not add further information to improve lymph node localization and removal.

The role of computational methods for automating and improving clinical target volume definition

Treatment planning in radiotherapy distinguishes three target volume concepts: the gross tumor volume (GTV), the clinical target volume (CTV), and the planning target volume (PTV). Over time, GTV definition and PTV margins have improved through the development of novel imaging techniques and better image guidance, respectively. CTV definition is sometimes considered the weakest element in the planning process. CTV definition is particularly complex since the extension of microscopic disease cannot be seen using currently available in-vivo imaging techniques. Instead, CTV definition has to incorporate knowledge of the patterns of tumor progression. While CTV delineation has largely been considered the domain of radiation oncologists, this paper, arising from a 2019 ESTRO Physics research workshop, discusses the contributions that medical physics and computer science can make by developing computational methods to support CTV definition. First, we overview the role of image segmentation algorithms, which may in part automate CTV delineation through segmentation of lymph node stations or normal tissues representing anatomical boundaries of microscopic tumor progression. The recent success of deep convolutional neural networks has also enabled learning entire CTV delineations from examples. Second, we discuss the use of mathematical models of tumor progression for CTV definition, using as example the application of glioma growth models to facilitate GTV-to-CTV expansion for glioblastoma that is consistent with neuroanatomy. We further consider statistical machine learning models to quantify lymphatic metastatic progression of tumors, which may eventually improve elective CTV definition. Lastly, we discuss approaches to incorporate uncertainty in CTV definition into treatment plan optimization as well as general limitations of the CTV concept in the case of infiltrating tumors without natural boundaries.

British Gynaecological Cancer Society (BGCS) cervical cancer guidelines: Recommendations for practice

Cervix cancer in many countries is declining and screening programmes and immunisation will reduce the incidence in the next few decades. This guideline attempts to cover management of invasive disease reflecting diagnosis and imaging including new imaging and sentinel lymph node biopsies. Smaller volume disease is usually managed surgically whereas advanced disease is treated with (chemo)- radiation. It also includes discussion of fertility sparing procedures. Practices are changing frequently for all aspects of care usually in attempts to reduce complications and improve quality of life. The management of advanced disease is treated by chemotherapy and the use of newer agents is also discussed. Other sections discuss specialist situations such as cancer in pregnancy, rare cervical tumours, late effects and supportive measures and fertility preserving approaches.

Influence of 99m-Tc-Nanocolloid Activity Concentration on Sentinel Lymph Node Detection in Endometrial Cancer: A Quantitative SPECT/CT Study

This study evaluates quantitative combined single photon emission tomography/computed x-ray tomography (SPECT/CT) to assess the influence of radiotracer concentration on detection of sentinel lymph nodes (SLN) in endometrial cancer (EC). Eighty EC patients underwent pericervical 99m-Tc-nanocolloid injection followed by SPECT/CT. The subgroup of patients with failed SLN detection in SPECT/CT (n = 20) was compared to match-paired patients showing at least two SLNs. Results of intraoperative gamma probe measurements and quantitative SPECT/CT were used for comparison. In patients with detection failure, the percentage of injected dose, absolute activity, and volume of the injection site were significantly lower (30 ± 24% vs. 55 ± 19%; p = 0.01, 43 ± 36 MBq vs. 73 ± 33 MBq; p = 0.04, and 183 ± 164 mL vs. 266 ± 164 mL; p = 0.03) while mean activity concentration in liver, spleen, and bone marrow was significantly higher (p = 0.02). Activity concentration (>33 KBq/mL) and absolute activity (>73 MBq) of injection areas correlated with successful intraoperative SLN detection. In a subgroup of 19 SLNs, a correlation between SPECT/CT-derived uptake and intraoperative count rate was found (R² = 0.8; p < 0.001). SLN detection in EC patients depended on high radiotracer activity at the cervical injection site. Quantitative SPECT/CT could predict successful intraoperative SLN detection and may help to optimize injection technique.

SPECT-CT visualization and biopsy of sentinel lymph nodes in patients with stage IAB-IIA cervical cancer

OBJECTIVE

To evaluate the diagnostic accuracy of sentinel lymph node (SLN) biopsy and to determine clinical significance of preoperative single-photon emission computed tomography/computed tomography (SPECT-CT).

