Prediction of Cervical Lymph Node Metastasis in Clinically Node-Negative T1 and T2 Papillary Thyroid Carcinoma Using Supervised Machine Learning Approach

Papillary thyroid carcinoma (PTC) is generally considered an indolent cancer. However, patients with cervical lymph node metastasis (LNM) have a higher risk of local recurrence. This study evaluated and compared four machine learning (ML)-based classifiers to predict the presence of cervical LNM in clinically node-negative (cN0) T1 and T2 PTC patients. The algorithm was developed using clinicopathological data from 288 patients who underwent total thyroidectomy and prophylactic central neck dissection, with sentinel lymph node biopsy performed to identify lateral LNM. The final ML classifier was selected based on the highest specificity and the lowest degree of overfitting while maintaining a sensitivity of 95%. Among the models evaluated, the k-Nearest Neighbor (k-NN) classifier was found to be the best fit, with an area under the receiver operating characteristic curve of 0.72, and sensitivity, specificity, positive and negative predictive values, F1 and F2 scores of 98%, 27%, 56%, 93%, 72%, and 85%, respectively. A web application based on a sensitivity-optimized kNN classifier was also created to predict the potential of cervical LNM, allowing users to explore and potentially build upon the model. These findings suggest that ML can improve the prediction of LNM in cN0 T1 and T2 PTC patients, thereby aiding in individual treatment planning.

18F-FDG PET/CT value in the detection of seminoma and correlation with CT and tumor marker levels - up to 8 years of follow-up

OBJECTIVE

Positron emission tomography/computed tomography using fluorine-18 fluoro-deoxyglucose (¹⁸F-FDG PET/CT) is not routinely used for diagnosis of testicular carcinoma. Unlike CT which cannot confirm with certainty the nature of the lesions, especially in post-therapy setting, ¹⁸F-FDG PET/CT detects active disease by showing increased glucose metabolism within the lesions.

AIM

Determination of ¹⁸F-FDG PET/CT usefulness in detection of seminoma, therapy response evaluation and comparison to CT findings and tumor marker levels.

MATERIAL AND METHODS

Eighty-two men (age 39.8±10.1) after orchiectomy and histopathological confirmation of seminoma were included in this study. Indications for ¹⁸F-FDG PET/CT were initial staging, restaging after chemo/radiotherapy with positive/uncertain CT, suspected recurrence on CT, elevated tumor markers. All patients had clinical follow-up of up to 8 years (median 33.5) after the first ¹⁸F-FDG PET/CT examination. Degree of metabolic activity was analyzed visually and semi-quantitatively using maximum standardized uptake value(SUVmax).

RESULTS

Fluorine-18-FDG PET/CT was true positive in 36 patients (43.9%) with average SUVmax of 7.9±4.8.Recurrence was mostly found in retroperitoneal lymph nodes and distant metastases in lungs, bones, liver. Six findings were false positive and 3 false negative. Sensitivity, specificity, accuracy of ¹⁸F-FDG PET/CT were 92.3%, 86.0%, 89.0% and of CT 60.8%, 66.6%, 63.4%. Pearson Chi-square test showed statistically significant difference between the results of ¹⁸F-FDG PET/CT and CT (P=0.016). Significant correlation was found between positive ¹⁸F-FDG PET/CT findings and levels of LDH (P=0.043), while non-significant between AFP, β-hCG (P>0.05).

CONCLUSION

Fluorine-18-FDG PET/CT was superior to CT in evaluation of therapy response, active disease in residual tissue and normal size lymph nodes, as well as when CT was negative and tumor markers were elevated. Elevated lactate dehydrogenase (LDH) contributes to positive ¹⁸F-FDG PET/CT findings.

EANM recommendations based on systematic analysis of small animal radionuclide imaging in inflammatory musculoskeletal diseases

Inflammatory musculoskeletal diseases represent a group of chronic and disabling conditions that evolve from a complex interplay between genetic and environmental factors that cause perturbations in innate and adaptive immune responses. Understanding the pathogenesis of inflammatory musculoskeletal diseases is, to a large extent, derived from preclinical and basic research experiments. In vivo molecular imaging enables us to study molecular targets and to measure biochemical processes non-invasively and longitudinally, providing information on disease processes and potential therapeutic strategies, e.g. efficacy of novel therapeutic interventions, which is of complementary value next to ex vivo (post mortem) histopathological analysis and molecular assays. Remarkably, the large body of preclinical imaging studies in inflammatory musculoskeletal disease is in contrast with the limited reports on molecular imaging in clinical practice and clinical guidelines. Therefore, in this EANM-endorsed position paper, we performed a systematic review of the preclinical studies in inflammatory musculoskeletal diseases that involve radionuclide imaging, with a detailed description of the animal models used. From these reflections, we provide recommendations on what future studies in this field should encompass to facilitate a greater impact of radionuclide imaging techniques on the translation to clinical settings.

The Relationship Between 99mTc-Pertechnetate Hand Perfusion Scintigraphy and Nailfold Capillaroscopy in Systemic Sclerosis Patients: A Pilot Study

Objectives

This study aims to assess the possible relationship between ^99mTc-pertechnetate hand perfusion scintigraphy (HPS) and nailfold capillaroscopy (NC) in systemic sclerosis (SSc) patients.

Patients and methods

The study group consisted of 25 SSc patients (6 males; 19 females; mean age 54.2±9.7 years; range, 32 to 67 years), 18 female patients with primary Raynaud's phenomenon (PRP) (mean age 47.1±9.5 years; range, 34 to 65 years) and 10 healthy individuals (3 males, 7 females; mean age 52.7±12.6 years; range, 37 to 73 years). NC and ^99mTc-pertechnetate HPS were performed in all examinees. The capillaroscopic findings were classified as normal or scleroderma pattern ("early", "active", or "late"). The fingers-to-palm ratios were calculated for both blood flow (BF) and blood pool (BP) phases of the ^99mTc-pertechnetate HPS.

Results

Systemic sclerosis patients showed a significantly lower BP ratio than PRP patients and healthy subjects (p=0.004). No statistically significant difference was observed between the SSc and PRP patients in respect to BF ratio. A gradual decrease of BF and BP with the severity of NC microangiopathy pattern ("early", "active" or "late") was found in SSc patients, while the differences were not statistically significant. Patients with diffuse SSc showed lower BF and higher BP than those with limited SSc, while these differences were without statistical significance. There was no significant correlation between BF or BP values and type of SSc (limited or diffuse) (p=0.77 versus p=0.54, respectively) as well as three microangiopathy patterns (p=0.22 versus p=0.54, respectively).

Conclusion

^99mTc-pertechnetate HPS improves the evaluation of vascular damage in SSc patients. There is no direct relationship between NC and ^99mTc-pertechnetate HPS; however, the two methods complement each other in the assessment of microcirculation in SSc.

Clinical relevance of 18F-FDG PET/CT in the postoperative follow-up of patients with history of medullary thyroid cancer

BACKGROUND

The aim of the study was evaluation of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography with computed tomography (PET/CT) in the detection of active disease in the patients with suspected recurrence of the medullary thyroid carcinoma (MTC).

PATIENTS AND METHODS

18F-FDG PET/CT investigation was performed in 67 patients, investigated from 2010 to 2019. _ Follow up was performed from 6 to 116 months after surgery (median 16.5 months, x± SD = 29±28.9 months). Twenty five of 67 patients underwent 99mTc-dimercaptosuccinic acid (99mTc-DMSA) scintigraphy, 11 underwent somatostatin receptor scintigraphy (SRS) with 99mTc-HYNIC TOC while 11 123I-metaiodobenzylguanidine (MIBG) scintigraphy.

RESULTS

From 67 patients, 35 (52.2%) had true positive 18F-FDG PET/CT findings (TP). Average maximal standardized uptake value (SUVmax) for all TP lesions was 5.01+3.6. In 25 (37.3%) patients findings were true negative (TN). Four (6%) patients had false positive (FP) findings while three (4.5%) were false negative (FN). Thus, sensitivity of the 18F-FDG PET/ CT was 92.11%, specificity 86.21%, positive predictive value 89.74%, negative predictive value 89.29% and accuracy 89.55%. In 27 patients (40%) 18F-FDG PET/CT finding influenced further management of the patient.

