Technetium-99m Sulfur Colloid Research Articles

Mapping Colorectal Distribution of Cell-free and Cell-associated HIV Surrogates Following Simulated Anal Intercourse to Aid Rectal Microbicide Development.

Anal sex remains the greatest HIV transmission risk for men who have sex with men and carries substantial population attributable risk among women. Despite a growing array of HIV pre-exposure prophylaxis (PrEP) options, rectal microbicides remain desirable as on demand, non-systemic PrEP. Rectal microbicide product development for PrEP requires understanding the spatiotemporal distribution of HIV infectious elements in the rectosigmoid to optimize formulation development. Outpatient setting with healthy research participants. Six healthy men underwent simulated receptive anal sex with an artificial phallus fitted with a triple lumen catheter in the urethral position. To simulate ejaculation of HIV-infected semen, autologous seminal plasma laden with autologous blood lymphocytes from apheresis labeled with 111Indium-oxine (cell-associated) and 99mTechnetium-sulfur colloid (cell-free) as HIV surrogates were injected into the rectal lumen through the phallic urethra. Spatiotemporal distribution of each radioisotope was assessed using SPECT/CT over eight hours. Analysis of radiolabel distribution used a flexible principal curve algorithm to quantitatively estimate rectal lumen distribution. Cell-free and cell-associated HIV surrogates distributed to a maximal distance of 15 and 16 cm, respectively, from the anorectal junction (∼19 and ∼20 cm from the anal verge), with a maximal signal intensity located 6 and 7 cm, respectively. There were no significant differences in any distribution parameters between cell-free and cell-associated HIV surrogate. Cell-free and cell-associated HIV surrogate distribution in the rectosigmoid can be quantified with spatiotemporal pharmacokinetic methods. These results describe the ideal luminal target distribution to guide rectal microbicide development.

How much time is enough? Sentinel lymph node mapping time depends on the radiotracer agent.

In 2014, technetium-99m tilmanocept (TcTM) replaced technetium-99m sulfur colloid (TcSC) as the standard lymphoscintigraphy (LS) mapping agent in melanoma patients undergoing sentinel lymph node biopsy (SLNB). The aim of this study was to examine differences in mapping time, intra-operative identification of sentinel lymph node (SLN), and false negative rate (FNR) between patients who underwent SLNB with TcTM compared to TcSC. Patients who underwent SLNB between 2010 and 2018 were retrospectively identified. Patient demographic, tumor, and imaging data was stratified by receipt of TcSC (n = 258) or TcTM (n = 133). Student's t test and χ2 test were used to compare characteristics and outcomes. Both cohorts were similar in demographic, primary tumor characteristics, and total number of SLN identified (TcTM 3.56 vs. TcSC 3.28, p = 0.244). TcTM was associated with significantly shorter LS mapping times (51.8 vs. 195.1 min, p < 0.01). There was no significant difference in the number of patients with positive SLN (TcTM 11.3 vs. TcSC 17.4%, p = 0.109) and the FNR was similar between both groups (TcTM 25% vs. TcSC 22%). TcTM was associated with significantly shorter LS mapping time while identifying similar numbers of SLN. Our results support further study to ensure similar FNR and oncologic outcomes between agents.

Sentinel lymph node detection differs when comparing lymphoscintigraphy to lymphography using water soluble iodinated contrast medium and digital radiography in dogs.

Sentinel lymph node (SLN) mapping by various means has become standard of care in certain types of human cancers and is receiving more attention in veterinary oncology. Current SLN mapping techniques can be costly and often require advanced imaging equipment. The objective of this prospective, method comparison study was to compare an SLN mapping protocol of lymphoscintigraphy to lymphography using water soluble iodinated contrast medium (WIC) and digital radiography for identification of an SLN. Lymphoscintigraphy and lymphography were performed on eight healthy purpose-bred dogs using technetium-99m sulfur colloid and WIC injected into the subcutaneous tissues in a four-quadrant technique around a predefined area of skin on the brachium. Images were obtained using a gamma camera and digital radiography at different time points post-injection. Image sequences were evaluated by one of two American College of Veterinary Radiology board-certified veterinary radiologists. Data obtained were compared between methods using descriptive statistics. An SLN was identified in all dogs with lymphoscintigraphy and seven of eight dogs with lymphography. Agreement between results of the lymphoscintigraphy and lymphography studies was a complete match in three dogs, a partial match in four dogs, and no match in one dog. The SLN detected differed based on the imaging modality used.

