Steerable DROP-IN radioguidance during minimal-invasive non-robotic cervical and endometrial sentinel lymph node surgery.

PURPOSE: The recently introduced tethered DROP-IN gamma probe has revolutionized the way robotic radioguided surgery is performed, fully exploiting the nature of steerable robotic instruments. Given this success, the current first-in-human study investigates if the DROP-IN can also provide benefit in combination with steerable non-robotic instruments during conventional laparoscopic surgery, showing equivalence or even benefit over a traditional rigid gamma probe. METHODS: The evaluation was performed in ten patients during laparoscopic cervical (n = 4) and endometrial (n = 6) cancer sentinel lymph node (SLN) procedures. Surgical guidance was provided using the hybrid, or bi-modal, SLN tracer ICG-99mTc-nanocolloid. SLN detection was compared between the traditional rigid laparoscopic gamma probe, the combination of a DROP-IN gamma probe and a steerable laparoscopic instrument (LaproFlex), and fluorescence imaging. RESULTS: The gynecologists experienced an enlarged freedom of movement when using the DROP-IN + LaproFlex combination compared to the rigid laparoscopic probe, making it possible to better isolate the SLN signal from background signals. This did not translate into a change in the SLN find rate yet. In both cervical and endometrial cancer combined, the rigid probe and DROP-IN + LaproFlex combination provided an equivalent detection rate of 96%, while fluorescence provided 85%. CONCLUSION: We have successfully demonstrated the in-human use of steerable DROP-IN radioguidance during laparoscopic cervical and endometrial cancer SLN procedures, expanding the utility beyond robotic procedures. Indicating an improved surgical experience, these findings encourage further investigation and consideration on a path towards routine clinical practice and improved patient outcome. TRIAL REGISTRATION: HCB/2021/0777 and NCT04492995; https://clinicaltrials.gov/study/NCT04492995.

Comparison of [18F]fluorocholine PET/CT with [99mTc]sestamibi and ultrasonography to detect parathyroid lesions in primary hyperparathyroidism: a prospective study.

Background: Primary hyperparathyroidism is a common endocrine disorder produced by the increase of parathyroid hormone (PTH) due to a benign adenoma of a single parathyroid gland, or as multiple gland hyperplasia, or as a rare malignant tumor. Preoperative imaging scans are frequently necessary for the minimally invasive parathyroidectomies to identify the location of enlarged parathyroid glands and to design the procedure. Methods: The diagnostic reliability of [18F]fluorocholine positron emission tomography/computed tomography (FCH PET/CT), [99mTc]sestamibi [multiplexed ion beam imaging (MIBI)] and cervical ultrasonography was analyzed in 37 patients diagnosed with primary hyperparathyroidism undergoing minimally invasive parathyroidectomy. The three preoperative imaging techniques were correlated with intraoperative and histopathological findings as well as changes in biochemical parameters (serum PTH and calcium levels). Statistical analysis was carried out with SPSS version 24.0. Results: In 30 of 37 patients (81.1%), FCH PET/CT correctly localized the pathological gland. In 3 cases of ectopic adenomas, the accuracy of the techniques was 100% (3/3) for FCH PET/CT, 66.7% (2/3) for MIBI, and 33.3% (1/3) for neck ultrasonography. Neither neck ultrasonography nor MIBI were able to locate pathological parathyroid glands in those patients with multiglandular disease, while FCH PET/CT correctly located one patient (1/3, 33.3%) with two adenomas and 3 patients (3/6, 50.0%) with hyperplasia. The three imaging techniques, FCH PET/CT, MIBI and neck ultrasound yielded a sensitivity of 92.1%, 57.9% and 32.4%, a positive predictive value of 94.6%, 84.6% and 78.6%, and a diagnostic accuracy of 96.4%, 85.7% and 79.0%, respectively. Conclusions: In this group of patients diagnosed with primary hyperparathyroidism, FCH PET/CT was superior to MIBI and neck ultrasound in detecting adenomas, particularly in the presence of ectopic glands or multiglandular disease.

Preoperative localization of lung nodules: a comparative analysis of hookwire and radio-guided procedures.