CONCLUSIONS

18F-FDG PET/CT has high accuracy in the detection of metastases/recurrences of MTC in patients after thyroidectomy as well as in evaluation and the appropriate choice of the therapy.

Somatostatin receptor scintigraphy in the follow up of neuroendocrine neoplasms of appendix

BACKGROUND

Neuroendocrine tumors of appendix (ANETs) known as carcinoids, are rare endocrine neoplasms originated from enterochromaffin cells of gastrointestinal tract. ANETs are the third most frequent (16.7%) gastrointestinal neuroendocrine tumors, with the incidence of 0.08-0.2 cases/100000 during one year. Incidental ANETs occur in 0.2%-0.7% of emergency surgical resections because of suspected appendicitis which is usually the first manifestation of ANET. Although there are a lot of papers about application of somatostatin receptor scintigraphy in gastrointestinal neuroendocrine tumors, there are very rare sporadic cases described about ANETs particularly.

AIM

To establish the role of somatostatin receptor scintigraphy (SRS) in the management of patients with neuroendocrine tumors of appendix (ANET).

METHODS

The total of 35 patients was investigated, 23 females and 12 males, average age (43.7 ± 17.3 years). All patients had histological diagnosis of ANET (34 carcinoids of appendix and one tubular carcinoid). Majority of tumors have been found incidentally during surgery of: Acute appendicitis (n = 15), perforated appendicitis (n = 2), ileus (n = 3), hysterectomy (n = 3), ruptured ovarian cyst (n = 2), caecal volvulus (n = 1), while 9 patients had diagnosis of appendiceal tumor before the surgery. Seventeen patients had tumor grade (G) G1, 12 G2 and 6 G3. The right hemicolectomy was performed in 13, while the rest of the patients had appendectomy only. SRS was done early (2 h) and late (24 h) after i.v. application of 740 MBq technetium-99m ethylenediamine-N, N'-diacetic acid Hydrazinonicotinyl-Tyr3-Octreotide (technetium-99m-Tektrotyd, Polatom, Poland). SRS was performed for restaging in all the patients after surgery.

RESULTS

There were 12 true positive (TP), 19 true negative, 3 false positive and 1 false negative SRS result. Sensitivity of the method was 92.31%, specificity was 86.36%, positive predictive value was 80.00%, negative predictive value was 95.00% and accuracy 88.57%. Receiver operating characteristics analysis showed that SRS scintigraphy is a good test for detection TP cases [area under the curve of 0.850, 95% confidence interval (CI): 0.710-0.990, P < 001]. Single photon emission computed tomography contributed diagnosis in 7 TP findings. In 10 patients Krenning score was 4 and in 2 was 3. In 8 patients SRS significantly changed the management of the patients (in two surgery was repeated, in 4 somatostatin analogues and in two peptide receptor radionuclide therapy). Median progression-free survival in SRS positive patients was 52 months (95%CI: 39.7-117.3 mo) while in SRS negative patients it was 60 months (95%CI: 42.8-77.1 mo), without statistically significant difference between the two groups (P = 0.434).

CONCLUSION

In conclusion, our results confirmed the value of SRS in the follow-up of the patients with ANET after surgery, if recurrences or metastases are suspected.

Imaging Bacteria with Radiolabelled Probes: Is It Feasible?

Bacterial infections are the main cause of patient morbidity and mortality worldwide. Diagnosis can be difficult and delayed as well as the identification of the etiological pathogen, necessary for a tailored antibiotic therapy. Several non-invasive diagnostic procedures are available, all with pros and cons. Molecular nuclear medicine has highly contributed in this field by proposing several different radiopharmaceuticals (antimicrobial peptides, leukocytes, cytokines, antibiotics, sugars, etc.) but none proved to be highly specific for bacteria, although many agents in development look promising. Indeed, factors including the number and strain of bacteria, the infection site, and the host condition, may affect the specificity of the tested radiopharmaceuticals. At the Third European Congress on Infection/Inflammation Imaging, a round table discussion was dedicated to debate the pros and cons of different radiopharmaceuticals for imaging bacteria with the final goal to find a consensus on the most relevant research steps that should be fulfilled when testing a new probe, based on experience and cumulative published evidence.

Prospective study on diagnostic and prognostic significance of postoperative FDG PET/CT in recurrent colorectal carcinoma patients: comparison with MRI and tumor markers

Current guidelines for follow-up after resection of colorectal cancer (CRC) recommend regular measurements of carcinoembryogenic antigen (CEA) and imaging tests. Multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) are currently primary imaging modalities, while the role of fluorine-18-fluoro-deoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT), which is recommended in patients with negative MDCT and increased CEA, is still uncertain. Our aim was to compare diagnostic performance and prognostic significance of 18F-FDG PET/CT with MRI and tumor markers CEA and carbohydrate antigen 19-9 (CA 19-9) in detection of recurrent CRC. This prospective study included 35 patients with resected CRC, referred to 18F-FDG PET/CT examination for suspected recurrence. During median follow-up of 24.4±1.5 months 18F-FDG PET/CT and MRI results and tumor marker levels were compared with findings of histopathological examination or with results of clinical and imaging follow-up. Management plan before the 18F-FDG PET/CT scan was considered and compared to the final treatment decision. The sensitivity, specificity, positive and negative predictive value and accuracy of 18F-FDG PET/CT and MRI in detection of recurrent colorectal cancer in patient-based analysis were 92.6%, 75%, 92.6%, 75% and 88.6%, and 65.4%, 66.7%, 85%, 40% and 65.7%, respectively. In lesion-based analysis the sensitivity of 18F-FDG PET/CT and MRI was 83.1% and 68.2%, respectively. The overall accuracy of CEA and CA 19-9 in recurrence detection was 48.6% and 54.3%, respectively. PET/CT induced therapy alterations in 13/35 (37.1%) patients. Progression was observed in 16/35 patients during follow-up, with significantly lower risk of progression in patients with treatment changes based on PET findings (Multivariate Cox regression; p=0.017). In addition, elevated CA 19-9 levels in time of PET scan and male gender carried significantly higher risk of progression (p=0.007 and p=0.016, respectively). Kaplan-Meier Log rank test showed significantly longer progression-free survival time in patients who had treatment plan changed based on PET/CT (p=0.046). We can conclude that 18F-FDG PET/CT showed better sensitivity and accuracy compared to MRI in detection of recurrent colorectal cancer, with much better sensitivity compared to CEA and CA 19-9. Patients with treatment changes based on 18F-FDG PET/CT had significantly better prognosis and longer progression-free survival, while elevated values of CA 19-9 and male gender were associated with worse prognosis.

The detection of endocarditis, post implantation grafts, arteritis and other related disorders by 18F-FDG PET/CT

INTRODUCTION

Positron emission tomography with computed tomography (¹⁸F-FDG PET/CT) is a nuclear medicine diagnostic method which, unlike other technological modalities that asses anatomical features, detects increased glucose metabolism inside the cells, thus is very helpful in diagnosing cardiovascular infection and inflammation and also in therapy planning.

AIM

Aim of this study was to assess the significance of ¹⁸F-FDG PET/CT in detection of an active disease in patients with infection and inflammation of cardiovascular system.

MATERIAL AND METHODS

In this cohort retrospective study 73 cardiovascular patients (56.9±15.3 years; 33 male and 40 female) with persistent symptoms of inflammatory syndrome were referred to ¹⁸F-FDG PET/CT in order to evaluate active disease. Biochemical blood analyses (erytrocite sedimentation, CRP, leukocytic formula), CT, MRI, ultrasound were performed in all the patients. Out of 73 patients, 7 had a second ¹⁸F-FDG PET/CT examination (62.1±12.3 years; 6 men and 1 woman) with a previous pathological PET/CT finding after which the therapy was changed. The degree of metabolic activity was analyzed visually and quantitatively using the maximal standardized uptake value (SUV_max). ¹⁸F-FDG PET/CT findings were considered positive in case of higher focal glucose accumulation in projection of heart and diffuse uptake in blood vessels' wall than accumulation in surrounding tissue and liver.

