The Effects of Breastfeeding and Gestational Diabetes Mellitus on Body Mass Composition and the Levels of Selected Hormones after Childbirth

Breastfeeding may have a positive effect on glucose metabolism and insulin sensitivity, which may reduce the risk of developing diabetes following gestational diabetes mellitus (GDM). This study aimed to evaluate the effect of breastfeeding and GDM on the body mass composition of the studied women, the levels of leptin, ghrelin, adiponectin, resistin, and insulin, and weight loss during the 6-8-week postpartum period and 1 year after childbirth.

MATERIALS AND METHODS

The study group included 42 women with a singleton pregnancy, diagnosed with GDM between the 24th and 28th week of gestation. The control group consisted of 28 non-diabetic women with a singleton pregnancy. This study was carried out at 6-8 weeks as well as at 1 year postpartum. The women were subjected to body weight measurements and body composition analysis performed using a professional body composition analyzer TANITA DC-430 S MA. Waist circumference and subcutaneous fat was measured. Blood for laboratory tests was taken in the morning, on an empty stomach.

RESULTS

It was shown that, regardless of diabetes, exclusive breastfeeding had a significant impact on weight loss at 6-8 weeks postpartum (p = 0.014785) and lower insulin levels (p = 0.047). However, there was no effect of breastfeeding on the women's anthropometric measurements or hormone levels one year after delivery, except for the thickness of subcutaneous adipose tissue, which was significantly lower in breastfeeding women (p = 0.03). One year after delivery, breastfeeding women had a lower BMI (p = 0.0014), less-thick subcutaneous adipose tissue (p < 0.001), and a lower risk of obesity (p = 0.016). There were also higher insulin and ghrelin levels in both breastfeeding and non-breastfeeding women (p < 0.001), and lower resistin levels in non-breastfeeding women (p = 0.004). Women who had diabetes during pregnancy had a significantly reduced waist circumference and subcutaneous fat thickness after one year (p < 0.001 and p = 0.05, respectively).

CONCLUSIONS

Having diabetes during pregnancy did not significantly affect the results of anthropometric measurements and hormone levels noted at 6-8 weeks after delivery (the only exception was the thickness of subcutaneous fat tissue, which was greater in women without GDM). This may indicate normalization of carbohydrate metabolism after childbirth; however, the observation period is too short to elucidate long-term metabolic effects. This suggests the need for further research related to GDM and breastfeeding.

Preoperative Oral Carbohydrate (CHO) Supplementation Is Beneficial for Clinical and Biochemical Outcomes in Patients Undergoing Elective Cesarean Delivery under Spinal Anaesthesia-A Randomized Controlled Trial

BACKGROUND

Preoperative fasting and surgery cause metabolic stress, insulin resistance with ketosis, and postoperative nausea and vomiting (PONV). Oral carbohydrate loading strategy (CHO) improves outcomes in labor and general surgery. We aimed to compare the effectiveness of CHO with standard fasting in patients undergoing elective cesarean delivery (CD) under spinal anesthesia.

METHODS

A single-center, parallel, prospective randomized controlled trial (RCT) was conducted in a tertiary university obstetrics department at Pomeranian Medical University in Szczecin, Poland. Patients were randomly assigned (1:1 ratio) to the CHO group (oral carbohydrate 2 h before elective CD, n = 75) or the SF group (control-standard fasting, n = 73). The main outcome measures were incidence and severity of PONV at 6 and 24 h after CD, time to the first peristalsis, time to first bowel movement, and biochemical parameters indicating ketosis in mothers and their children.

RESULTS

A total of 148 adult females with singleton pregnancies undergoing elective CD under spinal anesthesia (ASA I and II) were included in the final analysis. At 24 h after CD, 8.0% from the CHO group vs. 20.55% reported three or more episodes of vomiting or dry retching as compared to patients in the SF group (p = 0.041). Preoperative CHO supplementation decreased preoperative feelings of hunger (p < 0.001) and thirst (p < 0.001). Laboratory results in the CHO group showed higher plasma pH (p = 0.001) and glucose (p < 0.001), lower F2-isoprostane in plasma (p = 0.049) and urine (p = 0.018), lower urine F2-isoprostane/creatinine ratio (p = 0.045) than in the SF group. HOMA-IR (p < 0.001) and lactate (p < 0.001) were higher in the CHO group than in the control group.

CONCLUSIONS

There was no significant difference in the incidence or severity of early PONV at 6 h. The incidence of vomiting or dry retching at 24 h after cesarean delivery was lower in the CHO group as compared to standard starvation, but the combined results of PONV frequency and severity on the Wengritzky scale did not differ between the two study groups. Preoperative CHO supplementation decreased preoperative feelings of hunger and thirst, enhancing the comfort of pregnant women.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT04069806.