Nonliposuction Endoscopic Sentinel Lymph Node Biopsy Through the Periareolar Incision.

Background. Sentinel lymph node biopsy (SLNB) has been an alternative to axillary lymph node dissection as a standard procedure for breast cancer patients with clinically negative lymph nodes. Endoscopic technique has been developed for over 20years but remains to be mastered by a slice of surgeons. Suction and squeezing in the liposuction endoscopic procedures may increase risk of local recurrence and metastasis. In this study, we present our method of SLNB procedure through the periareolar incision which improves the shape of the breast-conserving surgery. Patients and Procedures. Twenty-eight breast cancer patients with clinically negative lymph nodes received this procedure. Methylene blue dye and technetium-99m sulfur colloid were used to be the tracker of sentinel lymph nodes (SLNs). Periareolar incision was the main surgical technique. The STORZ HD endoscopic system and some special instruments were used during the operation. Results. SLNs can be accurately located and biopsied under an endoscope without additional incisions. The SLNs detection rate, sensitivity, and false-negative rate are 88%, 80%, and 11.1%, respectively. And, the complications such as paresthesia and upper limb lymphedema are similar compared with traditional breast-conserving surgery (10.7% vs 9.8% and 7.1% vs 7.8%). Conclusion. Endoscopic technique can be used to accurately assess the status of SLNs in patients with breast cancer. Nonliposuction endoscopic breast-conserving surgery is one of the safe and alternative surgical procedures for early breast cancer.

Mucociliary Clearance in Former Tobacco Smokers with Both Chronic Obstructive Pulmonary Disease and Chronic Bronchitis and the Effect of Roflumilast.

Background: Little is known of the repeatability and reliability of mucociliary clearance (MCC) in former tobacco smokers who have both chronic obstructive pulmonary disease (COPD) and chronic bronchitis (CB). Less is known of the effect of roflumilast, a selective inhibitor of PDE4, on MCC in these patients. Methods: Former tobacco smokers with COPD and CB were treated for 4 weeks with either roflumilast, or placebo, in a randomized, crossover trial. The following were measured on two baseline and two posttreatment visits: MCC values through 90 minutes, following inhalation of 99mtechnetium sulfur colloid and gamma camera imaging; outer:inner (O:I) deposition ratio; forced expiratory volume in 1 second (FEV1); and symptom scores. Comparisons included: MCC measures through 30 minutes (MCC30), 60 minutes (MCC60), and 90 minutes (MCC90) on the two baseline visits (n = 9) and mean change [(roflumilast - baseline)-(placebo - baseline)] for MCC30, MCC60, MCC90, and FEV1 (n = 8). Associations between MCC measurements, FEV1 and O:I ratio with symptom scores were also examined. Results: Pearson correlation tests indicated good repeatability for baseline measures of MCC30, MCC60, and MCC90 and intraclass correlation coefficients indicated good reliability. Only FEV1 (percent predicted) improved significantly following roflumilast treatment. There were no statistically significant correlations between MCC measures and symptom scores. Lower FEV1 values were significantly associated with increased shortness of breath (dyspnea), and lower O:I ratios (more inner region deposition) were significantly associated with increased cough and sputum. Conclusions: Measurements of MCC30, MCC60, and MCC90 are repeatable and reliable in former tobacco smokers with both COPD and CB. One month of treatment with roflumilast did not improve MCC in this limited study. Airway narrowing in the larger, central airways of these subjects could lead to decreased FEV1, increased inner region deposition of the radiolabeled particles, and the associated increase in symptoms of dyspnea, cough, and sputum.