METHODS

We retrospectively evaluate data and images of 55 women with stage IAB-IIA cervical cancer that underwent sentinel lymph node biopsy and subsequent lymph node dissection. ^99mTc-phytate (300 MBq) was injected submucosally in 4 points and SPECT-CT started 2 h after the injection. All lymph nodes (LN) that accumulated radiocolloids were regarded as sentinel. Next day after the mapping radical hysterectomy with complete pelvic and parametrial LN dissection and SLN biopsy were performed according to the institute protocol.

RESULTS

SPECT-CT identified SLNs in 51 of 55 patients. All SLNs were successfully detected during the surgery. The SLN mapping efficacy was 92.7%. LN metastases were diagnosed in 6/51 (11.8%) cases, including 2 patients with positive SLNs. Sensitivity, negative predictive value (NPV) and false-negative rate for SLN biopsy were as follows: 33.4%, 91.8% and 66.6%. In patients with unilateral SPECT-CT localization of SLNs, LN metastases were identified in 4 (20%) of 20 patients but SLN biopsy was false negative in all cases. In 31 women, SPECT-CT detected SLNs on both sides of the pelvis. In this group, regional LN metastases were diagnosed in 2 patients, and in both cases metastases were detected only in SLNs.

CONCLUSIONS

In women with SPECT-CT visualization of SLNs on both sides of the pelvis, SLN biopsy had high sensitivity and NPV. In patients with unilateral SLN localization, SLN biopsy cannot be used for the prediction of regional LN status.

Sentinel lymph node biopsy procedure in squamous vulvar cancer. 10 years follow-up analysis

AIM

Application of sentinel lymph node biopsy (SLNB) procedure in early-stage vulvar cancer and analysis of results, recurrences and complications.

MATERIAL AND METHODS

40 patients with vulvar cancer and SLNB between 2008 and 2018 were retrospectively reviewed. During the surgical procedure the inguinofemoral lymph nodes were checked with a gamma probe to identify the sentinel nodes that were removed and referred for intraoperative pathological assessment. Subsequently, long-term patient follow-up was performed with analysis of complications, relapse and mortality.

RESULTS

40 patients (mean age: 72 years [47-86], the overall detection rate per patient was 95% and a total of 129 Sentinel Lymph Nodes (SLNs) were removed (3.22 SLN/patient). In 3 out of 25 patients with lateral tumour lesions drainage was bilateral and in 2 out of 15 with midline lesions drainage was unilateral. On lymphoscintigraphy, 16 out of 40 had bilateral drainage and 24 unilateral. A total of 119 SLN- and 10 SLN+ were obtained, in 8 out of 10 an inguinofemoral lymphadenectomy was performed. In the SLN- group, one case of lymphatic blockage and one false negative were included. In 12 out of 40 patients there were post-surgical complications, 4 of them lymphoedemas. In the median follow-up (40 months), 6 out of 10 with SLN+ (40% mortality) and 7 out of 30 SLN- (16% mortality) had recurrences.

CONCLUSIONS

SLNB in vulvar cancer is the technique of choice for correct staging and locoregional therapy. Correct clinical lymph node staging is important before surgery in order to avoid potential blockage drainages which could induce a false negative SLN.

Lymphoscintigraphy and sentinel lymph node biopsy in vulvar carcinoma: update from a European expert panel

PURPOSE

This study aimed to update the clinical practice applications and technical procedures of sentinel lymph node (SLN) biopsy in vulvar cancer from European experts.

METHODS

A systematic data search using PubMed/MEDLINE database was performed up to May 29, 2019. Only original studies focused on SLN biopsy in vulvar cancer, published in the English language and with a minimum of nine patients were selected.

RESULTS

Among 280 citations, 65 studies fulfilled the inclusion criteria. On the basis of the published evidences and consensus of European experts, this study provides an updated overview on clinical applications and technical procedures of SLN biopsy in vulvar cancer.

CONCLUSIONS

SLN biopsy is nowadays the standard treatment for well-selected women with clinically negative lymph nodes. Negative SLN is associated with a low groin recurrence rate and a good 5-year disease-specific survival rate. SLN biopsy is the most cost-effective approach than lymphadenectomy in early-stage vulvar cancer. However, future trials should focus on the safe extension of the indication of SLN biopsy in vulvar cancer. Although radiotracers and optical agents are widely used in the clinical routine, there is an increasing interest for hybrid tracers like indocyanine-^99mTc-nanocolloid. Finally, it is essential to standardise the acquisition protocol including SPECT/CT images, and due to the low incidence of this type of malignancy to centralise this procedure in experienced centres for personalised approach.