Weight Gain during and after Pregnancy in Women with Gestational Diabetes Mellitus-A Preliminary Study

Appropriate gestational weight gain (GWG) favors fewer complications related to pregnancy, delivery, puerperium, and the condition of the fetus and newborn baby. The aim of this study was to evaluate weight gain in women during and after pregnancy, including both women with and without gestational diabetes mellitus (GDM).

MATERIALS AND METHODS

The study involved 42 singleton pregnant women diagnosed with GDM between the 24th and 28th week of pregnancy. The control group consisted of 28 nondiabetic women with a singleton pregnancy. The pre-pregnancy BMI, intra-pregnancy weight gain, and postpartum body weight were assessed in the participants.

RESULTS

There were no statistically significant differences in the values of intra-pregnancy weight gain. Only diabetic women who were also overweight or obese had a significantly higher percentage of weight gain during pregnancy. The analysis of the percentage of weight gain during the entire pregnancy showed differences only in the group of women with pre-pregnancy BMI over 30.

CONCLUSIONS

There were no significant differences in total pregnancy or mid-pregnancy weight gain between women with and without GDM. Most of the women had too high or too low total-pregnancy and mid-pregnancy weight gain. Therefore it is necessary to control GWG and educate pregnant women about it.

Body Composition and Biological Functioning in Polish Perimenopausal Women with Type 2 Diabetes

BACKGROUND AND OBJECTIVES

The aim was to compare body composition and levels of biochemical blood parameters and identify relationships between biochemical parameters and body composition of women with type 2 diabetes and healthy ones, both in perimenopausal period (172 women aged between 45 and 65 come from the West Pomeranian Voivodeship, Poland).

MATERIALS AND METHODS

The study consisted of an interview, body composition analysis with Jawon Medical IOI-353 (Yuseong, South Korea) analyser and venous blood biochemical analysis (lipid profile, levels of glucose, insulin, CRP, glycated haemoglobin).

RESULTS

The vast majority of body composition measurements varied between study and control groups in a statistically significant way (p < 0.05) except protein and soft lean mass of the torso. Statistically significant differences between the two groups have been observed in case of all biochemical parameters (p < 0.001).

CONCLUSIONS

Body composition of women suffering from type 2 diabetes significantly varied from body composition of healthy women. Results of the first group were characterised by higher values, especially in case of general parameters, abdominal area, content of adipose tissue and soft tissues. Relationship between body composition and biochemical results may be observed, especially in level of triglycerides, CRP and insulin. Higher concentrations of these parameters were associated with increased values of majority of body composition measurements regardless of type 2 diabetes incidence.

MEDICAL STAFF IN THE CARE OF A PREGNANT PATIENT DIAGNOSED WITH FETAL DEFECT

OBJECTIVE

The aim: The research conducted aims at evaluating the way the medical staff functions in the care of the pregnant patient diagnosed with fetal defects.

PATIENTS AND METHODS

Material and methods: 158 midwives took part in the study. The MINI-COPE standardized questionnaire and author's questions were used.

RESULTS

Results: During the period when the care was provided for the pregnant patients diagnosed with fetal defects, nearly 50% of the midwives under examination complained about the decline of their wellbeing. 75,3% of the respondents seek help and advice on how to deal with a stressful situation. Ideal for providing a systemic support, the midwives most often chose a psychologist and a psychotherapist. The surveyed who reported no need for a systemic support for the medical staff at the workplace, as the causes of their attitude pointed to their diminished trust in the ward nurse and no place for honest conversations. Most of the midwives surveyed during the care of the patient with the fetal defects experienced stress and bigger mental exhaustion. Over half of the surveyed reported lack of systemic psychological support provided for the medical staff at the workplace.

CONCLUSION

Conclusions: The research indicates the need to introduce courses and training on topics related to how to deal with stressful situations into the education system of medical staff.

Analysis of the Impact of Type 2 Diabetes on the Psychosocial Functioning and Quality of Life of Perimenopausal Women

Menopause is a natural period resulting from the decrease in hormonal activity of the ovaries. Growing hormonal deficiencies and changes in the body influence a variety of functions in women, leading to depression and decreased quality of life. The relationship between body composition, the severity of depressive and climacteric symptoms and the quality of life of women with type 2 diabetes and healthy women in the perimenopausal period was studied. Statistically significant differences were observed between the study and control groups regarding all body composition parameters except for protein and the content of torso soft tissues (p < 0.05). In both the study and control groups, resulting symptoms were significantly correlated with numerous body composition parameters (e.g., body mass, fat tissue mass, minerals, abdominal circumference), while symptoms of depression were significantly correlated with similar parameters only in the control group. A statistically relevant relationship was observed between the study and control groups with respect to quality of life in certain domains. The quality of life of women suffering from type 2 diabetes was worse compared with healthy women. Analysis of body composition showed significant differences between healthy women and those with type 2 diabetes. Healthy women showed a tendency to establish a link between body composition and depressiveness.