RESULTS

Vasculitis was diagnosed in 36 patients (49,3%), endocarditis in 23 (31,5%) and graft inflammation in 14 (19,2%). The results were compared to the gold standard, biopsy of the blood vessel and histopathological verification during surgical treatment, or clinical follow up. Forty nine patients with the sights of an increased FDG uptake were considered true positive (TP) (SUV_max5.7±2.9). In 21 patients ¹⁸F-FDG uptake was physiological and they were considered true negative (ТN). Two who used corticosteroid therapy which decreases inflammation, were false negative (FN), and only 1 false positive (FP) finding in the region of recent iatrogenic vein injury. Sensitivity of this method was 96.08±, specificity 95.45±, positive predictive value 98.0±, negative predictive value 91.3± and accuracy 95.89±.

CONCLUSION

Our results indicate that ¹⁸F-FDG PET/CT could be useful diagnostic method for the detection of sights of metabolically active disease in patients with persistent symptoms of infection and inflammation of cardiovascular system, as well as in monitoring therapy response.

Diuresis renography and ultrasonography in children with antenatally detected hydronephrosis can support diagnoses and suggest related surgery treatment

OBJECTIVE

Prenatal ultrasound (US) screening detects the hydronephrosis (HN)-dilatation of fetal renal collecting system in 1%-5% of all pregnancies. In most children, HN is detected by prenatal US screening between 18-20 gestational week. Pelvi- ureteric junction (PUJ) stenosis is the most common etiological factor of prenatal HN and requires postnatal follow-up. Diuresis renography plays important role in the follow-up by complementing morphological information obtained by US with the data about differential renal function (DRF) and drainage. We studied the association between ultrasound parameters and results of diuresis renography in first diagnosed PUJ stenosis and the predictive factors of pyeloplasty in order to evaluate the usefulness of diuresis renography in these children postnatally.

PATIENTS AND METHODS

Children with antenatally detected HN attributed to presumed PUJ stenosis were investigated with mercapto-acetyltriglycine (MAG₃) diuresis renography. Parents gave informed consent for the procedure. The inclusion criteria were: age up to 4 years, diagnosis of prenatal HN determined by US during pregnancy based on the antero-posterior diameter (APD) of renal pyelon and at least one post-natal US which confirmed diagnosis. Exclusion criteria were: APD of pyelon <10mm, previous surgical treatment of HN, vesicoureteral reflux excluded by micturating cystourethrography, and patients having any anomaly of the contralateral kidney. Sixty two patients 43 boys, 19 girls, median age 16 months were selected. They were divided into three groups based on the size of pyelon, three groups based on the calyceal size and two groups according to thickness of parenchyma. Renography was performed for 24 minutes after the iv. application of ^99mTc MAG₃, 144 ten-sec images were applied. Furosemide was administered after 2 min. (F+2). Post-void static images were acquired at 60min. The non-commercial software developed by International Atomic Energy Agency was applied to process the studies. The criteria for pathological findings (poor or no drainage) were the renographic curve maintaining a plateau, Normalized Residual Activity (NORA) at 20. min.>1.62, Output efficiency (OE) at 20. min.<71%, postmicturating NORA >0.11. The DRF was considered normal within the range of 45%-55%.

RESULTS

Good drainage had 74% of children, partial drainage 11%, and poor 15%. There was a clear association between the size of pyelon, calyces, parenchyma thickness and drainage. There was also a clear association between the calyceal size, parenchyma thickness and DRF. Differential renal function was <45% in 18% of children. A relation between the type of drainage and DRF was not determined. Thus, 66.7% of those with poor drainage had preserved DRF. Seven out of nine children with poor drainage underwent pyeloplasty. The threshold for pyeloplasty was the pyelon of 18mm and calyces of 10mm. The model of the multivariate logistic regression which included ultrasound parameters (APD of pyelon, calyces size and parenchymal thickness), drainage and DRF, which were significant predictors in univariate analysis, showed that only drainage was an independent predictor for the need of pyeloplasty.

CONCLUSION

Antero-posterior diameter of the pyelon <15mm indicates a favorable course of congenital HN in most children. Pattern of drainage obtained by diuresis renography was the only independent predictor for the need of pyeloplasty.

Evaluation of neuroendocrine tumors with 99mTc-EDDA/HYNIC TOC

BACKGROUND

This paper is the short review of our preliminary results obtained with 99mTc-EDDA/HYNIC-TOC.

MATERIAL AND METHODS

The total of 495 patients with different neuroendocrine tumors were investigated during last few years.

RESULTS

There have been 334 true positive (TP), 73 true negative (TN), 6 false positive (FP) and 82 false negative findings (FN). Diagnosis was made according to SPECT findings in 122 patients (25%). The mean T/NT ratio for TP cases was significantly higher (p < 0.01) on SPECT (3.12 ± 1.13) than on whole body scan (2.2 ± 0.75). According to our results, overall sensitivity of the method is 80%, specificity 92%, positive predictive value 98%, negative predictive value 47% and accuracy 82%. Fifteen TP patients underwent therapy with 90Y-DOTATATE.

CONCLUSION

Scintigraphy of neuroendocrine tumors with 99mTc-Tektrotyd is a useful method for diagnosis, staging and follow up of the patients suspected to have neuroendocrine tumors. SPECT had important role in diagnosis. It is also helpful in the appropriate choice of the therapy, including the peptide receptor radionuclide therapy. In the absence of 68Ga-labeled peptides and PET/CT, the special emphasize should be given to application of SPECT/CT as well as to the radioguided surgery.

FDG PET/CT in bone sarcoidosis

BACKGROUND

Bone sarcoidosis is rare manifestation of disease usually accompanied with pulmonary involvement. Until today, exact prevalence of bone sarcoidosis is not known, since reported prevalence varies widely depending on the studied population and the used diagnostic techniques.

OBJECTIVE

To determine the prevalence of bone involvement and distribution pattern in active chronic sarcoidosis by using FDG PET/CT.

METHODS

Between January 2010 and December 2011, 98 patients with chronic sarcoidosis and presence of prolonged symptoms or other findings suggestive of active disease were referred to FDG PET/CT examination. Active disease was found in 82 patients, and they all were screened for presence of bone sarcoidosis on FDG PET/CT. All patients also underwent MDCT and assessment of serum ACE level.

RESULTS

Bone sarcoidosis was present in 18/82 patients with active sarcoidosis. FDG uptake in bones was focal in 8 (44.4%), diffuse in 6 (33.3%) and both diffuse and focal in 4 (22.2%) patients. CT indicated bone abnormalities only in 5% patients. Osseous involvement was present in: pelvis (61.1%), vertebrae (44.4%), ribs (27.8%) and bone marrow (16.7%). Some patients had two or more locations of disease. Follow-up FDG PET/CT showed normal findings in two patients, same localization of active disease in four patients and progression of disease in one.

CONCLUSION

In patients with active chronic sarcoidosis 22% of patients had osseous abnormalities on FDG PET/CT that mostly were not detected on CT.

Metabolic activity of breast cancer metastatic lesions on positron emission tomography/computed tomography: comparison with histological and biological characteristics of primary tumor

Higher intensity of FDG uptake on PET/CT in primary tumor is seen in patients with IDC compared to ILC, also in high grade tumours, tumours with negative ER and higher Ki67 values, while data are inconsistent in case of relation between primary tumor's PgR and HER2 expression with its metabolic activity levels. On account of the lack of studies that include research of breast cancer metastatic lesion metabolism level and its relation to tumor histology and biology, our goal was to investigate the association of metastatic lesions' glucose metabolism level on PET/CT with different histological and biological characteristics of primary tumor. In a total number of N=100 patients, highest SUVmax values for each patient were used in testing difference between metastatic metabolic activity in patients with different tumor histology, grade, ER, PgR and HER2 status, subtype, as well in testing relation of Ki67 index to metastasis' metabolism level. In testing difference between histological types of breast cancer, SUVmax values were also compared separately for each specific anatomical site (regional and distant lymph nodes, bones and liver). No difference was found regarding metastatic SUVmax values in patients with primary IDC (n=55, median SUVmax 9.70) and ILC (n=34, median SUVmax 7.20) independently of anatomic site, and for each of analysed sites separately. No difference was found as well between SUVmax detected in metastasis in patients with different grade (grade II: n=58, median SUVmax 7.70; grade III: n=12, median SUVmax 10.20), ER (59 positive, median SUVmax 8.50; 22 negative, median SUVmax 8.05), PgR (55 positive, median SUVmax 8.50; 23 negative, median SUVmax 7.80), and HER2 (14 positive, median SUVmax 6.84; 51 negative, median SUVmax 8.63) expression in primary tumor, and between patients with different tumor subtype. Ki67 was also not associated with tumor metastatic SUVmax values (n=11, rs = -0.21, p=0.53). We conclude that there is no association of primary breast cancer histological type, grade, ER, PgR, HER2 and Ki67 expression with metabolic activity in metastasis detected on PET/CT.