Abstract 17199: Airway Mucociliary Clearance is Impaired After Infant Congenital Cardiac Surgery

Introduction: A link between congenital heart disease and airway ciliary dyskinesia has been identified. Postoperative pulmonary dysfunction is highly prevalent after cardiac surgery and contributes to morbidity, mortality, and healthcare costs. We hypothesized that respiratory mucociliary clearance (MCC) would be impaired in the immediate postoperative period after infant congenital cardiac surgery. Methods: 41 infants from 5-254 days old underwent MCC scans using nebulized technetium-99m sulfur colloid either immediate postoperative or later postoperative periods after congenital cardiac surgery. Physiologic variables and medications at the time of scan were recorded. Results: There was no significant correlation between MCC and age, gender, race or any of the of the physiologic variables, such as temperature, SpO2, or FiO2, at the time of the MCC scan. MCC was lowest on the first 2 postoperative days, increased at days 3-7, and highest beyond postoperative day 7 (Fig1). Fentanyl (p=0.023) and paralytics agents (p=0.018) were significantly associated with lower MCC, while benzodiazepines (p=0.447) and dexmedetomidine (p=0.675) showed no measurable impact (Table 1). Conclusion: We show for the first time, with quantitative measurements, the near absence of infant MCC in the immediate postoperative period after congenital cardiac surgery. This may be exacerbated by opioid exposure, which should be minimized. Our results further suggest sedative alternatives such as benzodiazepines and dexmedetomidine are preferable to help optimize infant airway clearance. This may reduce ICU length of stay and improve outcomes after cardiac surgery.

Anaphylactic Reactions to Isosulfan Blue Dye During Sentinel Lymph Node Biopsy for Breast Cancer

Background: The sentinel lymph node biopsy is an alternative to axillary dissection for many breast cancer patients. Cases of anaphylactic reaction to the isosulfan blue dye used during sentinel lymph node biopsy have recently been reported. To prospectively reduce the incidence and severity of adverse reactions to isosulfan blue dye, we evaluated the incidence of severe anaphylactic reactions to isosulfan blue dye during the performance of sentinel lymph node biopsy for breast cancer at our institution. Methods: A retrospective chart review study enrolled 1,456 consecutive patients with breast cancer at our institution. Sentinel lymph node biopsy was performed using both isosulfan blue dye and technetium-99m sulfur colloid. Cases of anaphylaxis were reviewed in detail. Results: Overall, 12 (0.8%) of the 1,456 patients had severe anaphylactic reactions. All 12 patients experienced cardiovascular collapse (profound hypotension and tachycardia) and skin reactions; and patients required admission to an intensive care unit bed or equivalent setting for postoperative monitoring. No deaths or permanent disability occurred. Conclusions: Prompt recognition and aggressive treatment of anaphylactic reactions to isosulfan blue are critical to prevent an adverse outcome. Lymphatic mapping with blue dye should be performed in a setting where personnel are trained to recognize and treat anaphylaxis. J Curr Surg. 2018;8(3-4):32-34 doi: https://doi.org/10.14740/jcs365w

Computed tomography-guided preoperative localization of musculoskeletal lesions using the ROLL technique.

ObjectiveTo describe the preoperative localization of musculoskeletal lesions with the radioguided occult lesion localization (ROLL) technique.Materials and MethodsIn all cases, computed tomography-guided injection of technetium-99m sulfur colloid was performed, directly into or near the suspicious lesion, up to 36 hours before the surgical procedure. Lesions were detected intraoperatively with a gamma probe.ResultsWe report the cases of six patients submitted to radioguided surgery, including three patients with bone lesions suspicious for metastasis, two patients suspected of recurrent sarcoma, and one patient with no previous diagnosis who had a nodular lesion on the left leg. Patients tolerated the procedure well, and no complications were associated with the puncture. All marked lesions were easily identified intraoperatively and were excised with clear margins.ConclusionThe ROLL technique was effective in the intraoperative localization of occult musculoskeletal lesions, demonstrating that it is a feasible and promising technique for the surgical exploration of selected cases.