Background: Histological diagnosis of pulmonary nodules requires surgical resection on many occasions. There are multiple localization strategies each with their own benefits and complications. The objective of this study is to compare preoperative lung nodule localization with hookwire and radiotracer injection (radioguided occult lesion localization, ROLL). To compare results, complications, and volume of the sample resected with both techniques. Methods: Patients undergoing resection of pulmonary nodules with video-assisted thoracoscopy and pre-surgical localization with hookwire or ROLL were studied. Eighty-eight pulmonary nodules were resected in 76 patients: 52 with a hook wire and 36 with a radiotracer. The localization rate, the shortest distance between the nodule and the pleura, the intrapulmonary distance of the locator, the complications, the volume of the resection piece, and the histological result were all assessed. In addition, the factors that influence the volume of the surgical piece were analyzed. Results: All the nodules were resected with both techniques. The intrapulmonary path of the locator is longer for the ROLL group (23.91 vs. 16.28 mm; P=0.04), with no differences in the distance from the nodule to the pleura. The rate of pneumothorax was significantly higher after the placement of a hook wire (69.2% vs. 24.2%; P<0.0001), while there were no differences in the presence of hemorrhage. The volume of the pieces resected using ROLL was more minor than with hookwire, although not statistically significant (20.19 vs. 34.26 cc; P=0.07). Conclusions: Preoperative localization with the ROLL technique is safer than the placement of hookwire. In addition, the ROLL technique shows a tendency to obtain a smaller volume of resected tissue since the marking is not affected by the intrapulmonary route used during marker placement. ROLL technique allows to locate lung nodules with fewer complications than hookwire and probably gets smaller resection samples.

Evaluation of patients with advanced epithelial ovarian cancer before primary treatment: correlation between tumour burden assessed by [18F]FDG PET/CT volumetric parameters and tumour markers HE4 and CA125.

OBJECTIVES: Accurate assessment of disease extent is required to select the best primary treatment for advanced epithelial ovarian cancer patients. Estimation of tumour burden is challenging and it is usually performed by means of a surgical procedure. Imaging techniques and tumour markers can help to estimate tumour burden non-invasively. 2-[18F]FDG PET/CT allows the evaluation of the whole-body disease. This study aimed to correlate HE4 and CA125 serum concentrations with tumour burden evaluated by volumetric 2-[18F]FDG PET/CT parameters in advanced high-grade epithelial ovarian cancer. METHODS: We included 66 patients who underwent 2-[18F]FDG PET/CT and serum tumour markers determination before primary treatment. Volumes of interest were delimited in every pathological uptake. Whole-body metabolic tumour volume (wb_MTV) and total lesion glycolysis (wb_TLG) were calculated summing up every VOI's MTV value. SUVmax thresholds were set at 40% (MTV40 and TLG40) and 50% (MTV50 and TLG50). In addition, four VOI subgroups were defined: peritoneal carcinomatosis, retroperitoneal nodes, supradiaphragmatic nodes, and distant metastases. MTV and TLG were calculated for each group by adding up the corresponding MTV values. TLG was calculated likewise. RESULTS: wb_MTV and wb_TLG were found to be significantly correlated with serum CA125 and HE4 concentrations. The strongest correlation was observed between HE4 and wb_MTV40 (r = 0.62, p < 0.001). Pearson's correlation coefficients between peritoneal carcinomatosis MTV40 and tumour markers were 0.61 (p < 0.0001) and 0.29 (p = 0.02) for HE4 and CA125 respectively. None of these tumour markers showed a positive correlation with tumour load outside the abdominal cavity assessed by volumetric parameters. CONCLUSION: HE4 performs better than CA125 to predict metabolic tumour burden in high-grade epithelial ovarian cancer before primary treatment. 2-[18F]FDG PET/CT volumetric parameters arise as feasible tools for the objective assessment of tumour load and its anatomical distribution. These results support the usefulness of HE4 and PET/CT to improve the stratification of these patients in clinical practice. KEY POINTS: • In patients with high-grade advanced ovarian epithelial carcinoma, both CA125 and HE4 correlate to whole-body tumour burden assessed by PET/CT before primary treatment. • HE4 estimates peritoneal disease much better than CA125. • PET/CT volumetric parameters arise as feasible tools for the objective assessment of tumour load and its anatomical distribution.

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.

Role of a portable gamma-camera with optical view for margins assessment of pulmonary nodules resected by radioguided surgery.