The diagnostic performance and added value of (18)F-FDG PET/CT in the detection of liver metastases in recurrent colorectal carcinoma patients

OBJECTIVE

The aim of this study was to assess the value of (18)F-fluorodeoxyglucose ((18)F-FDG) PET/CT in detection of liver metastases in patients with suspected recurrent colorectal carcinoma, as well as to compare diagnostic performance of (18)F-FDG PET/CT with conventional imaging methods (MDCT).

SUBJECTS AND METHODS

This study included 73 patients with resected primary colorectal adenocarcinoma referred for (18)F-FDG PET/CT to the National PET Center, at the Clinical Center of Serbia, Belgrade, from January 2010 to May 2013, with suspicion of recurrence. The patients underwent (18)F-FDG PET/CT examination on a 64-slice hybrid PET/CT scanner (Biograph, TruePoint64, Siemens Medical Solutions, Inc. USA). Prior to (18)F-FDG PET/CT all patients underwent contrast-enhanced MDCT. Findings of (18)F-FDG PET/CT and MDCT were compared to findings of subsequent histopathological examinations or with results of clinical and imaging follow-up over at least six months. Final diagnosis of liver metastases of colorectal cancer was made either by histopathological examination of specimen after biopsy or surgery, or based on clinical, laboratory and imaging evaluation during first six months after PET/CT scan.

RESULTS

In detection of liver metastases (18)F-FDG PET/CT showed sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 83.3%, 95.3%, 92.6%, 89.1% and 90.4%, respectively. In addition, MDCT showed sensitivity, specificity, positive predictive value, negative predictive value and accuracy in detection of liver metastases of 60%, 88.4%, 78.3%, 76% and 76.7%, respectively. There was significant difference in sensitivity (83.3% vs 60%; P=0.045) between these two methods. In addition, significant difference was observed in accuracy between PET/CT and MDCT (90.4% vs 76.7%; P=0.016). The higher specificity in visualization of liver metastases was also achieved by (18)F-FDG PET/CT compared to MDCT (95.3% vs 88.4%), but this difference was not significant (P=0.37).

CONCLUSION

(18)F-FDG PET/CT was highly sensitive, specific and accurate method in detection of liver metastases in patients with suspected recurrent colorectal carcinoma in our study. This hybrid imaging showed superior diagnostic performance in evaluation of suspected colorectal cancer liver metastases compared to conventional imaging.

Comparison of 18F-FDG PET/CT and MDCT for staging/restaging of non-small cell lung cancer

Multi-detector computed tomography (MDCT) is most commonly used for staging of non-small cell lung cancer (NSCLC). In recent years, 18F- fluorodeoxyglucose positron emission tomography combined with computed tomography (18F-FDG PET/CT) has also been used for the same purpose. Since studies comparing these two methods are scarce, our aim was to determine how the TNM classification and thereby staging of NSCLC compare between 18F-FDG PET/CT and MDCT. 18F-FDG PET/CT and MDCT were collected in 83 patients with NSCLC 3 to 30 days apart (median 17 days). The investigators interpreting 18F-FDG PET/CT were unaware of MDCT results. The Cohen's kappa (κ) was calculated to determine the rate of agreement. The hypothesis was that the strength of agreement between the two methods will be at least moderate (κ>0.40) based on the adopted criteria (κ<0.20 poor; 0.21-0.40 fair; 0.41-0.60 moderate; 0.61-0.80 good; 0.81-1.00 very good agreement). The agreement was moderate for determining the T class (κ=0.45, overall agreement 58%), poor for the N class (κ=0.13, 42%) and fair for the M class (κ=0.22, 58%). The agreement for overall staging of NSCLC was poor (κ=0.20, 45%). The major source of disagreement was that metastases were present more frequently and/or in larger number on 18F-FDG PET/CT than MDCT in the contralateral mediastinal, supraclavicular, and distant lymph nodes, as well as in the bones and suprarenal glands. Since 18F-FDG PET/CT detected more regional and distant metastases than MDCT, we conclude that FDG PET/CT is useful for staging/restaging and planning treatment of patients with NSCLC.

KEYWORDS

Non-small cell lung cancer, positron emission tomography, multidetector computed tomography, metastases detection.

Evaluation of the SIOPEN semi-quantitative scoring system in planar simpatico-adrenal MIBG scintigraphy in children with neuroblastoma

Neuroblastoma is the most common malignancy in children comprising 7.6% of all infantile cancers. MIBG scintigraphy is a mandatory neuroblastoma diagnostic test, which is among others methods, semi-quantified by the SIOPEN method. The aim of this study was to test both the skeletal and the soft tissue segments of the SIOPEN scoring method in the diagnostic milieu and to correlate them with the Curie score. Since there is little knowledge of their diagnostic power, the following variables were tested: VMA, HVA, LDH, and MYCN, ferritin, bone marrow infiltration, the INSS and the INPC classification. The cross-sectional study with repeated measurements of 143 scintigrams was performed on 76 pediatric patients with suspected or proven neuroblastoma, who had been referred to the Center for Nuclear Medicine of the Clinical Center of Serbia in the period 2007-2012. The range of the SIOPEN soft tissue scores was 0-5. The range of the SIOPEN skeletal scores was 0-57. The range of the Curie scores was 0-26. The skeletal SIOPEN scores were significantly higher in bone marrow positive children, in children with pathologically elevated urinary VMA levels and in children having a more advanced clinical stage. There was no difference in the SIOPEN soft tissue score due to higher VMA levels, or depending on the clinical stage and positive bone marrow assessment. There was no difference between the SIOPEN skeletal and soft tissue scores on one hand and the histological grade of the tumor; elevated or normal levels of HVA, LDH, NSE and ferritin, or the presence or absence of MYNC amplification in the neuroblastoma cell line, on the other hand. The results of both SIOPEN scores showed a high linear correlation with the Curie score. The conclusion is that the soft tissue segment of the SIOPEN score needs further elucidation in a more controlled milieu. Excellent correlation between all segments of the two semi-quantitative scoring methods speaks in favor of the application of the complete SIOPEN scoring system in every day mIBG scanning.

Can (18)F-FDG PET/CT scan change treatment planning and be prognostic in recurrent colorectal carcinoma? A prospective and follow-up study

OBJECTIVE

To prospectively study whether in patients with resected primary colorectal cancer fluorine- 18-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) examination could diagnose the stage, specify treatment procedure and be prognostic.

SUBJECTS AND METHODS

This prospective study included 75 patients with resected primary colorectal adenocarcinoma referred for (18)F-FDG PET/CT to the National PET Center, at the Clinical Center of Serbia, Belgrade, from January 2010 to May 2013. Findings of (18)F-FDG PET/CT were compared to findings of subsequent histopathological examinations or with results of clinical and imaging follow-up. Patients were followed after PET/CT examination for a mean follow-up time of 16.7±5.9 months.

RESULTS

In the detection of recurrent disease (18)F-FDG PET/CT showed overall sensitivity, specificity, PPV, NPV and accuracy of 96.6%, 82.4%, 94.9%, 87.5% and 93.3%, respectively. In the detection of stages I and II sensitivity, specificity and accuracy of (18)F-FDG PET/CT were: 88%, 96.6% and 94.7%, respectively, and in the detection of stages III and IV sensitivity, specificity and accuracy were 94.9%, 87.5% and 93.3%, respectively. These findings prevented or changed intended surgical treatment in 12/32 cases. Univariate and multivariate Cox proportional regression analyses revealed that metastatic recurrence (stages III and IV) was the only and independent prognostic factor of disease progression during follow-up (P=0.012 and P=0.023, respectively). Although, survival seemed better in patients with local recurrence compared to metastatic recurrent disease, this difference did not reach significance (Log-rank test; P=0.324). In addition, progression-free survival time was significantly longer in patients in whom (18)F-FDG PET/CT scan led to treatment changes (Log-rank test; P=0.037).