Abstract P2-01-05: A phase II clinical trial of VST-1001 (dilute fluorescein) in lymphatic mapping and sentinel lymph node localization in clinically node negative breast cancer

Abstract Background: Combined use of a radiocolloid and a vital blue dye is recommended for accurate lymphatic mapping and sentinel lymph node (SLN) identification in breast cancer. However, vital blue dyes can cause tattooing, skin necrosis and severe allergic reactions. Moreover, the vital blue dyes are only able to detect 70% or less of SLNs in large multi-center trials. Hence, there is an unmet need to develop new lymphatic mapping agents that could potentially replace vital blue dyes. We have previously, in a Phase I trial, reported on the safety of VST-1001 (dilute fluorescein) in SLN identification. Here we report the Phase II data of VST-1001 and direct visualization devices in lymphatic mapping, SLN identification, and safety in clinically node negative breast cancer. Methods: This prospective Phase II, multi-center, non-randomized, single-arm, open-label, single-dose clinical trial enrolled patients (pts) with DCIS and clinical stage I/II breast cancer eligible for SLN biopsy. All pts had SLN localization with technetium-99m-sulfur colloid (Tc99mSC) and intraoperative lymphatic mapping with 0.1% VST-1001 injected peritumorally, periareolarly, and/or intradermally. SLN radioactivity was identified with a gamma probe, and VST-1001 fluorescence was induced by light emitting diodes and detected as yellowish-green fluorescence in the visible light range with notch filter spectacles. The primary endpoint was the ability of VST-1001 to localize lymph nodes. SLN concordance of Tc99mSC radioactivity and VST-1001 fluorescence, and safety were also assessed. Results: Eighty-seven women and 2 men with a median age of 60 yrs (range, 37-77) were enrolled. Primary tumor T-stage was: 12.4% T0, 62.9% T1, 23.6% T2, and 1.1% T3. Of the 89 pts, 87 (97.8%) had at least 1 radioactive SLN, and 86 (96.6%) at least 1 fluorescent SLN. Of a total of 198 SLN identified (mean 2.2 SLN/pt), 74.2% were fluorescent and radioactive, 11.6% were radioactive only, 8.6% were fluorescent only, and 5.1% were not radioactive or fluorescent. 82.8% of all SLNs were fluorescent. Twelve (13.5%) pts had microscopic metastatic breast cancer in 14 (7.1%) SLNs. Of the 14 SLNs with metastasis, 12 (85.7%) were both radioactive and fluorescent, 1 (7.1%) fluorescent only and 1 (7.1%) not radioactive or fluorescent and only suspicious on palpation. The fluorescent only SLN was identified in a patient with only 1 SLN and without VST-1001 the metastasis would have been missed. The only adverse event related to VST-1001 was intraoperative grade 2 allergic reaction of the ipsilateral breast in one pt. Intravenous anti-histamines were administered and the erythema resolved. Conclusions: VST-1001 safely localized lymph nodes in breast cancer. VST-1001 was able to localize lymph nodes that were not radioactive and had a high co-localization concordance with Tc99mSC. VST-1001 also appears to have a higher rate of SLN localization compared to that historically reported for vital blue dyes. In light of these data, VST-1001 may be an alternative SLN localizing agent to be used in conjunction with Tc99mSC in breast cancer pts, eliminating many of adverse events observed when using vital blue dyes without compromising SLN identification. Citation Format: Ross MI, Black DM, Mittendorf EA, Porretta JM, Bedrosian I, Caudle AS, Hwang RF, Meric-Bernstam F, Babiera GV, Brulotte M, Andtbacka RHI, Matsen CB. A phase II clinical trial of VST-1001 (dilute fluorescein) in lymphatic mapping and sentinel lymph node localization in clinically node negative breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-01-05.