The Relationship between the HLA-G Polymorphism and sHLA-G Levels in Parental Pairs with High-Risk Pregnancy

Human leukocyte antigen G (HLA-G) is observed in immune system cells and other organs. It is a class Ib molecule, which plays a pivotal role in the implantation and maintenance of pregnancy. The aim of this study was to assess the relationship between serum sHLA-G levels and the HLA-G allele in parental pairs with complicated obstetric histories. The clinical material consisted of 210 women and 190 men with the experience of a complicated or an unsuccessful pregnancy. The control group included parents-89 women and 86 men-lacking complicated obstetric histories. We applied genetic analysis methods: isolation of genomic DNA, sequencing, and determination of serum sHLA-G levels. There were no statistically significant differences in the frequencies of the HLA-G -725 C>G polymorphism between particular experimental groups compared with the control group (p > 0.05). The median sHLA-G levels in the women with the HLA-G10101 allele (15.4 U/mL) were significantly higher than in the women with other alleles (p < 0.05). The HLA-G 10101 allele seems to protect against antiphospholipid syndrome, which may be associated with increased serum sHLA-G levels in its carriers. The relationship between serum sHLA-G levels and the HLA-G polymorphisms in the Polish population requires further investigation.

18F-Fluordeoxyglukose PET beim Ovarialkarzinom: Methodik und erste Ergebnisse

Ziel der vorliegenden Studie war die Evaluierung der PET mit 18F-Fluor-deoxyglukose in der Primär- und Rezidivdiagnostik von Ovarialkarzino-men. Methoden: Untersucht wurden 26 Patientinnen mit Verdacht auf primäres Ovarialkarzinom (n = 17) bzw. Rezidiwerdacht (n = 9). Die PET-Untersuchung von Abdomen und Becken erfolgte mit einem ECAT 953/15-Scanner beginnend 45 min nach i.v. Applikation von im Mittel 245 MBq 18FDG. Die PET-Ergebnisse wurden anhand von intraoperativem Befund, Histologie und Zytologie validiert. Ergebnisse: Der richtige Nachweis eines primären, malignen Ovarialtumors bzw. eines Rezidivs gelang in 16 von 19 Fällen, der Malignomausschluß in sechs von sieben Fällen. Falsch negative PET-Befunde wurden bei zwei Borderline-Karzinomen und einem gut differenzierten, serös-muzinösen Ovarialkarzinom erhoben. Ein falsch positiver PET-Befund ergab sich bei einer abszedierenden Salpingoophoritis. Die quantitative Analyse erbrachte einen SUV von 6,8 ± 2,3 für primäre, epitheliale Ovarialkarzinome gegenüber 2,6 ± 1,2 bei benignen, nicht entzündlichen Raumforderungen (p <0,05). Schlußfolgerung: Diese vorläufigen Ergebnisse zeigen, daß PET mit 18FDG zwar geeignet ist zur Rezidivdiagnostik von Ovarialkarzinomen, jedoch limitiert ist in der Differenzierung von Borderline-Karzinomen gegenüber benignen Veränderungen sowie malignen Tumoren des Ovars gegenüber entzündlichen Prozessen. Die quantitative Bildanalyse führt hierbei nicht zu einer Verbesserung der diagnostischen Genauigkeit.

Bestimmung von Einflußgrößen für den Therapieerfolg der Radioiodtherapie bei Patienten mit Morbus Basedow

Ziel der Studie war es, zu prüfen, inwieweit der Erfolg einer Radioiodtherapie (RIT) des Morbus Basedow (MB) von verschiedenen Parametern (Schilddrüsenvolumen [SDVol], Funktion, TRAK, Thyreostase, Therapiedosis, 131l-Uptake, effektive Halbwertszeit) abhängt. Methode: Bei 78 Patienten mit gesichertem MB wurden 626 ± 251 MBq 131 lod oral zur Ablation der Schilddrüse appliziert. 3 Monate nach RIT wurden 60 Patienten kontrolliert. Ergebnisse: Bei Patienten mit einer Hyperthyreose oder TRAK <11 U/l zu Beginn der RIT wurden eine signifikant niedrigere Therapiedosis bzw. Halbwertszeit gefunden als bei nichthyperthyreoten Patienten bzw. Patienten mit TRAK ≤11 U/l. Patienten mit einem SDVol ≤25 ml zeigten signifikant niedrigere 131l-Uptakewerte unter Therapie, jedoch signifikant höhere Relativuptakewerte (131l- Uptake/SDVol) als solche mit SDVol <25 ml. Alle Therapieversager wurden während der RIT thyreostatisch behandelt, sie wiesen im Mittel signifikant niedrigere Therapiedosen und Relativuptakewerte sowie signifikant höhere SdVol als Therapieerfolge auf. Durch die RIT reduzierte sich das SDVol der Patienten um 44%, wobei Versager eine signifikant geringere Volumenreduktion aufwiesen. Patienten mit einer Therapiedosis ≤250 Gy zeigten signifikant schlechtere Therapieresultate als solche mit <250 Gy, nur ein Versager erreichte mehr als 250 Gy, während immerhin 50% der Versager <200 Gy (aber >250 Gy) erreichten. Die Anwendung multivariater Analysen (MANOVA und Faktorenanalysen) ergab die Thyreostase als den entscheidenden Negativfaktor für den Erfolg einer RIT. Schlußfolgerung: Aufgrund der gehäuften Therapieversager bei Patienten mit Thyreostase empfehlen wir daher für diese Patienten eine Erhöhung der Zieldosis auf 250 Gy.