CONCLUSION

(18)F-FDG PET/CT was sensitive and accurate for the detection and staging of local and metastatic recurrent colorectal carcinoma, with higher specificity in the detection of local recurrences. The (18)F-FDG PET/CT scan induced treatment changes in 30/75 patients, including 12/32 patients in which surgical treatment was previously planned, and progression free survival time was significantly longer in these patients.

FDG PET imaging in sarcoidosis

The objective of this review is to highlight the clinical utility of FDG-PET/CT for evaluation of patients with chronic sarcoidosis. The emphasis was on the potential advantages and disadvantages of this technique in these patients based on which recommendations were made. The advantage of FDG-PET/CT technique is that it can visualize FDG accumulation in activated inflammatory cells and simultaneously provide PET and CT images. Of particular interest is the use of FDG-PET/CT for the staging and identification of occult sites and sites suitable for biopsy and for the assessment of inflammatory active sarcoidosis in patients with prolonged symptoms, especially when other markers of the disease are within normal values. FDG-PET/CT also provides a better visualization of extrathoracic sites of active sarcoidosis, such as in the bones, liver, spleen, and retroperitoneal lymph nodes. The use of FDG-PET/CT is of special interest in cardiac sarcoidosis because this potentially life-threatening disease is sometimes present in asymptomatic patients. FDG-PET/CT also has a role in the clinical management of patients with chronic persistent sarcoidosis, such as for planning treatment, monitoring response, and long-term follow-up. The limitations of FDG-PET/CT in patients with sarcoidosis are discussed in the context of a "sarcoidosis-lymphoma syndrome" and potentially excessive radiation exposure. Further prospective multicentre studies are needed to refine the clinical applications of FDG-PET/CT in patients with sarcoidosis and drive the field forward.

Clinical value of immunoscintigraphy in the rectal carcinomas: immunoscintigraphy of rectal carcinomas

BACKGROUND/AIM

The aim of this study was to evaluate the clinical reliability of the immunoscintigraphy with radiolabeled monoclonal antibodies for the detection of metastases and recurrences of rectal carcinomas.

METHODOLOGY

A total of 65 patients underwent immunoscintigraphy with radiolabeled monoclonal antibodies. Indication for that examination was suspicious rectal cancer or suspicious rectal cancer recurrence and/or metastases.

RESULTS

The method proved to have 92.7% sensitivity, specificity 83.3%, positive predictive value 90.5%, negative predictive value 87.0% and accuracy 89.2%. There was a statistically significant relationship between immunoscintigraphy findings and rectoscopy findings (rs=0.415, p=0.013), as well as significant relationship between immunoscintigraphy findings and US findings (rs=0.332, p=0.001). Tumor marker levels were in positive correlation with findings of immunoscintigraphy (rs=0.845, p=0.001), especially raised CEA level (rs=0.816, p=0.004). Patients with higher CA19-9 level had higher Duke's stage (p=0.025).

CONCLUSIONS

We can conclude that immunoscintigraphy can be helpful in the detection of metastases and recurrences of colon carcinomas.

Clinical outcome of early glottic carcinoma in Serbia

OBJECTIVE

Proposed methods for treating early glottic carcinoma are cordectomy through laryngofissure, laser cordectomy, and radiotherapy. The aim of the study was to conduct comprehensive study to evaluate oncological and functional results of different treatment modalities for Tis and T1 glottic carcinoma, identify prognostic factors for the outcome of treatment and decide where we stand in applying worldwide standards of early glottic carcinoma treatment.

METHODS

Prospective study was conducted on 221 patients treated with Tis and T1 glottic carcinoma from 1998 to 2003 (72 patients were treated endoscopically with CO2 laser, 75 patients with cordectomy through laryngofissure and 74 with radiotherapy), with follow-up period from 38 to 107 months. Important demographic and clinical variables were analyzed. Voice quality after the treatment was assessed using multidimensional voice analysis.

RESULTS

Comparing oncological results of three modalities of treatment, there were no significant differences. Functional results of treatment were better after laser cordectomy and primary radiotherapy than following the open cordectomy. Five-year survival rate was almost identical in all three groups of patients, and important prognostic factors for survival were age and histological grade of the tumor.

CONCLUSION

Considering that the choice of treatment in our country is also greatly influenced by other paramedical factors, such as distance from treatment facility, reliability of follow-up, significant time delay of radiotherapy because of small number of radiology centers and strong patients' surgeon and treatment preference, we consider endoscopic laser surgery highly efficient and preferred choice of treatment for early glottic carcinoma.

The clinical value of scintigraphy of neuroendocrine tumors using (99m)Tc-HYNIC-TOC

PURPOSE

To assess the value of whole body scintigraphy using (99m)Tc-HYNIC-TOC (Tektrotyd) and with single photon emission computerized tomography (SPECT) in the detection of primary and metastatic neuroendocrine tumors (NETs).

METHODS

Thirty patients with different neuroendocrine tumors, mainly gastroenteropancreatic (GEP), were investigated. Whole body scintigraphy was performed 2 h (if necessary 10 min and 24h) after i.v. administration of 740 Mbq (99m)Tc-Tektrotyd, Polatom. In cases of unclear findings obtained by whole body scintigraphy, investigation was followed by SPECT.

RESULTS

From 12 patients with NETs of unknown origin, there were 10 true positive (TP), and 2 false negative (FN) findings. Diagnosis was made with SPECT in 6 patients. From 8 patients with gut carcinoids, there were 4 TP, 2 true negative (TN), one FN, and one false positive (FP) finding. Diagnosis was made with SPECT in 2 patients. From 7 patients with neuroendocrine pancreatic carcinomas there were 4 TP and 3 TN findings. Diagnosis was made with SPECT in 2 patients. From 3 patients with gastrinomas there were 2 TP findings and one TN findings. Diagnosis was made with SPECT findings in 2 patients. Sensitivity of (99m)Tc-HYNIC-TOC was 87%, specificity 86%, positive predictive value 95%, negative predictive value 67% and accuracy 87%.

CONCLUSION

We concluded that scintigraphy with (99m)Tc-Tektrotyd is an useful method for diagnosis, staging and follow up of the patients with NETs.

Estimation of infarct size using transthoracic Doppler echocardiographic measurement of coronary flow reserve in infarct related and reference coronary artery

BACKGROUND

Patients in chronic phase of myocardial infarction (MI) have decreased coronary flow reserve (CFR) in infarct related artery (IRA) that is proportional to the extent of microvascular/myocardial damage. We proposed a novel model for the assessment of microvascular damage and infarct size using Doppler echocardiography evaluation of CFRs of the IRA (LAD) and reference artery (RCA).

METHODS

Our study included 34 consecutive patients (28 men, mean age 50 ± 11 years) with first anterior STEMI and single vessel disease successfully treated with primary PCI. All patients underwent SPECT MPI for the assessment of infarct size (expressed as a percentage of myocardium with fixed perfusion abnormalities) and CFR evaluation of LAD and RCA. CFR derived percentage of microvascular damage (CFR PMD) was calculated as: CFR PMD=(CFR RCA-CFR LAD)/(CFR RCA-1)×100 (%).

RESULTS

CFR PMD correlated significantly with all parameters evaluating the severity of myocardial damage including: peak CK activity (r=0.632, p<0.001), WMSI (r=0.857, p<0.001), ejection fraction (r=-0.820, p<0.001), left ventricular end diastolic (r=0.757, p<0.001) and end systolic volume (r=0.794, p<0.001). Most importantly, CFR PMD (22 ± 17%) correlated significantly with infarct size by SPECT MPI (21 ± 17%) (r=0.874, p<0.001).

CONCLUSIONS

CFR PMD derived from the proposed model was significantly related to echocardiographic and enzymatic parameters of infarct size, as well as to myocardial damage assessed by SPECT MPI in patients with successfully reperfused first anterior STEMI.