Fusion of ultrasound and 3D single-photon-emission computed tomography/computed tomography to identify sentinel lymph nodes in vulvar cancer: feasibility study

OBJECTIVE

To evaluate the feasibility of fusion of ultrasound imaging and three-dimensional (3D) single-photon-emission computed tomography/computed tomography (SPECT/CT) in detecting sentinel lymph nodes in women with vulvar cancer.

METHODS

This was a prospective pilot single-center study. Patients with vulvar cancer who were candidates for sentinel lymph-node biopsy were enrolled between December 2018 and February 2019. Fusion imaging virtual navigation using 3D SPECT/CT and ultrasound was performed to investigate the tumor-draining lymph node. All clinical, imaging, surgical and histological information was collected prospectively and entered into a dedicated Excel file. Feasibility and success of fusion imaging virtual navigation and time needed to perform the three steps of fusion imaging were evaluated.

RESULTS

Ten lymph-node sites were evaluated in five consecutive women with a histological diagnosis of vulvar cancer. Fusion imaging virtual navigation was feasible and completed successfully for all (10/10) draining sites. Median overall time to perform fusion imaging was 32 (range, 25-40) min and the time decreased from the first to the last examination.

CONCLUSIONS

The present study demonstrated that fusion imaging virtual navigation using 3D SPECT/CT and ultrasound is feasible and able to detect sentinel lymph nodes in women with vulvar carcinoma. Fusion imaging using ultrasound for detection of sentinel lymph nodes opens up multiple diagnostic and therapeutic opportunities in gynecological oncology. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

In Vivo Stabilized SB3, an Attractive GRPR Antagonist, for Pre- and Intra-Operative Imaging for Prostate Cancer

Purpose

The gastrin-releasing peptide receptor (GRPR), overexpressed on various tumor types, is an attractive target for receptor-mediated imaging and therapy. Another interesting approach would be the use of GRPR radioligands for pre-operative imaging and subsequent radio-guided surgery, with the goal to improve surgical outcome. GRPR radioligands were successfully implemented in clinical studies, especially Sarabesin 3 (SB3) is an appealing GRPR antagonist with high receptor affinity. Gallium-68 labeled SB3 has good in vivo stability, after labeling with Indium-111; however, the molecule shows poor in vivo stability, which negatively impacts tumor-targeting capacity. A novel approach to increase in vivo stability of radiopeptides is by co-administration of the neutral endopeptidase (NEP) inhibitor, phosphoramidon (PA). We studied in vivo stability and biodistribution of [¹¹¹In]SB3 without/with (−/+) PA in mice. Furthermore, SPECT/MRI on a novel, state-of-the-art platform was performed.

Procedures

GRPR affinity of SB3 was determined on PC295 xenograft sections using [¹²⁵I]Tyr⁴-bombesin with tracer only or with increasing concentrations of SB3. For in vivo stability, mice were injected with 200/2000 pmol [¹¹¹In]SB3 −/+ 300 μg PA. Blood was collected and analyzed. Biodistribution and SPECT/MRI studies were performed at 1, 4, and 24 h postinjection (p.i.) of 2.5 MBq/200 pmol or 25 MBq/200 pmol [¹¹¹In]SB3 −/+ 300 μg PA in PC-3-xenografted mice.

Results

SB3 showed high affinity for GRPR (IC₅₀ 3.5 nM). Co-administration of PA resulted in twice higher intact peptide in vivo vs [¹¹¹In]SB3 alone. Biodistribution studies at 1, 4, and 24 h p.i. show higher tumor uptake values with PA co-administration (19.7 ± 3.5 vs 10.2 ± 1.5, 17.6 ± 5.1 vs 8.3 ± 1.1, 6.5 ± 3.3 vs 3.1 ± 1.9 % ID/g tissue (P < 0.0001)). Tumor imaging with SPECT/MRI clearly improved after co-injection of PA.

Conclusions

Co-administration of PA increased in vivo tumor targeting capacity of [¹¹¹In]SB3, making this an attractive combination for GRPR-targeted tumor imaging.

Update on radioguided surgery: from international consensus on sentinel node in head and neck cancer to the advances on gynaecological tumors and localization of non-palpable lesions

The aim of this review is to provide an updated perspective on different fields of radioguided surgery. With reference to the sentinel lymph node biopsy in oral squamous cell carcinoma, we present the results of the interactive debate held at the recent Congress of our specialty about the more relevant aspects of the London Consensus. Drainage peculiarities and indications according to the current guidelines on gynaecological tumours, endometrial and cervical cancer, are detailed and new scenarios for nuclear medicine physicians are presented; robotic surgery and hybrid tracers, for instance. Moreover, the notable growth in radioguided surgery indications for non-palpable lesions, widely used in mammary pathology, make it advisable to update two procedures which have shown satisfying results, such as the solitary pulmonary nodule and the osteoid osteoma.

