Time to Procedure, Nuclear Imaging and Clinicopathological Characteristics as Predictive Factors for Sentinel Lymph Node Metastasis in Cutaneous Melanoma: A Single-Center Analysis.

OBJECTIVE: Sentinel lymph node (SLN) biopsy is a widely accepted staging procedure for cutaneous melanoma patients who are at risk of clinically occult nodal metastases. Numerous predictive factors for regional lymph node metastases have been identified; however, few have been found to be reproducibly significant. Also, the role of blue dye in identification was questioned in recent trials. Time to procedure was also found to be predictive of SLN positivity, but this was not confirmed in other studies. In our study, predictive factors for metastatic involvement of SLN were analyzed, together with the role of addition blue dye in imaging on detection rate and false-negative SLN rate. An impact of time interval to procedure on the rate of SLN positivity was also explored. METHODS: Data analysis was done in 362 cutaneous melanoma patients who underwent lymphoscintigraphy and SLN biopsy at our institution from 2010 to 2016, with a median follow-up of 29 months (1-98 months). To delineate the relation of each variable (demographical, time to procedure, and clinical and pathological variables, as well as the presence of in-transit nodes, the number of draining basins, and SLN localization on scintigraphy) with positive SLN status, we used univariate logistic regression with odds ratios representing effect size. RESULTS: Metastatic involvement SLN was found in 67 (18.8%) of 356 patients. Detection rate was similar with or without further intraoperative SLN identification with blue dye (98.8% vs 98.17%, P > 0.05). Time to procedure was not associated with higher SLN positivity rate (P > 0.05). In univariate analysis, Breslow thickness (P < 0.001), primary ulceration lesion (P = 0.001), and lymphovascular invasion (P = 0.006) were strongly correlated with SLN positivity, as well as the site of primary tumor (P = 0.024), tumor-infiltrating lymphocytes (TILs) (P = 0.021), and sex (P = 0.026). In multivariate analysis, Breslow thickness and TILs were found to be significant independent predictors of SLN status (P < 0.05). CONCLUSIONS: Addition of blue dye did not improve SLN detection rate; time to procedure was not found to be associated with higher SLN biopsy positivity rates. Breslow thickness and TILs, as a marker of immune response to tumor, were consistently found to be significant independent predictors of SLN status.

Renal output efficiency and normalized residual activity examined by technetium-99m-DTPA renography have by far greater specificity to diagnose obstructive disease as compared to other conventional parameters of the renogram. First such study of output efficiency.

OBJECTIVE: The aim of this study was to assess the diagnostic ability of renal output efficiency (OE), normalized residual activity (NORA) and conventional interpretation of the diethylene triamine pentaacetic acid (99mTc-DTPA) diuretic renogram (CIR) in diagnosing urine flow obstruction. SUBJECTS AND METHODS: Group A consisted of 73 obstructed kidneys and Group B of 80 kidneys with dilated upper urinary tract. Forty eight kidneys were examined as the control Group C. A 40min acquisition with 240 of 10sec images was applied. Furosemide was administered after 20min (F+20). Post-void image was acquired at 50min. Output efficiency was calculated at 20min (OE20) and 20min after furosemide test (OE40) and NORA at 20min (NORA20) and on the post-micturition acquisition (NORAPM). RESULTS: Both the above parameters (OE40 and NORAPM) had high sensitivity (92% and 97%), specificity (99% for both) and accuracy (95% and 98%) in differentiating between obstructed and dilated unobstructed kidneys. The test of NORAPM correctly reclassified 40 out of 41 indeterminate or false positive results of the conventional interpretations of renograms (CIR) as obstructed (12 cases) or dilated (28 cases). Cut-off values for obstruction were <80% and ≥0.23 for OE40 and NORAPM, respectively. Compared to CIR, both parameters showed better specificity, especially NORAPM. CONCLUSION: Factors of OE40 and especially NORAPM of the renogram by 99mTc-DTPA were able to diagnose urine outflow obstruction better than CIR. Specifically, these factors well differentiated obstruction from urinary tract dilatation.

Positive 99mTc-MIBI and the subtraction parathyroid scan are related to intact parathyroid hormone but not to total plasma calcium in primary hyperparathyroidism.