PURPOSE: Radioguided occult lesion localization (ROLL) of pulmonary nodules is an alternative to hook-wire. Both required of a histological margin assessment. The activity emerging from the radiotracer allows to obtain an intraoperative scintigraphic image of the surgical specimen by a portable gamma-camera (PGC) fitted with an optical view, which provides information about the localization of the nodule in relation to the margins. The aim of this study was to evaluate the intraoperative use of a PGC for margin assessment of pulmonary nodules. METHODS: ROLL technique was used in 38 nodules (36 pulmonary, 1 chest wall, and 1 pleural nodules). A PGC intraoperative image of the surgical specimen was obtained in 32. Scintigraphic results were compared to the histological assessment. Other factors, such as nodule size, distance from the pleural surface, or distance covered by the needle, were considered as possible factors for non-centered lesions. RESULTS: PGC images showed that the lesion was in contact with the margins in 8/32 cases and centered in 24. In all cases in which the lesion was considered as centered by the PGC, the margins were free of involvement (NPV 100%), although the PPV is low. CONCLUSIONS: The use of a PGC for margin assessment after pulmonary nodule resection is feasible and provides a high NPV in our series. In addition, the short intraoperative time required for its use makes the PGC a useful tool for providing supplementary information to histopathologic results. Further studies from different surgical teams are required for an external validation.

Paraaortic sentinel lymph node detection in intermediate and high-risk endometrial cancer by transvaginal ultrasound-guided myometrial injection of radiotracer (TUMIR).

OBJECTIVE: We aimed to evaluate the accuracy of sentinel lymph node (SLN) mapping with transvaginal ultrasound-guided myometrial injection of radiotracer (TUMIR) to detect lymph node (LN) metastases, in patients with intermediate and high-risk endometrial cancer (EC), focusing on its performance to detect paraaortic involvement. METHODS: Prospective study including women with preoperative intermediate or high-risk EC, according to ESMO-ESGO-ESTRO consensus, who underwent SLN mapping using the TUMIR approach. SLNs were preoperatively localized by planar and single photon emission computed tomography/computed tomography images, and intraoperatively by gamma-probe. Immediately after SLN excision, all women underwent systematic pelvic and paraaortic lymphadenectomy by laparoscopy. RESULTS: The study included 102 patients. The intraoperative SLN detection rate was 79.4% (81/102). Pelvic and paraaortic drainage was observed in 92.6% (75/81) and 45.7% (37/81) women, respectively, being exclusively paraaortic in 7.4% (6/81). After systematic lymphadenectomy, LN metastases were identified in 19.6% (20/102) patients, with 45.0% (9/20) showing paraaortic involvement, which was exclusive in 15.0% (3/20). The overall sensitivity and negative predictive value (NPV) of SLNs by the TUMIR approach to detect lymphatic involvement were 87.5% and 97.0%, respectively; and 83.3% and 96.9%, for paraaortic metastases. After applying the MSKCC SLN mapping algorithm, the sensitivity and NPV were 93.8% and 98.5%, respectively. CONCLUSION: The TUMIR method provides valuable information of endometrial drainage in patients at higher risk of paraaortic LN involvement. The TUMIR approach showed a detection rate of paraaortic SLNs greater than 45% and a high sensitivity and NPV for paraaortic metastases in women with intermediate and high-risk EC.

COVID-19 en la biopsia selectiva de ganglio centinela: el invitado inesperado / COVID-19 on selective sentinel node biopsy: the unexpected guest

OBJETIVO: Describir las medidas adoptadas dentro del plan de contingencia del COVID-19 respecto a la biopsia selectiva de ganglio centinela (BSGC) y analizar su impacto sobre la actividad asistencial. METODOLOGÍA: Estudio cualitativo, descriptivo y retrospectivo de BSGC realizadas durante el período del 14/03 al 11/05 de 2020. Análisis de las medidas tomadas para minimizar las probabilidades de contagio y resultados de PCR de pacientes y personal. Comparativa de casos con los realizados en el mismo período de 2019. Actividad diaria de linfogammagrafía y de cirugía radioguiada (CRG) por indicación médica. Cálculo numérico y porcentual de CRG por hospital y recursos humanos diarios de medicina nuclear requeridos. RESULTADOS: Se realizaron 42 intervenciones con BSGC, un 31,1% menos que en 2019. La indicación médica de cáncer de mama experimentó el mayor descenso de actividad (n=18, 41,9%). Del total de CRG, Hospital Clínic realizó el 45,2%, Hospital Maternitat el 31,0%, Hospital Plató el 16,7% y Hospital Sant Joan de Déu el 7,1% restante. En relación con los recursos humanos, la planificación inicial se cumplió en un 77% de los días. El total de los controles PCR a pacientes (n=42) y personal de CRG (n=9) dio resultado negativo. CONCLUSIONES: El COVID-19 influyó negativamente en la actividad asistencial de la BSGC del Hospital Clínic, pero fue compensado por una planificación acertada, basada en el análisis previo de los procesos del procedimiento, que permitió adaptar los recursos de material y personal a las circunstancias cambiantes, otorgándole una flexibilidad que posibilitó el cumplimiento de la programación establecida