Scintigraphic detection of colon carcinomas with iodinated monoclonal antibodies

PURPOSE

The aim of this study was to evaluate the clinical reliability of the immunoscintigraphy with iodinated monoclonal antibodies for the detection of metastases and recurrences of colon carcinomas.

METHODS

A total of 45 patients with colon carcinoma was investigated with gamma camera, after intravenous application of iodinated monoclonal antibodies.

RESULTS

The sensitivity of the method was 90%, specificity 86%, positive predictive value 93%, negative predictive value 80% and accuracy 87%. There was statistically significant relationship between immunoscintigraphic and ultrasonographic (US) findings (p=0.005). Also, there was significant relationship between immunoscintigraphy and Dukes stage (p=0.019). Tumor marker levels were not significantly correlated with immunoscintigraphic findings (p<0.05). Significant difference was noted in patients with positive findings for malignancy on US and immunoscintigraphic findings (p=0.006), i.e. patients with positive findings for malignancy had more frequently immunoscintigraphic findings of malignancy. Correlation with other diagnostic procedures (rectoscopy, colonoscopy, CT) did not show significant correlations.

CONCLUSION

We conclude that immunoscintigraphy can be helpful in the detection of metastases and recurrences of colon carcinomas.

The utility of 18F-FDG PET/CT for diagnosis and adjustment of therapy in patients with active chronic sarcoidosis

The purpose of this study was to assess the utility of (18)F-FDG PET/CT for detection of inflammation in granulomatous sites and management of patients with chronic sarcoidosis. The 3 specific aims were to assess differences between (18)F-FDG PET/CT and multidetector CT (MDCT) findings, to compare (18)F-FDG PET/CT results with serum levels of angiotensin-converting enzyme (ACE), and to determine whether (18)F-FDG PET/CT findings are associated with the decision to change therapy.

METHODS

We studied 90 sarcoidosis patients (mean age ± SD, 47 ± 12 y; 32 men and 58 women) with persistent symptoms who were referred for (18)F-FDG PET/CT evaluation to assess the extent of inflammation. They also underwent MDCT and measurement of serum ACE level. After the follow-up (12 ± 5 mo after (18)F-FDG PET/CT), the clinical status and changes in therapy were analyzed.

RESULTS

(18)F-FDG PET/CT detected inflammation in 74 patients (82%) (maximum standardized uptake value, 8.1 ± 3.9). MDCT was positive for sarcoidosis in 6 additional patients (80, 89%). The difference between the 2 methods was not significant (P = 0.238, McNemar test), and their agreement was fair (κ = 0.198). Although ACE levels were significantly higher in patients with positive than negative (18)F-FDG PET/CT results (P = 0.002, Mann-Whitney test), 38 patients (51%) with positive (18)F-FDG PET/CT results had normal ACE levels. The therapy was initiated or changed in 73 out of 90 patients (81%). Both univariate and multivariate logistic regression analyses indicated that positive (18)F-FDG PET/CT results were significantly (P < 0.001) associated with changes in therapy, with no contribution from age, sex, ACE level, CT results, or previous therapy.

CONCLUSION

Our results indicate that (18)F-FDG PET/CT is a useful adjunct to other diagnostic methods for detecting active inflammatory sites in chronic sarcoidosis patients with persistent symptoms, especially those with normal ACE levels. (18)F-FDG PET/CT proved advantageous for determining the spread of active disease throughout the body and influenced the decision to adjust the therapy.

Gallbladder motility disorders estimated by non-invasive methods

BACKGROUND/AIMS

The aim is to compare the radionuclide (DC) and ultrasonographic (US) method in the assessment of gallbladder (GB) motility.

METHODOLOGY

The study was performed in 15 controls (C), 10 patients with acute cholecystitis (AC), 20 patients with chronic acalculous cholecystitis (CAC), 26 patients with chronic cholecystitis with calculosis (CCC) as well as in 15 patients with GB dyskinesia (D). GB emptying period (EP), ejection fraction (EF) and ejection rate (ER) were estimated with dynamic cholescintigraphy (DC) and US.

RESULTS

The DC and US finding in the patients with AC was typical in all the patients, i.e. GB was not visualized at all on DC, while on US, stone was visible in the cystic duct. There were significant differences (p<0.05) between the EF and ER values obtained between C and the three groups of patients CAC, CCC and D, using both methods. However, there were no significant differences in EF, EP and ER values among CAC, CCC and D (p>0.05). There was also high correlation between the results obtained with both methods in all the groups of patients studied.

CONCLUSIONS

The results obtained by both methods are valuable for the assessment of GB motility. Although there are no significant differences and there is a high correlation between the values, radionuclide method is more precise, because it can register motility continuously.

Invasive lobular breast cancer presenting an unusual metastatic pattern in the form of peritoneal and rectal metastases: a case report

Gastrointestinal metastases from invasive lobular breast cancer are uncommon with the stomach and small intestines being the most common metastatic sites. Peritoneal and rectal metastases are very rare and only rarely occur as the first manifestation of disease. We herein report the case of a 47-year-old woman who presented with abdominal carcinomatosis as a first sign of invasive lobular breast carcinoma (ILC). Identifying the most important immunohistochemical markers for ILC: gross cystic disease fluid protein 15, estrogen and progesterone receptors enabled a correct diagnosis. After a six year disease-free period, relapse occurred with severe obstruction due to rectal metastasis from lobular breast carcinoma. Since there was no widespread metastatic disease, surgery with concomitant hormonal therapy was performed.

Diagnosis of mesh infection after abdominal wall hernia surgery - role of radionuclide methods

BACKGROUND/AIMS

The aim of this investigation was to evaluate the role of detection of late mesh infection following incisional hernia repair with radiolabeled antigranulocyte antibodies.

METHODOLOGY

Mesh infection diagnoses were set up with clinical examination and laboratory analysis and confirmed by ultrasonography (US), computerized tomography (CT), scintigraphy with 99mTc-antigranulocyte antibodies and microbiological examination.

RESULTS

Of the 17 patients investigated, 6 had a late mesh infection, and 11 had both mesh infection and recurrent incisional hernia. Clear clinical signs of late mesh infection were present in 13 patients. Four remaining patients had non-specific discomfort and recurrent incisional hernia without clinical manifestation of mesh infection ('silent infection'). US was positive in 12/17 patients, CT in 13/17 patients, while scintigraphy with antigranulocyte antibodies in 17/17 patients. Therefore, sensitivity of US was 71%, of CT 76% and of scintigraphy 100%. In four patients late mesh infection was confirmed exclusively by 99mTc-antigranulocyte antibody scintigraphy, while US and CT did not indicate the infection.

CONCLUSIONS

According to the present results, scintigraphy with 99mTc antigranulocyte antibodies is a useful method for the detection of 'silent' abdominal wall infections after surgery, which is very important for prompt and appropriate therapy.

Monoclonal immunoscintigraphy for detection of metastasis and recurrence of colorectal cancer

AIM: To assess the clinical role of monoclonal immunoscintigraphy for the detection of metastasis and recurrence of colorectal cancer.

METHODS: Monoclonal immunoscintigraphy was performed in patients operated on for colorectal adenocarcinoma suspected of local recurrence and metastatic disease. The results were compared with conventional diagnostics.

RESULTS: Immunoscintigraphic investigation was done in 53 patients. Tumor recurrence occurred in 38 patients, and was confirmed by other diagnostic modalities in 35. In 15 patients, immunoscintigraphic findings were negative, and confirmed in 14 with other diagnostic methods. Comparative analysis confirmed good correlation of immunoscintigraphic findings and the results of conventional diagnostics and the level of tumor marker carcinoembryonic antigen. Statistical analysis of parameters of radiopharmaceutical groups imacis, indimacis and oncoscint presented homogenous characteristics all of three radiopharmaceuticals. The analysis of immunoscintigraphic target focus was clearly improved using tomography.

CONCLUSION: Immunoscintigraphy is highly specific and has a good predictive value in local recurrence of colorectal cancer.

Radioimmunoscintigraphy of colorectal carcinomas with 99mTc-labelled antibodies

BACKGROUND/AIMS

The aim of the study was the evaluation of the clinical validity of immunoscintigraphy with 99mTc labeled antibodies for the detection of metastases and recurrences of colorectal carcinomas.