Present status of sentinel lymph node biopsy in cervical cancer

Cervical cancer is the fourth most common cancer in women, and seventh overall. This disease represents a medical, economic and social burden. In early FIGO stage patients (IA, IB1 and IIA1), nodal involvement is the most important prognostic factor. Imaging evaluation of nodal metastasis is of limited value. In order to determine lymph node involvement, allow loco-regional control of the disease, define the need for adjuvant radiotherapy and improve survival, standard surgery for early disease is radical hysterectomy with systematic pelvic lymphadenectomy. However, this surgical treatment has risks and complications: longer operative time, larger blood loss, neurovascular or ureteral injury, lower-limb lymphedema, symptomatic lymphocysts, hydronephrosis. A method that allows to define the presence of regional metastasis with less morbidity and equal or greater precision is particularly relevant. The use of the sentinel lymph node biopsy is intended to reach that purpose. The present study reviews recent literature on the role of sentinel lymph node biopsy in cervical cancer, analyzing its indications and contraindications, injection and detection techniques, tracers used, surgical and pathological approaches and its applicability in up-to-date clinical practice.

Long-term oncological outcomes of patients with negative sentinel lymph node in vulvar cancer. Comparative study with conventional lymphadenectomy

INTRODUCTION

The aim of this study was to compare oncological outcomes and morbidity in patients with early-stage vulvar cancer with negative sentinel lymph node (SLN) biopsy vs negative inguinofemoral lymphadenectomy (IFL).

MATERIAL AND METHODS

Study with retrospectively collected data in patients with squamous cell vulvar carcinomas ≤ 4 cm without suspected inguinofemoral lymph node metastases. Only patients with negative nodes after histopathology procedure were followed. Patients who underwent only SLN were compared with patients who underwent IFL ± SLN to compare recurrences, survival rates and morbidity.

RESULTS

Ninety-three patients were eligible for follow up: 42 with negative SLN and 51 with negative IFL ± SLN. The median follow-up period was 60.4 months (range 6.7-160.7). The rate of isolated first groin recurrence was 4.8% in patients with negative SLN and 2.0% in patients with negative IFL ± SLN (P = 0.587) and the rates of first isolated local recurrence were 28.6% and 31.4%, respectively (P = 0.823). Only 1 patient (2.4%) in the group of negative SLN had distant recurrence. The disease-specific survival rate at 5 years was 83.3% in the negative SLN group and 92.2% in the negative IFL ± SLN group (P = 0.214). We observed a higher rate of wound breakdown and infection after IFL than SLN biopsy (17.6% vs 10.6%; P = 0.020) and lymphedema (33.3% vs 0%; P < 0.001).

CONCLUSIONS

We report in the same population of patients with early-stage vulvar cancer that SLN biopsy does not have significantly higher rates of groin recurrences or lower survival rates compared with IFL. Moreover, the SLN procedure has less morbidity, which should encourage gynecologists to abandon IFL.

99mTc-labeled sodium phytate and stannous chloride injection accurately detects sentinel lymph node in axillary of early stage breast cancer: a randomized, controlled study

Aim

The aim of this study was to assess the sentinel lymph node (SLN) detection rate and accuracy of ^99mTc-labeled sodium phytate and stannous chloride (^99mTc-PHY) injection versus ^99mTc-labeled sulfur colloid (^99mTc-SC) injection in sentinel lymph node biopsy (SLNB) in patients with early stage breast cancer.

Methods

A total of 146 consecutive female patients with early stage breast cancer were recruited in this open-labeled, randomized, controlled study. SLNB was conducted on all patients, and ^99mTc-PHY or ^99mTc-SC was used as the radioactive agent (RA). Axillary lymph node dissections were performed in all patients post SLN dissections.

Results

The detection rate of ^99mTc-PHY group was higher compared with that of ^99mTc-SC group (p=0.023), but no difference in the detection rate by dye alone (p=0.190) or by RAs alone (p=0.615) was found between the two groups, and the number of identified SLNs (p=0.100), number of identified SLNs by dye alone (p=0.161), and number of identified SLNs by RA alone (p=0.242) were similar between the two groups. In addition, the sensitivity, specificity, false-negative rate, false-positive rate, and accuracy rate of SLNB showed no difference between ^99mTc-PHY and ^99mTc-SC groups (sensitivity: p=0.645; specificity: p=0.511; false-negative rate: p=0.645; false-positive rate: p=0.511; accuracy rate: p=0.464).