Sensitivity and negative predictive value for sentinel lymph node biopsy in women with early-stage cervical cancer

ObjectiveThe role of sentinel lymph node (SLN) biopsy alone for staging of early-stage cervical cancer remains controversial. We aimed to determine the validity of this technique in women with early-stage cervical cancer. MethodsWe retrospectively reviewed women with early-stage cervical cancer who underwent SLN mapping followed by complete pelvic lymphadenectomy as part of initial surgical management from August 1997 through October 2015. All modes of surgical approach were included. Lymphatic mapping was performed using blue dye, technetium-99m sulfur colloid (Tc-99), and/or indocyanine green (ICG). We determined SLN detection rates, sensitivity and negative predictive value. ResultsOne hundred eighty-eight patients were included, and 35 (19%) had lymph node metastases. At least one SLN was identified in 170 patients (90%), and bilateral SLNs were identified in 117 patients (62%). The majority of SLNs (83%) were found in the pelvis. There was no difference in detection rates between mapping agents, surgical approach, patients with and without prior conization or between patients with tumors <2cm and ≥2cm. The detection rate for bilateral SLNs was significantly lower in women with body mass index (BMI)>30kg/m2 than in women with lower BMI (p=0.03). Metastatic disease in sentinel nodes was detected by H&E staining in 78% of cases and required ultrastaging/immunohistochemistry in 22% of cases. Only one patient had a false-negative result, yielding a sensitivity of 96.4% (95% CI 79.8%–99.8%) and negative predictive value of 99.3% (95% CI 95.6%–100%). The false-negative rate was 3.6%. ConclusionsIn these women with early-stage cervical cancer, SLN biopsy had very high sensitivity and negative predictive value. We believe it is time to change the standard of care for women with early-stage cervical cancer to SLN biopsy only.

Intraoperative Injection of Technetium-99m Sulfur Colloid for Sentinel Lymph Node Biopsy in Breast Cancer Patients: A Single Institution Experience.

Background. Most institutions require a patient undergoing sentinel lymph node biopsy to go through nuclear medicine prior to surgery to be injected with radioisotope. This study describes the long-term results using intraoperative injection of radioisotope. Methods. Since late 2002, all patients undergoing a sentinel lymph node biopsy at the Yale-New Haven Breast Center underwent intraoperative injection of technetium-99m sulfur colloid. Endpoints included number of sentinel and nonsentinel lymph nodes obtained and number of positive sentinel and nonsentinel lymph nodes. Results. At least one sentinel lymph node was obtained in 2,333 out of 2,338 cases of sentinel node biopsy for an identification rate of 99.8%. The median number of sentinel nodes found was 2 and the mean was 2.33 (range: 1–15). There were 512 cases (21.9%) in which a sentinel node was positive for metastatic carcinoma. Of the patients with a positive sentinel lymph node who underwent axillary dissection, there were 242 cases (54.2%) with no additional positive nonsentinel lymph nodes. Advantages of intraoperative injection included increased comfort for the patient and simplification of scheduling. There were no radiation related complications. Conclusion. Intraoperative injection of technetium-99m sulfur colloid is convenient, effective, safe, and comfortable for the patient.

Radionuclide Esophageal Transit Scintigraphy in Primary Hypothyroidism.

Background/AimsEsophageal dysmotility is associated with gastrointestinal dysmotility in various systemic and neuroregulatory disorders. Hypothyroidism has been reported to be associated with impaired motor function in esophagus due to accumulation of glycosaminoglycan hyaluronic acid in its soft tissues, leading to changes in various contraction and relaxation parameters of esophagus, particularly in the lower esophageal sphincter. In this study we evaluated esophageal transit times in patients of primary hypothyroidism using the technique of radionuclide esophageal transit scintigraphy.MethodsThirty-one patients of primary hypothyroidism and 15 euthyroid healthy controls were evaluated for esophageal transit time using 15–20 MBq of Technetium-99m sulfur colloid diluted in 10–15 mL of drinking water. Time activity curve was generated for each study and esophageal transit time was calculated as time taken for clearance of 90% radioactive bolus from the region of interest encompassing the esophagus. Esophageal transit time of more than 10 seconds was considered as prolonged.ResultsPatients of primary hypothyroidism had a significantly increased mean esophageal transit time of 19.35 ± 20.02 seconds in comparison to the mean time of 8.25 ± 1.71 seconds in healthy controls (P < 0.05). Esophageal transit time improved and in some patients even normalized after treatment with thyroxine. A positive correlation (r = 0.39, P < 0.05) albeit weak existed between the serum thyroid stimulating hormone and the observed esophageal transit time.ConclusionsA significant number of patients with primary hypothyroidism may have subclinical esophageal dysmotility with prolonged esophageal transit time which can be reversible by thyroxine treatment. Prolonged esophageal transit time in primary hypothyroidism may correlate with serum thyroid stimulating hormone levels.