OBJECTIVE: Primary hyperparathyroidism (pHPT) is characterised by increased parathyroid hormone (PTH) secretion and consequently increased plasma calcium. During the last few decades parathyroid scintigraphy (PS), is applied in almost all patients with pPHT before surgery and specifically before minimally invasive parathyroidectomy. The aim of this study was to find the best cut-off levels of total plasma calcium and intact PTH (iPTH) that correlate with positive technetium-99m-methoxy isobutyl isonitrile (99mTc-MIBI) PS and with positive subtraction PS (SPS) in patients with pHPT and thus the positive diagnostic value of these PS. SUBJECTS AND METHODS: We studied 50 patients, operated for pHPT, aged from 22-78 years, (median age 60 years), 45 female and 5 male, with a total number of 57 parathyroid glands (PG), (46 adenomas and 11 hyperplasias). All patients underwent SPS before surgery. Static scintigrams of the head, neck and chest were performed 15min after the intravenous (i.v.) injection of 740MBq of 99mTc-MIBI. Late scintigrams of the head, neck and chest were performed 2h and 3h after the injection of 99mTc-MIBI. Four to 24h after the washout of 99mTc-MIBI from the parathyroid and the thyroid glands, we injected i.v. 185MBq of 99mTc-pertechnetate (99mTcP) and after 15min we performed the PS. Normalization and motion correction of the early 99mTc-MIBI scan and the 99mTcP followed. We then subtracted the 99mTcP from the 99mTc-MIBI scan. The areas of increased uptake on the 99mTc-MIBI scan visible at the early and late or at the subtraction images represented the hyperfunctioning tissue of the enlarged and hyperfunctioning parathyroid glands. Scintigraphic findings were graded subjectively, from 1 to 5 depending on the degree of the uptake of the radiopharmaceutical. Normal iPTH levels were between 10.0-65.0pg/mL and normal total plasma calcium between 2.13-2.65mmoL/L. RESULTS: Of all patients 12/50 and 38/50 had both PS positive grade 4 and very positive grade 5 findings respectively. In all patients iPTH levels ranged from 54 to 837pg/mL, median value 187.0±133.8pg/mL, and total plasma calcium ranged from 2.40 to 3.83mmoL/L, median value, 2.87±0.237mmoL/L. In 43 patients, both calcium and the iPTH levels were elevated. Strong positive correlation was found between scintigraphic findings and levels of iPTH: P=0.003. A significant relation between plasma calcium levels and different grades of scintigraphic findings was not found, although significant correlation was found between iPTH and plasma calcium levels (P=0.021). CONCLUSION: In patients with pHPT, the 99mTc-MIBI PS and the subtraction PS showed a strong correlation to iPTH (P=0.003) but not to total plasma calcium levels indicating the importance of both the 99mTc-MIBI and the subtraction parathyroid scans to indicate pHPT.

Technetium-99m-dimercaptosuccinic acid renal scintigraphy can guide clinical management in congenital hydronephrosis.

OBJECTIVE: The purpose of this study was to evaluate damage of the kidney with technetium-99m-dimercaptosuccinic acid (99mTc-DMSA) scintigraphy in children with congenital hydronephrosis (CH) and the influence of other postnatal associated diagnoses on abnormal 99mTc-DMSA findings. SUBJECTS AND METHODS: 99mTc-DMSA scintigraphy in 54 children (17 girls and 37 boys), aged from 2 months to 5 years (median 11 months) with 66 congenital hydronephrotic renal units (RU) (42 unilateral hydronephrosis-29 boys and 13 girls; 12 bilateral hydronephrosis-8 boys and 4 girls) was performed. Male/female ratio was 2,2:1, unilateral/bilateral hydronephrosis ratio was 4:1. Hydronephrosis classified into three groups according to ultrasound measurement of the antero-posterior pelvic diameter APD): mild (APD 5-9.9mm) was present in 13/66RU, moderate (APD 10-14.9mm) in 25/66RU, and severe (APD≥15mm) in 28/66RU. Simple hydronephrosis was present in 15RU, and the postnatal associated clinical diagnosis were vesicoureteric reflux (VUR) in 21, pelviureteric junction (PUJ) obstruction in 7, pyelon et ureter duplex in 11, megaureter in 11 and posterior urethra valves in 1RU, respectively. Static renal scintigraphy was performed 2 to 3 hours after intravenous (iv) injection of 99mTc-DMSA using a dose of 50µCi/kg (1.85MBq/kg; minimal dose: 300µCi). Four views (posterior, left and right posterior oblique and anterior) were obtained with a head gamma camera "Orbiter" filtered with high resolution parallel whole collimator. All images were stored in an Pegasys computer with a matrix size of 256×256. The relative kidney uptake (RKU) between the left and right kidney was calculated as an average number counts from anterior and posterior view. Renal pathology was defined as inhomogenous or focal/multifocal uptake defects of radiopharmaceutical in hydronephrotic kidney or as split renal uptake of <40%, and poor kidney function was defined as split renal uptake <10%. Descriptive and analytical statistics (SPSS version 20.0) was performed. Analytical statistics implied the non-parametric Mann-Whitney test for determination of statistically significant difference between the normal and pathological findings on 99mTc-DMS scan. The default level of significance was P<.05. RESULTS: Our 99mTc-DMSA scintigraphy findings in children with ANH were: decreased or enlarged kidney with inhomogeneous kidney uptake radiopharmaceutical in 22, irregular shape kidney with inhomogeneous accumulation of radiopharmaceutical in 3, connected (fused) kidney in 1 patient, and poorly or nonvisual kidney in 14RU respectively (total 40/66RU with pathological 99mTc-DMSA finding, 60,6%). Relative accumulation in hydronephrotic kidney was less or equal to 40% in 17RU, less than 10% in 14RU and inhomogeneous radiopharmaceutical uptake with relative accumulation over 40% was detected in 9RU. Regular kidney morphology with homogeneous accumulation of radiopharmaceutical (normal DMSA scintigraphy finding) were found in 26/66RU (39,4%). Statistically significant correlation between the degree of the hydronephrosis (APD) and 99mTc-DMSA scan findings (P<0.001) and between the degree of the VUR and DMSA scan finding (P=0.002) was established. In our study, other associated diagnosis were not statistically correlated with pathological findings on 99mTc-DMSA scan due to low number of patients. CONCLUSION: On the basis of these results (60% pathological findings) we recommend DMSA scintigraphy in the evaluation renal pathology in children with congenital hydronephrosis. Greater number of patients is needed for the estimation of the associated diagnosis (other than VUR) influence on the renal parenchymal damage in children with CH.