Conclusion

Our study revealed that ^99mTc-PHY was qualified to be a convincing radiopharmaceutical in SLNB.

Role of ICG-99mTc-nanocolloid for sentinel lymph node detection in cervical cancer: a pilot study

PURPOSE

Sentinel lymph node biopsy (SLNB) can be used for nodal staging in early cervical cancer. For this purpose, the tracers most commonly used are radiotracers based on technetium. For the last decade, indocyanine green (ICG) has been used as a tracer for SLNB in other malignancies with excellent results and, more recently, a combination of ICG and a radiotracer has been shown to have the advantages of both tracers. The aim of this study was to evaluate the role of ICG-^99mTc-nanocolloid in SLN detection in patients with cervical cancer.

METHODS

This prospective study included 16 patients with cervical cancer. The hybrid tracer was injected the day (19-21 h) before surgery for planar and SPECT/CT lymphoscintigraphy. Blue dye was administered periorificially in 14 patients. SLNs were removed according to their distribution on lymphoscintigraphy and when radioactive, fluorescent and/or stained with blue dye. Nodal specimens were pathologically analysed for metastases including by immunochemistry.

RESULTS

Lymphoscintigraphy and SPECT/CT showed drainage in all patients. A total of 69 SLNs were removed, of which 66 were detected by their radioactivity signal and 67 by their fluorescence signal. Blue dye identified only 35 SLNs in 12 of the 14 patients (85.7%). All patients showed bilateral pelvic drainage. Micrometastases were diagnosed in two patients, and were the only lymphatic nodes involved.

CONCLUSIONS

SLNB with ICG-^99mTc-nanocolloid is feasible and safe in patients with early cervical cancer. This hybrid tracer provided bilateral SLN detection in all patients and a higher detection rate than blue dye, so it could become an alternative to the combined technique.

Radioguided surgery and the GOSTT concept: From pre-operative image and intraoperative navigation to image-assisted excision

Radio-guided surgery has been developed for application in those disease scheduled for surgical management, particularly in areas of complex anatomy. This is based on the use of pre-operative scintigraphic planar, tomographic and fused SPECT/CT images, and the possibility of 3D reconstruction for the subsequent intraoperative locating of active lesions using handheld devices (detection probes, gamma cameras, etc.). New tracers and technologies have also been incorporated into these surgical procedures. The combination of visual and acoustic signals during the intraoperative procedure has become possible with new portable imaging modalities. In daily practice, the images offered by these techniques and devices combine perioperative nuclear medicine imaging with the superior resolution of additional optical guidance in the operating room. In many ways they provide real-time images, allowing accurate guidance during surgery, a reduction in the time required for tissue location and an anatomical environment for surgical recognition. All these approaches have been included in the concept known as (radio) Guided intraOperative Scintigraphic Tumour Targeting (GOSTT). This article offers a general view of different nuclear medicine and allied technologies used for several GOSTT procedures, and illustrates the crossing of technological frontiers in radio-guided surgery.

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

Background

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

Methods

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

Results

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

Conclusion

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

Fusion of freehand SPECT and ultrasound: First experience in preoperative localization of sentinel lymph nodes

PURPOSE

Radioguided sentinel lymph node biopsy (SLNB) is the standard of care in breast cancer and melanoma. Additional preoperative Single-photon emission computed tomography (SPECT/CT) for improved anatomical co-registration of the SLNs causes additional radiation exposure and is time-consuming and expensive. The aim of this prospective study was to evaluate a novel approach involving real-time fusion of freehand SPECT (fhSPECT) and ultrasound (US) for anatomical co-registration of SLNs.

METHODS

From February 2015 to February 2016, 153 patients were included in this prospective study. All patients underwent lymphoscintigraphy according to practical guidelines and 151 (118 cases of breast cancer, 30 cutaneous malignancies, and three cases of vulvar cancer) of the 153 patients were additionally investigated with fhSPECT-US. FhSPECT connected to a hand-held gamma detector generates three-dimensional images of the radioactivity distribution in the scanned area. For co-registration and real-time fusion of fhSPECT and subsequently performed US, an infrared stereo tracking system was used.