Abstract P3-01-09: A phase I clinical trial of VST-1001 (dilute fluorescein) in lymphatic mapping and sentinel lymph node localization in clinically node negative breast cancer

Abstract Background: Combined use of a radiocolloid and a vital blue dye is recommended for accurate lymphatic mapping and sentinel lymph node (SLN) identification. However, vital blue dyes can cause tattooing, skin necrosis and allergic reactions. Hence, there is a great need for new lymphatic mapping agents. Here we describe the novel use of VST-1001 (dilute fluorescein) and direct visualization devices in lymphatic mapping and SLN identification. Methods: A prospective, non randomized, single arm, open label, single dose, dose-finding Phase I clinical trial in patients (pts) with high-grade DCIS and clinical stage I/II breast cancer eligible for SLN biopsy was performed. All pts had SLN localization with technetium-99m-sulfur colloid (Tc99mSC) and intraoperative lymphatic mapping with VST-1001 injected peritumorally, periareolarly, and/or intradermally. SLN radioactivity was identified with a gamma probe, and VST-1001 fluorescence was induced by light emitting diodes and detected as a yellowish-green fluorescence in the visible light range with notch filter spectacles. The primary endpoints were safety, ability of VST 1001 to localize lymph nodes, and the optimal dose of VST-1001. SLN concordance of Tc99mSC radioactivity and VST-1001 fluorescence was also assessed. Results: Fifteen women with a median age of 60 yrs (range, 43-80) were enrolled. In cohort 1, 5 pts received 0.01% VST-1001. All patients had at least 1 SLN that was fluorescent and radioactive. A total of 22 SLNs were identified, many with faint fluorescence. Per protocol, the dose of VST-1001 was increased, and in cohort 2, 10 patients received 0.1% VST-1001. All 10 (100%) pts in cohort 2 had at least 1 SLN that was fluorescent and radioactive. Of a total of 24 SLNs identified, 20 (83%) were fluorescent and radioactive, 2 (8%) were radioactive only, and 2 (8%) were fluorescent only. Four SLNs in 3 patients contained micrometastatic breast cancer; all 4 SLNs were radioactive and fluorescent. There were no adverse events related to VST-1001. A Phase II clinical trial is currently accruing. Conclusions: VST-1001 safely localized lymph nodes in breast cancer. VST-1001 was able to localize lymph nodes that were not radioactive and had a high concordance with Tc99mSC. VST-1001 may be a novel alternative to vital blue dyes in lymphatic mapping and lymph node localization. Citation Format: Ross MI, Bedrosian I, Black DM, Mittendorf EA, Caudle AS, Babiera GV, Hwang RF, Meric-Bernstam F, Grissom CB, Brulotte M, Andtbacka RHI. A phase I clinical trial of VST-1001 (dilute fluorescein) in lymphatic mapping and sentinel lymph node localization in clinically node negative breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-01-09.

Estimation of Residual Peritoneal Volume Using Technetium-99m Sulfur Colloid Scintigraphy.

Residual peritoneal volume (RPV) may contribute in the development of ultrafiltration failure in patients with normal transcapillary ultrafiltration. The aim of this study was to estimate the RPV using intraperitoneal technetium-99m Sulfur Colloid (Tc). Twenty patients on peritoneal dialysis were studied. RPV was estimated by: 1) intraperitoneal instillation of Tc (RPV-Tc) and 2) classic Twardowski calculations using endogenous solutes, such as urea (RPV-u), creatinine (RPV-cr), and albumin (RPV-alb). Each method's reproducibility was assessed in a subgroup of patients in two consecutive measurements 48 h apart. Both methods displayed reproducibility (r = 0.93, p = 0.001 for RPVTc and r = 0.90, p = 0.001 for RPV-alb) between days 1 and 2, respectively. We found a statistically significant difference between RPV-Tc and RPV-cr measurements (347.3 ± 116.7 vs. 450.0 ± 67.8 ml; p =0.001) and RPV-u (515.5 ± 49.4 ml; p < 0.001), but not with RPV-alb (400.1 ± 88.2 ml; p = 0.308). A good correlation was observed only between RPV-Tc and RPV-alb (p < 0.001). The Tc method can estimate the RPV as efficiently as the high molecular weight endogenous solute measurement method. It can also provide an imaging estimate of the intraperitoneal distribution of RPV.