OBJECTIVE: To describe the measures taken within the COVID-19 contingency plan concerning sentinel lymph node biopsy (SNB) procedures and to assess their impact on healthcare activity. METHODOLOGY: Qualitative, descriptive and retrospective study of SNB procedures conducted during the lockdown period of COVID-19 (14/03 to 11/05 2020). Analysis of measures taken to minimise the chances of contagion and PCR outcomes of patients and staff. Comparison with SNB procedures conducted in the same time interval in 2019. Daily activity of lymphoscintigraphy and radioguided surgery (RGS) by medical indication. Numerical and percentage calculation of RGS by hospital and daily requirements for human resources in nuclear medicine. RESULTS: Forty-two SNB were performed, representing 31.1% less than those conducted in the same period in 2019. The medical indication of breast cancer showed the greatest activity decrease (n=18, 41.9%). RGS was performed in 45.2% of patients in Hospital Clínic, 31.0% in Maternitat, 16.7% in Plató and 7.1% in Sant Joan de Déu Hospital. Concerning the human resources required, the initial planning was accomplished in 77% of the days (24/31). All the PCR samples from patients (n=42) and RGS staff (n=9) were negative for COVID-19. CONCLUSIONS: COVID-19 negatively influenced the healthcare activity of SNB in Hospital Clínic, but was compensated by adequate planning, based on prior analysis of the procedure's processes, which allowed adaptation of material and personnel resources to the changing circumstances. This allowed flexibility, which in turn enabled compliance with the established schedule

Comparison of 99mTc-Tilmanocept and Hybrid Indocyanine Green-99mTc-Albumin Nanocolloid Drainage in a Patient With Melanoma in the Scalp.

We present the planar lymphoscintigraphies and SPECT/CT images of a 60-year-old man diagnosed as having melanoma (Breslow 1.8 mm) in left parietal scalp, close to head midline. Sentinel lymph node biopsy using Tc-tilmanocept was performed, but the surgery was canceled. Two weeks later, sentinel lymph node biopsy was repeated, but using the hybrid radiotracer indocyanine green-Tc-albumin nanocolloid. The lymphatic drainage in left laterocervical region was similar with these 2 radiotracers, but on the right side, more sentinel lymph nodes were detected with nanocolloid compared with tilmanocept.

PET/CT Integrated With CT Colonography in Preoperative Obstructive Colorectal Cancer by Incomplete Optical Colonoscopy: A Prospective Study.

AIM: The aim of this study was to evaluate if integrating whole-body PET/CT with CT colonography (PET/CTC) improves the preoperative diagnosis of obstructive colorectal cancer (CRC). METHODS: We prospectively included 47 consecutive patients (18 women and 29 men; mean age, 71 ± 14 years) suspected of having CRC by optical colonoscopy, which was not completed due to obstructive masses. To perform PET/CTC, a small caliber Foley catheter was inserted to distend the colon with CO2 insufflations. Polyps measuring 10 mm or larger were considered as high risk of malignancy. All findings were histologically confirmed. RESULTS: Colorectal cancer was localized in the sigmoid (n = 21), rectum (n = 7), rectosigmoid junction (n = 5), ascending (n = 7), descending (n = 5), and transverse (n = 2) colon. All tumors showed FDG uptake (mean ± SD SUVmax, 20.02 ± 9.9) including one synchronic tumor (SUVmax, 10.46). Forty-seven polyps were histologically confirmed as smaller than 10 mm (n = 35) and 10 mm or larger (n = 12). All 12 polyps 10 mm or larger showed FDG uptake (SUVmax range, 3.08-19.5), but only one smaller than 10 mm could be identified by PET. Pathological lymph nodes were diagnosed in 17/47 cases after surgical removal with a sensitivity and specificity for CTC and PET/CTC of 71% and 97% and 59% and 100%, respectively. Liver metastases were confirmed in 9 patients and in 4/9 along with lung metastases (n = 2) or implants (n = 2), showing a sensitivity and specificity for CTC of 89% and 100% and both 100% for PET/CTC. CONCLUSIONS: PET/CTC is a reliable technique for staging CRC and diagnosing synchronous tumors. In this series, PET/CTC was not able to identify small polyps but showed potential use for ruling out 10 mm or larger polyps at high risk of malignancy.