RESULTS

In all patients an SLN was found on lymphoscintigraphy, and the fhSPECT detected corresponding hotspots in all but one patient. In 72 % of patients and 73 % of lymph node basins, real-time anatomical co-registration with US was feasible. The rate of success in achieving good co-registration increased from 60 to 75 % after training by a radiologist specialized in breast imaging. A higher co-registration rate (78 %) was observed in patients with only one SLN than in those with two SLNs (68 %) or three or more SLNs (0 %).

CONCLUSIONS

Real-time fusion of fhSPECT and US for preoperative anatomical co-registration of SLNs is feasible. However, before this approach can completely replace preoperative lymphatic imaging, further technical developments are needed.

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.

3D scintigraphic imaging and navigation in radioguided surgery: freehand SPECT technology and its clinical applications

Freehand SPECT (fhSPECT) is a technology platform for providing 3-dimensional (3D) navigation for radioguided surgical procedures, such as sentinel lymph node (SLN) biopsy (SLNB). In addition to the information provided by conventional handheld gamma detection probes, fhSPECT allows for direct visualization of the distribution of radioactivity in any given region of interest, allowing for improved navigation to radioactive target lesions and providing accurate lesion depth measurements. Herein, we will review the currently available clinical data on the use of fhSPECT: (i) for SLNB of various malignancies, including difficult-to-detect SLNs, and (ii) for radioguided localization of solid tumors. Moreover, the combination of fhSPECT with other technologies (e.g., small field-of-view gamma cameras, and diagnostic ultrasound) is discussed. These technical advances have the potential to greatly expand the clinical application of radioguided surgery in the future.

The use of SPECT/CT for anatomical mapping of lymphatic drainage in vulvar cancer: possible implications for the extent of inguinal lymph node dissection

PURPOSE

To determine the lymphatic drainage pattern using SPECT/CT in clinically node-negative (cN0) patients with vulvar cancer, and to evaluate the possible implications for the extent of inguinal lymph node dissection.

METHODS

A total of 83 patients with vulvar cancer scheduled for sentinel node (SN) biopsy were injected peritumorally with radioactive nanocolloid particles followed by lymphoscintigraphy and SPECT/CT for anatomical localization. The SN and higher-echelon nodes on SPECT/CT were located in different zones in the groin and pelvic region. The groin was divided into five zones according to Daseler et al.: four zones obtained by drawing two perpendicular lines over the saphenofemoral junction and one zone directly overlying this junction. The nodes in the pelvic region were classified into three zones: external iliac/obturator, the common iliac and the paraaortic zones.

RESULTS

A total of 217 SNs and 202 higher-echelon nodes were localized on SPECT/CT. All SNs were located in the five zones according to Daseler et al.: 149 (69%) in the medial superior region, 31 (14%) in the medial inferior region, 22 (10%) in the central region, 14 (6.5%) in the lateral superior region and only 1 (0.5%) in the lateral inferior region. The higher-echelon nodes were located both in the groin (15%) and in the pelvic region (85%).

CONCLUSION

In patients with cN0 vulvar cancer, lymphatic drainage occurs predominantly to the medial regions of the groin. Drainage to the lateral inferior region of the groin is only incidental and in SN-positive patients this zone might be spared in subsequent extended lymph node dissection. This may lead to a decrease in the morbidity associated with this procedure. SPECT/CT is able to personalize lymphatic mapping, providing detailed information about the number and anatomical location of SNs for adequate surgical planning in the groin.

EANM practice guidelines for lymphoscintigraphy and sentinel lymph node biopsy in melanoma

PURPOSE

Sentinel lymph node biopsy is an essential staging tool in patients with clinically localized melanoma. The harvesting of a sentinel lymph node entails a sequence of procedures with participation of specialists in nuclear medicine, radiology, surgery and pathology. The aim of this document is to provide guidelines for nuclear medicine physicians performing lymphoscintigraphy for sentinel lymph node detection in patients with melanoma.

METHODS

These practice guidelines were written and have been approved by the European Association of Nuclear Medicine (EANM) to promote high-quality lymphoscintigraphy. The final result has been discussed by distinguished experts from the EANM Oncology Committee, national nuclear medicine societies, the European Society of Surgical Oncology (ESSO) and the European Association for Research and Treatment of Cancer (EORTC) melanoma group. The document has been endorsed by the Society of Nuclear Medicine and Molecular Imaging (SNMMI).

CONCLUSION

The present practice guidelines will help nuclear medicine practitioners play their essential role in providing high-quality lymphatic mapping for the care of melanoma patients.