Displacement of the Spleen Mimicking Renal Cell Cancer Recurrence Post-Nephrectomy: A Case Report.

Local regional recurrence of renal cell cancer post-nephrectomy most often occurs within three years after surgery. Post-nephrectomy, many processes may mimic RCC recurrence. We present the case of a 75 year-old Caucasian male patient with a mass in his renal fossa post-nephrectomy for renal cell cancer, suggesting local recurrence. Use of the technetium-99m sulfur colloid scan showed that the mass was his spleen which had been displaced into the renal fossa. With high index of suspicion, characterization of these processes as splenic in origin would prevent subjecting patients to risks of biopsy or even surgery.

Hyperglycemia potentiates the slowing of gastric emptying induced by exogenous GLP-1.

Acute hyperglycemia markedly slows gastric emptying. Exogenous GLP-1 also slows gastric emptying, leading to diminished glycemic excursions. The primary objective was to determine whether hyperglycemia potentiates the slowing of gastric emptying induced by GLP-1 administration. Ten healthy participants were studied on 4 separate days. Blood glucose was clamped at hyperglycemia using an intravenous infusion of 25% dextrose (∼12 mmol/L; hyper) on 2 days, or maintained at euglycemia (∼6 mmol/L; eu) on 2 days, between t = -15 and 240 min. During hyperglycemic and euglycemic days, participants received intravenous GLP-1 (1.2 pmol/kg/min) and placebo in a randomized double-blind fashion. At t = 0 min, subjects ingested 100 g beef mince labeled with 20 MBq technetium-99m-sulfur colloid and 3 g 3-O-methyl-glucose (3-OMG), a marker of glucose absorption. Gastric emptying was measured scintigraphically from t = 0 to 240 min and serum 3-OMG taken at regular intervals from t = 15 to 240 min. The areas under the curve for gastric emptying and 3-OMG were analyzed using one-way repeated-measures ANOVA with Bonferroni-Holm adjusted post hoc tests. Hyperglycemia slowed gastric emptying (eu/placebo vs. hyper/placebo; P < 0.001) as did GLP-1 (eu/placebo vs. eu/GLP-1; P < 0.001). There was an additive effect of GLP-1 and hyperglycemia, such that gastric emptying was markedly slower compared with GLP-1 administration during euglycemia (eu/GLP-1 vs. hyper/GLP-1; P < 0.01). Acute administration of exogenous GLP-1 profoundly slows gastric emptying during hyperglycemia in excess of the slowing induced by GLP-1 during euglycemia. Studies are required to determine the effects of hyperglycemia on gastric emptying with the subcutaneously administered commercially available GLP-1 agonists in patients with type 2 diabetes.

Radiolabeled mannosylated dextran derivatives bearing an NIR-fluorophore for sentinel lymph node imaging.

Current methods for sentinel lymph node (SLN) mapping involve the use of radioactivity detection with technetium-99m sulfur colloid and/or visually guided identification using a blue dye. To overcome the kinetic variations of two individual imaging agents through the lymphatic system, we report herein on two multifunctional macromolecules, 5a and 6a, that contain a radionuclide ((99m)Tc or (68)Ga) and a near-infrared (NIR) reporter for pre- and/or intraoperative SLN mapping by nuclear and NIR optical imaging techniques. Both bimodal probes are dextran-based polymers (10 kDa) functionalized with pyrazole-diamine (Pz) or 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) chelating units for labeling with fac-[(99m)Tc(CO)3](+) or (68)Ga(III), respectively, mannose units for receptor targeting, and NIR fluorophore units for optical imaging. The probes allowed a clear visualization of the popliteal node by single-photon emission computed tomography (SPECT/CT) or positron emission tomography (PET/CT), as well as real-time optically guided excision. Biodistribution studies confirmed that both macromolecules present a significant accumulation in the popliteal node (5a: 3.87 ± 0.63% IA/organ; 6a: 1.04 ± 0.26% IA/organ), with minimal spread to other organs. The multifunctional nanoplatforms display a popliteal extraction efficiency >90%, highlighting their potential to be further explored as dual imaging agents.