Assessment of Response to Neoadjuvant Chemoradiotherapy by 18F-FDG PET/CT in Patients With Locally Advanced Esophagogastric Junction Adenocarcinoma.

PURPOSE: The outcome of locally advanced adenocarcinoma of the esophagogastric junction (AEG) treated with preoperative chemoradiotherapy is heterogeneous, and favorable response to this treatment is a key factor in the patient's prognosis. The aim of this study was to evaluate F-FDG PET/CT in assessing metabolic response in patients with AEG. MATERIALS AND METHODS: This prospective study evaluated all consecutive patients with potentially operable locally advanced AEG who were candidates for neoadjuvant chemoradiotherapy. PET/CT and contrast-enhanced thoracoabdominal CT were performed at baseline and 2 weeks after completion of chemoradiotherapy for response evaluation. The response rate was assessed using Response Evaluation Criteria in Solid Tumors criteria for contrast-enhanced thoracoabdominal CT and Positron Emission Tomography Response Criteria in Solid Tumors criteria for PET/CT. The regression rate was assessed using a 5-grade histopathology scoring system of the surgically resected tumor. Metastatic lesions were confirmed by histopathology examination or imaging and clinical follow-up at 6 months. RESULTS: A total of 40 cases were finally included in the study. Distant metastases were found in the baseline PET/CT in 6 of 40 cases (retroperitoneal [2] or mediastinal/hiliar [1] lymph nodes and liver [2] or bone [1] metastases) and were therefore excluded from surgery. Pathologic response correlated with the ΛSUVmax threshold of ≤45% (P = 0.033). CT response correlated well with both the baseline SUVmax (P = 0.039) and the ΛSUVmax (P = 0.001). Five-year survival curves for AEG correlated with the ΛSUVmax using a threshold of ≤45% for both progression-free and overall survival. CONCLUSIONS: F-FDG PET/CT is useful for diagnosing nonsuspected metastasis before neoadjuvancy in potentially operable AEG. The ΛSUV correlates with pathologic response and is a long-term independent prognostic factor of survival.

PISCOM: a new procedure for epilepsy combining ictal SPECT and interictal PET.

PURPOSE: We present a modified version of the SISCOM procedure that uses interictal PET instead of interictal SPECT for seizure onset zone localization. We called this new nuclear imaging processing technique PISCOM (PET interictal subtracted ictal SPECT coregistered with MRI). METHODS: We retrospectively studied 23 patients (age range 4-61 years) with medically refractory epilepsy who had undergone MRI, ictal SPECT, interictal SPECT and interictal FDG PET and who had been seizure-free for at least 2 years after surgical treatment. FDG PET images were reprocessed (rFDG PET) to assimilate SPECT features for image subtraction. Interictal SPECT and rFDG PET were compared using statistical parametric mapping (SPM). PISCOM and SISCOM images were evaluated visually and using an automated volume of interest-based analysis. The results of the two studies were compared with each other and with the known surgical resection site. RESULTS: SPM showed no significant differences in cortical activity between SPECT and rFDG PET images. PISCOM and SISCOM showed equivalent results in 17 of 23 patients (74%). The seizure onset zone was successfully identified in 19 patients (83%) by PISCOM and in 17 (74%) by SISCOM: in 15 patients (65%) the two techniques showed concordant successful results. The volume of interest-based analysis showed no significant differences between PISCOM and SISCOM in identifying the extension of the seizure onset zone. However, PISCOM showed a lower amount of indeterminate activity due to propagation, background or artefacts. CONCLUSION: Preliminary findings of this initial proof-of-concept study suggest that perfusion and glucose metabolism in the cerebral cortex can be correlated and that PISCOM may be a valid technique for identification of the seizure onset zone. However, further studies are needed to validate these results.