Lymphoscintigraphy and sentinel lymph node biopsy, in cutaneous melanoma staging and treatment decisions.

OBJECTIVE: Sentinel lymph node biopsy (SLNB) is a widely accepted method in the management of clinically localized cutaneous melanomas. The aim of this study was to report the results on patients scheduled for preoperative lymphoscintigraphy and SLNB for staging and further treatment planning. SUBJECTS AND METHODS: Two hundred and one patients (115 male and 86 female, median age 57 years, range 9-81) with cutaneous melanoma having undergone SLB at Military Medical Academy between November 2010 and October 2014, were recruited for retrospective study. Dual labeling method (Tc-99m Nanocolloid (blue dye) was used. In order to delineate the relation between patients' tumors and scintigraphic characteristics with positive SLN findings, we examined all variables by univariate logistic regression with odd ratios representing the size effect. RESULTS: The overall identification rate of SLN was 98.5%. One or more positive SLN were seen in 47 (23.4%) of the patients. Drainage to one regional basin was noticed in 176 (88%) and multiple drainage regions, up to three, was noticed in 24 patients (12%). Transit lymph nodes were detected in 20 patients (10%). The characteristics that were assotiated significatly with sentinel lymph node metastases were Breslow thickness, nodular melanoma histological subtype and acral localization. CONCLUSION: Besides the well established primary tumor thickness being a predictor of SLN malignancy, we observed: acral body site location and nodular melanoma histological subtype to be significant independent factors in increasing the risk for regional metastases. Our results suport the clinical usefulness of SLNB within a multidisciplinary approach (dermatooncology, plastic/head and neck surgery, pathology, nuclear medicine), as a reliable method in staging and for treatment planning in melanoma patients.

Regional lymph node metastases in cutaneous melanoma: a single-center analysis from southeast europe.

OBJECTIVE: Sentinel lymph node biopsy is the standard of care for nodal staging in clinically node-negative melanoma patients. Our goal was to present 10-year results of sentinel lymph node biopsy at our institution and to evaluate the clinicopathologic factors as potential predictors of sentinel lymph node and non-sentinel lymph node metastatic involvement in patients with cutaneous melanoma. METHODS: We have analyzed clinicopathologic and lymphoscintigraphic characteristics in 420 patients with cutaneous melanoma who underwent sentinel lymph node biopsy between 2010 and 2019. In addition, we have examined the results of group of patients with positive sentinel lymph node biopsy undergoing complete lymph node dissection. RESULTS: The overall detection rate of sentinel lymph node biopsies was 97.1%, of which 18.8% was metastatic. Drainage to one regional basin was seen in 345 patients (83.1%) and to multiple drainage regions in 71 patients (17%). In-transit lymph nodes were detected in 20 patients. On univariate logistic regression analysis, male gender, primary tumor thickness with nodular histology, acral location, presence of ulceration, and the number of nodes harvested were significantly associated with sentinel lymph node biopsy status (p < 0.05). On multivariate analysis, the Breslow thickness was the only independent predictor of sentinel lymph node biopsy status. The metastases in non-sentinel lymph node found in 26 patients with positive sentinel lymph node (35.6%) correlated on univariate, as well as on multivariate logistic regression, with tumor subtype and number of sentinel lymph node harvested. CONCLUSIONS: In addition to the well-established primary tumor thickness as a predictor of sentinel lymph node biopsy positivity, we observed acral location and nodular melanoma subtype to significantly enhance the risk of metastases in sentinel lymph node(s). Primary tumor histology and number of nodes harvested were the only statistically significant variables predicting the non-sentinel lymph node status on multivariate analysis. Lymphoscintigraphy imaging characteristics were not significantly associated with sentinel lymph node status.