Indocyanine green and fluorescence lymphangiography for sentinel lymph node identification in cutaneous melanoma.

Sentinel lymph node (SLN) biopsy has become the standard method of determining regional lymph node involvement in cutaneous melanoma. Although traditionally performed via injection of radioisotope tracers and blue dyes, fluorescent lymphangiography with indocyanine green (ICG) is an attractive alternative. Fifty two consecutive patients with cutaneous melanoma of the trunk or extremities underwent SLNB. Preoperative lymphoscintigraphy was performed with technetium-99m sulfur colloid (TSC). Peritumoral intradermal injection of isosulfan blue (ISB) and ICG was then performed. Successful identification of a sentinel lymph node via each modality was then assessed. A total of 77 lymph nodes were identified from the 52 patients (range 1-3). The majority of melanomas were extremity-based, superficial spreading type, and had SLN localized to the axilla. There were no complications related to IcG administration. Rates of SLN detection were 96.2% for TSC, 59.6% for ISB, and 88.5% for IcG (P < 0.05 for ICG vs ISB). On univariate logistic regression analysis, no factors were found to be associated with failure of ICG. Fluorescent lymphangiography using ICG is an effective method of SLN identification in patients with cutaneous melanoma of the trunk and extremities. When ICG and TSC are used in combination, ISB offers no additional advantage and may be safely omitted.

Functional hyposplenism is an important and underdiagnosed immunodeficiency condition in children.

Few studies have focused on paediatric hyposplenism/asplenism, in which splenic phagocytic activity is diminished or absent in an anatomically present spleen. This study aimed to evaluate clinical findings, laboratory tests and prognosis of children with functional hyposplenism/asplenism. The study group comprised 74 children who had liver/spleen technetium-99m sulphur colloid scintigraphy from 2002 to 2008. Information collected included demographic features, background diseases, blood smear findings, indications for scintigraphy and outcome. Children with functional hyposplenism were followed until 2012. We found that 34 patients had functional hyposplenism/asplenism. The main indications for scintigraphy in the hyposplenic patients were persistent thrombocytosis and recurrent infections. Associated conditions included immunodeficiencies, autoimmune diseases, malignancies and genetic disorders. Main infections were sinopulmonary infections, bacteraemia and sepsis. The major pathogens were Streptococcus pneumoniae and Haemophilus influenza group A. There was no correlation between the presence of Howell-Jolly bodies in blood smear with clinical disease severity or scintigraphic findings. Repeated scintigraphy showed spontaneous normalisation in 40% of patients. Functional hyposplenism is an important and underdiagnosed immunodeficiency condition in children, associated with various clinical conditions including prolonged unexplained thrombocytosis, immune deficiency and autoimmunity. Technetium-99m sulphur colloid scintigraphy is the method of choice for evaluating splenic function.

Pulmonary lymph node charting in normal dogs with blue dye and scintigraphic lymphatic mapping

The prognosis of dogs with primary lung tumors and lymph node metastasis is poorer than of dogs without metastasis. Biopsy of intrathoracic lymph nodes is recommended, but without specific guidelines. This study investigated incorporation of a human lymph node classification in normal dogs with intercostal thoracotomies. Methylene blue and technetium-99m sulfur colloid lobar injections were used for enhanced nodal identification. Descriptive comparisons were made for lymph node resections utilizing both veterinary and human anatomic lymph node charts. A median of 2 (range 1–4) lymph nodes were removed per hemithorax in vivo versus a median 6.5 (range 2–8) lymph nodes removed ex vivo from each hemithorax following in vivo dissections. Incorporation of a human thoracic lymph node classification system may be useful for future clinical application in dogs. Future use of either methylene blue or technetium for canine thoracic lymphadenectomy needs to be evaluated further.