METHODOLOGY

We examined 17 patients with colorectal carcinomas. Scintigraphy was performed with anti-CEA MoAb 99mTc-BW 431/26.

RESULTS

Recurrences of carcinomas were detected and confirmed by surgery in 6 patients, recurrences with liver metastasis in 5 patients, and only liver metastases in 3 patients. Planar immunoscintigraphy was positive in 5/8 patients with liver metastases and 8/11 patients with recurrences, whereas in 1/8 liver metastases and 3/11 recurrences were detected only by tomography. In two patients with metastases in the abdominal lymph nodes immunoscintigraphic findings both on planar scintigraphy and tomoscintigraphy were false negative.

CONCLUSIONS

Immunoscintigraphy with 99mTc labeled antibodies can be useful in the diagnosis of recurrences and metastases of colorectal carcinoma, viability assessment after radiotherapy and in the choice of the adequate surgical treatment.

Relationship between Helicobacter pylori infection estimated by 14C-urea breath test and gender, blood groups and Rhesus factor

The aim of this study was the detection of helicobacter pylori (HP) infection and estimation of this infection relationship with age, gender, blood groups and Rhesus factor, as well as the assessment of the accuracy of the method. A total of 227 patients with gastritis were examined. Blood ABO groups and Rh positivity were determined using standard tests. Infection by HP was proved by (14)C-urea breath test and gastric biopsy. Patients were aged 20-81 years (X=51.7 years) and the presence of HP was not related to the age (P>0.05). From the total number of patients, 25/69 males and 68/158 females were HP positive. There was no significant difference between genders and HP infection (P>0.05). From the 227 investigated patients, 69 (30%) belonged to blood group O, 96 (42%) to A, 40 (18%) to B and 22 (10%) to AB. HP was detected in 27/69 patients with blood group O, 45/96 patients with blood group A, 16/40 patients with blood group B and 5/22 patients with blood group AB. There was no statistically significant difference (P>0.05) in the incidence of HP infection between these groups (proving that HP infection did not depend upon the blood groups). Also, there was no significant correlation between the presence of particular blood group in HP+ patients related to the reported frequency of the blood groups in Serbian population (0--38%, A--42%, B--15%, AB--5%). HP was found in 16/36 Rh- and in 77/191 Rh+ patients without statistical difference (P>0.05). Also, there was no significant correlation of the presence of the Rh factor in the HP positive patients to the frequency of the Rh factor in the Serbian population (84% Rh+ and 16% Rh-). The basic value of the HP+ test was slightly, but not significantly lower in comparison to the HP- patients (P>0.05). On the contrary, test values showed a highly significant difference (P<0.01) in HP+ and HP- patients. In conclusion, in adults HP infection does not depend upon the patient's age, gender, blood group type or Rh factor. In clinical terms, there were 93 true positive (TP), 129 true negative (TN), 5 false negative (FN) and 0 false positive (FP) patients. Sensitivity of the method was 94.9%, specificity 100%, positive predictive value 100%, negative predictive value 96.3% and accuracy 97.8%.

Is identification of malignant lesions of the liver and of hemangiomas possible by Doppler ultrasonography and radionuclide angiography?

The aim of this study was to try to diagnose malignant liver lesions and hemangiomas by means of vascularisation and perfusion studies. The study was performed in 32 patients with hepatocellular carcinoma (HCC), in 74 with metastatic liver carcinoma (MLC) and in 40 with hemangiomas (H). Color Doppler ultrasonography (DUS) was done with an ATL Ultramark 9 apparatus with convex probe 2.5 MHz using pulse and DUS. Hepatic radionuclide angiography (HRA) was performed with bolus injection of 740 MBq (99m)Tc-pertechnetate, (1 min, 1 f/s), using ROTA scintillation camera and MicroDelta computer. Hepatic perfusion index (HPI) indicated the percentage of the portal blood inflow to the liver. Our results showed that in HCC and MLC there was a decrease of portal inflow while arterial inflow was increased resulting in pulse arterial wave velocity increase and in continuous venous waves velocity in the tumors. There was significant linear correlation between the increase of the arterial inflow and the arterial pulse wave found in the center and in the margin of the tumors. In hemangiomas, hepatic perfusion index related to arterial inflow was within normal range. In conclusion, our results suggest that HCC and MLC have specific characteristics in vascular and/or perfusion studies while hemangiomas show normal liver parenchyma findings.

Detection of gastrointestinal and abdominal infections by 99mTc-antigranulocyte antibodies

BACKGROUND/AIMS

The aim of the study was detection of abdominal infections by 99mTc- antigranulocyte antibodies.

METHODOLOGY

Total of 36 patients with clinical suspicion on abdominal or gastrointestinal infections was investigated.

RESULTS

There were 23 true positive (TP) findings (one pulmonary abscess, 2 subhepatic abscesses after surgery, 2 perianal fistula, 2 chronic and 4 acute appendicitis, 5 abdominal and 3 pelvic abscesses, 3 M. Crohn, one ulcerative colitis), 9 true negative (TN) (3 tumors of the coecum, 2 tumors of papilla Wateri, 2 gastric carcinoma, 2 colon carcinoma), and 4 false negative (FN) (2 abscesses subphrenic and 2 enterocolic fistula). False positive (FP) findings were not observed. The smallest lesion found was 19x18 mm. SPECT increased the number of TP findings from 17 to 23. Fifteen of 23 infectious of inflammatory lesions could be detected in the early scan. Sensitivity was 85%, specificity 100%, positive predictive value 100%, negative predictive value 69% and accuracy 89%.

CONCLUSION

According to the present results, scintigraphy with 99mTc antigranulocyte antibodies is a useful method for detection and assessment of exact localization abdominal infections, which is very important for the prompt and appropriate therapy.

Assessment of non-small cell lung cancer viability and necrosis with three radiopharmaceuticals

Assessment of tumor viability and necrosis of non-small cell lung cancer and detection of distant metastases are important for diagnosis, staging, monitoring the response to treatment and planning long-term management. We performed scintigraphy on patients with non-small cell lung cancer to determine the utility of three tumor targeting tracers for diagnosing primary lung cancer, for differentiating viable from necrotic tumor tissue and for detecting distant bone and soft tissue metastases. Our patients were divided into groups. Group A consisted of 27 patients, 25 male and 2 female, mean age 59 years, range from 35 to 72 years. These patients underwent radioimmunoscintigraphy (RIS) using monoclonal antibody against human milk fat globule labeled with technetium-99m ((99m)Tc). Group B consisted of 23 patients, 21 male and 2 female, mean age 56 years, range: 37 to 70 years. Group C consisted of 24 patients, 20 male and 4 female, mean age 58 years, range: 35 to 74 years. Both Groups B and C underwent chest and whole-body scintigraphy with 555 MBq of (99m)Tc-sestamibi ((99m)Tc-S) and 111 MBq of thallium-201 chloride ((201)TlCl), respectively. Tumor to non-tumor ratio was calculated. Our findings show that RIS had 52% sensitivity in detecting primary non-small cell lung cancer. In contrast, the sensitivity of (99m)Tc-S and of (201)Tl scintigraphy was 87% and 88%, respectively. High uptake of all three radiopharmaceuticals was found in 6 patients with distant soft tissue and bone tissue metastases and in 1 patient with brain metastasis. Mean tumor to non-tumor ratios were similar: for RIS 1.7+/-0.4, for (99m)Tc-S 1.6+/-0.3 and for (201)Tl 1.6+/-0.2.

IN CONCLUSION

(99m)Tc-S and (201)Tl scintigraphy are superior to RIS for detecting non-small primary lung cancers and potentially clinically useful methods for detecting primary lung cancer as above, as well as bone and soft tissue metastases.

Hepatic radionuclide angiography and Doppler ultrasonography in the detection and assessment of vascular disturbances in the portal system

BACKGROUND/AIMS

The aim of the study was evaluation of the morphology of the blood vessels, blood flow velocity and direction with Doppler ultrasound (D-US) and correlation with the relative liver parenchymal perfusion assessed by hepatic radionuclide angiography (HRA).

METHODOLOGY

Real-time, D-US and HRA were performed in 108 patients.