Interobserver reproducibility of mercaptoacetyltriglicine renography in children and adults with suspected obstruction: parameters of drainage and function calculated by International Atomic Energy Agency software.

OBJECTIVE: The aim of this study was to estimate interobserver reproducibility of Tc-99m mercaptoacetyltriglycine renography in children and adults by assessing the parameters of the International Atomic Energy Agency (IAEA) software for the analysis of dynamic renal studies. METHODS: The renograms of 65 children and 65 adults covered a wide age range, different quality of drainage, overall function and differential renal function (DRF). Three observers were processing parameters of the IAEA software. Normalized residual activity at 20 min (NORA20), NORA on the postmicturition acquisition (NORApm), PM to maximum renal count ratio (PM/max), output efficiency at 20 min (OE20), OE 20 min after diuretic stimulation (OEF + 20), whole kidney mean transit time (MTT) and DRF by integral and Rutland-Patlak were calculated by observers. RESULTS: The overall agreement between three observers was almost perfect [the average intraclass correlation coefficient (ICC) above 0.99] in children and adults, with no significant difference between the parameters of renal drainage, transit and DRF. ICCs for all parameters were higher than 0.980 in children under 12 months, even slightly greater for PM/max and OEF+20. In children with poor/incomplete drainage and DRF below 40%, ICCs were above 0.98. In the subgroup of adults with impaired overall tubular extraction rate, level of reproducibility was almost perfect. Slightly lower but still insignificant values of ICC were presented in adults with poor/incomplete drainage. CONCLUSION: Our results indicate an excellent interobserver reproducibility for all quantitative parameters of IAEA software in both pediatric and adult patients.

Diuretic 99mTc DTPA renography in assessment of renal function and drainage in infants with antenatally detected hydronephrosis.

BACKGROUND/AIM: The controversy over the postnatal management of infants with antenataly detected hydronephrosis (ANH) still exists. We presented the results of diuretic 99mTc diethylenetriamine pentaacetic acid (DTPA) renography in 30 infants with the antenatal diagnosis of unilateral renal pelvic dilatation. The aim of this study was to assess the renal function determined by the pattern of drainage and split renal function (SRF) on diuretic renography and to correlate these findings with anteroposterior pelvic diameter (APD) estimated by ultrasonography. METHODS: A total of 30 infants with 60 renal units (RU) (25 boys and 5 girls, median age 6.0 months, range 2-24) presented with unilateral hydronephrosis on ultrasound in the newborn period, underwent DTPA diuretic renal scintigraphy (F+15 protocol). The median APD evaluated on perinatal ultrasound was 15 mm (range 5-30). The postnatal associated clinical diagnosis were pelviureteric junction obstruction (PUJ), simple hydronephrosis, megaureter, vesicoureteral reflux (VUR) and posterior urethral valves in 11, 10, 6, 2 and 1 infant, respectively. Images and Tmax/2 after diuretic stimulation on the background subtracted renographic curves were used as the criteria for classifying the drainage as good, partial, and poor or no drainage. The SRF was calculated with the integral method. RESULTS: Good drainage was shown in 36/60, partial drainage in 13/60 and poor or no drainage in 11/60 RU. The SRF > 40% was observed in 55/60 RU, with no RU showing SRF lower than 23.5%. In infants with severe ANH the obstruction was not excluded in 94.1%. CONCLUSION: Diuretic renography in antenatally detected hydronephrosis should be a useful tool in postnatal follow up, especially in differentiating nonobstructive hydronephrosis from obstructive. It is also importanat to assess and monitor the SRF. Our results suggest that even in the presence of partial or no drainage, SRF may not be significantly impaired.