RESULTS

In patients with portal venous aneurysm, hepatopetal blood flow was increased, while portal perfusion did not differ from controls. In portal hypertensive patients, D-US detected dilatation of the portal system veins, with decreased blood flow. In comparison to the portal perfusion in controls and portal venous aneurysm, values were significantly (p < 0.01) lower in chronic active hepatitis and liver cirrhosis and differed between themselves (p < 0.01). In the groups of cirrhotic patients with esophageal varices, sclerosed esophageal varices, recanalized umbilical vein, partial portal thrombosis and cavernous portal vein with hepatofugal, hyperkinetic or slow blood flow, and very low velocities beside the thrombi, portal perfusion was lower (p < 0.01) than in controls, portal venous aneurysm, chronic active hepatitis and liver cirrhosis without collaterals. In complete thrombosis, minimal collateral flow was found with D-US, while HRA proved no portal supply.

CONCLUSIONS

D-US and HRA are complementary for the estimation of various liver vascular disorders.

Littoral-cell angioma as a rare cause of splenomegaly

We report the case of a littoral-cell angioma of the spleen, a recently described benign vascular tumour, whose imaging and pathological characteristics have been discussed only by a few authors. The diagnosis was made after elective splenectomy. The CT images, scintigraphy and histological specimens are presented, and differential diagnoses discussed.

Helicobacter pylori eradication can induce platelet recovery in chronic idiopathic thrombocytopenic purpura

We prospectively investigated the prevalence of Helicobacter pylori (H. pylori) infection in a cohort of 54 adult Serbian patients with chronic idiopathic thrombocytopenic purpura (ITP), and examined the effects of its eradication on their platelet counts. H. pylori infection was diagnosed in 39/54 (72.2%) patients, using the 14C-urea breath test; and was significantly higher than in the healthy Serbian population (55% P < 0.05). H. pylori-positive patients were significantly older than H. pylori-negative patients (P = 0.006), though there were no significant differences regarding gender, disease duration, mean platelet counts, previous therapies and spleen status between H. pylori-positive and H. pylori-negative patients. Successful eradication was confirmed in 23/30 (77%) treated patients. Stable platelet recovery was registered in 6/23 eradicated patients (26.1%) and maintained for 18 months. Complete and partial remissions were achieved in two and four patients, respectively, including one highly refractory patient. A significant mean platelet recovery was seen 6 months after successful H. pylori eradication in the group of 23 patients (P < 0.05). No platelet recovery was registered in either H. pylori-negative (n = 15), untreated H. pylori-positive patients (n = 9) or H. pylori-positive non-eradicated patients (n = 7). Even though the pathogenetic mechanisms of H. pylori-induced thrombocytopenia remain obscure, the results of this small prospective study support the use of H. pylori eradication as an effective non-immunosuppressive treatment for chronic ITP.

Immunoscintigraphy of colorectal carcinomas with radiolabeled monoclonal antibody fragments

BACKGROUND/AIMS

The aim was evaluation of the accuracy and clinical impact of the immunoscintigraphy for the detection of metastases and recurrences of colorectal carcinomas using two different radiolabeled antibody fragments.

METHODOLOGY

The study was performed in 5 patients with IMACIS 1 containing the cocktail of 111MBq 131I MoAb 19-9 F(ab')2 and MoAb anti-CEA F(ab')2 and 8 patients with INDIMACIS 19-9 containing 150MBq of 111In-labeled MoAb 19-9 F(ab')2.

RESULTS

With IMACIS 1, in all the patients, both tumor marker values were elevated. The number of TN was 3/5 and TP 2/5. From 2 TP, one had recurrence of the diseases with peritoneal carcinosis and one with liver metastases. In one patient, the results influenced the therapeutical management. With INDIMACIS 19-9, there were 2/8 TN, with borderline value of CEA and CA 19-9. TP were 6/8 (all with elevated tumor marker values, five of them many times; 3 with recurrences, 1 with recurrence and liver metastases and two with only liver metastases. In three patients, immunoscintigraphy influenced patient management.

CONCLUSIONS

With both radiopharmaceuticals, immunoscintigraphy significantly influenced the patient management or it was complementary. It would be performed in the detection of recurrence, assessment of viability and follow-up of the therapy.

Radioimmunoscintigraphy of colorectal carcinomas with three different radiopharmaceuticals

The aim of the study was evaluation of the clinical reliability of the immunoscintigraphy for the detection of metastases and recurrences of colorectal carcinomas using three different radiopharmaceutical substances. With IMACIS 1, the number of true negative findings (TN) was 4/7 and true positive (TP) 3/7, while in one patient, the results of immunoscintigraphy significantly influenced the therapeutical management. With INDIMACIS 19-9, there were 2/8 TN and 6/8 TP. In three patients, immunoscintigraphy results influenced patient further management. With ONCOSCINT in 2 patients findings were TN, in one FN and in one FP. In 3 patients, immunoscintigraphy influenced the management of the patient. Other imaging methods (CT, US, MRI) have advantage in detection of liver metastases, while immunoscintigraphy is more specific for the assessment of reccurences of the abdominal tumors. Thus immunoscintigraphy should be applied in patients with suggested recurrences and inconclusive outcome of routine diagnostic workup.

Hepatobilijarna scintigrafija u proceni funkcije transplantirane jetre

The aim of the study is evaluation of hepatocellular function, as well as morphology and patency of the biliary three of the liver transplants by dynamic hepatobiliary scintigraphy. The study was performed in 10 controls and 10 patients after orthotopic transplantation (up to two years). Sixty minutes dynamic acquisition (1 frame/min) was performed with scintillation camera after injection of 360 MBq 99mTc-diethyl-IDA. Hepatobiliary scintigrams were analysed for morphology, and parenchymal and hepatobiliary TA curves were generated and analysed as regard to the time to maximal acitivity (Tmax) and the time to half of maximum acitivity (T1/2). Uptake of the radiopharmaceutical was slightly but not significantly delayed (Tmax=18.5+2.9 min) in comparison to the controls (Tmax=14.2+ 3.4min), while excretion was significantly prolonged (T1/2=59.5+ 12.1 min) than physiological (Tmax=34.2+4.1min). Intrahepatic bile flow was nonsignificantly prolonged (Tmax=31.3+3.7 min) in comparison to the controls (Tmax=25.7+ 3.5 min) while extrahepatic one is high significantly prolonged (T1/2=89.0+14.3 min) than physiological (T1/2 =45.0+ 7.2 min). Biliary phase of hepatobiliary scintigraphy showed increased accumulation of radiopharmaceutical in the left (n=1) or right (n=2) hepatic duct. Radionuclide methods are noninvasive, and apear to be sensitive and valuable for the monitoring of liver transplants.

Simultaneous dynamic study of gastric emptying and changes of serum levels of gut hormones in patients after peptic ulcer surgery

BACKGROUND

The aim was to examine the influence of different modalities of peptic ulcer surgery on the gastric emptying (GE) pattern and related serum level changes of selected gut hormones.

MATERIAL AND METHODS

Fifty eight subjects were examined. In 48 of them peptic ulcer surgery was performed at least six months before the examination: Billroth I (B1) in 11, Billroth II (B2) in 16, B1 with the selective vagotomy--Harkins 1 (H1) in 9 and B2 with the selective vagotomy--Harkins 2 (H2) in 12. Ten healthy volunteers (C) were also examined.

RESULTS

The results of gastric emptying showed that the lag phase duration was inversely related to the GE rates, and the GE pattern was linear in both controls (C) and in operated patients, except in B2 group, in which the GE pattern was exponential. In comparison with C group, GE was slower in B1, H1 and H2 groups, and faster in B2 group. The plasma gastrin values in C group, showing two peaks, were higher in relation to other groups. In relation to C group, higher values of motilin were obtained in patients after the selective vagotomy. The plasma somatostatin values recorded in B1 and H1 groups, showing the marked peaks, were higher in relation to C group. In relation to C group the highest plasma neurotensin values were obtained in B2 group.

CONCLUSIONS

In order to understand entirely the influence of peptic ulcer surgery on the GI function, further research of the role of specific hormones and neuropeptides is needed, which would enable more precise selection of the therapy in order to prevent postvagotomy and postgastrectomy syndromes.