Klinische Wertigkeit der FDG-PET zur Therapiekontrolle bei malignen Lymphomen – Ergebnisse einer retrospektiven Studie an 72 Patienten

Ziel: Retrospektive Validierung der klinischen Wertigkeit von FDG-PET zur Therapiekontrolle bei Patienten mit malignen Lymphomen. Methode: 72 Patienten erhielten nach Therapie eines malignen Lymphoms (41 Non-Hodgkin-Lymphome, 29 Morbus Hodgkin, 2 unklassifiziert) eine statische FDG-PET im Bereich initial befallener Regionen (n = 53) oder von Hals und Körperstamm (n = 19), sowie CT (n = 70) und LDH-Bestimmung im Serum (n = 64). Die Resultate wurden durch Biopsien (n = 7) oder durch den klinischen Verlauf (n = 65) validiert. Die prädiktive Wertigkeit der PET wurde in Abhängigkeit von verschiedenen Risikofaktoren (Stadium, Rezidivstatus und Zahl der applizierten Chemotherapieprotokolle) untersucht. Ergebnisse: Die PET erzielte eine Sensitivität von 88%, eine Spezifität von 83% und eine diagnostische Treffsicherheit von 85% bei der Erkennung residualer Erkrankungsaktivität. Für die CT ergaben sich entsprechend 84%, 31 % und 54%, für die Serum-LDH 50%, 92% und 73%. Der prädiktive Wert der PET war abhängig von der Prävalenz des Rezidivrisikos. Bei Patienten mit mäßigem Risiko (Stadium I—I II, kein Rezidiv, maximal zwei verschiedene Chemotherapieprotokolle) wurde durch ein unauffälliges PET in über 90% eine komplette Remission richtig vorhergesagt, bei Hochrisikopatienten jedoch nur in 50-67%. Schlußfolgerung: Die FDG-PET ist genauer als CT und LDH-Bestimmung zur Therapiekontrolle bei malignen Lymphomen. Bei Patienten mit mäßig hohem Rezidivrisiko kann der Therapieerfolg zuverlässig vorhergesagt werden.

Altered Relationships Between rCBF in Different Brain Regions of Never-Treated Schizophrenics

Aim of this study was to investigate the relations between regiona cerebral blood flow (rCBF) of different brain regions in acute schizophrenia and following neuroleptic treatment.

Methods: Twenty-two never-treated, acute schizophrenic patients were examined with HMPAO brain SPECT and assessed psychopathological-ly, and reexamined following neuroleptic treatment (over 96.8 days) and psychopathological remission. rCBF was determined by region/cerebel-lar count quotients obtained from 98 irregular regions of interest (ROIs), summed up to 11 ROIs on each hemisphere. In acute schizophrenics, interregional rCBF correlations of each ROI to every other ROI were compared to the interregional correlations following neuroleptic treatment and to those of controls.

Results: All significant correlations of rCBF ratios of different brain regions were exclusively positive in controls and patients. In controls, all ROIs of one hemisphere except the mesial temporal ROI correlated significantly to its contralateral ROI. Each hemisphere showed significant frontal-temporal correlations, as well as cortical-subcortical and some cortico-limbic. In contrast, in acute schizophrenics nearly every ROI correlated significantly with every other ROI, without a grouping or relation of the rCBF of certain ROIs as in controls. After neuroleptic treatment and clinical improvement, this diffuse pattern of correlations remained.

Conclusions: These results indicate differences in the neuronal interplay between regions in schizophrenic and healthy subjects. In never-treated schizophrenics, diffuse interregional rCBF correlations can be seen as a sign of change and dysfunction of the systems regulating specificity and diversity of the neuronal functions. Neuroleptic therapy and psychopathologic remission showed no normalizing effect on interregional correlations.

One-year Follow-up of Neuropsychology, MRI, rCBF and Glucose Metabolism (rMRGlu) in Cerebral Microangiopathy

Background: MRI shows lacunar infarctions (LI), deep white matter lesions (DWML) and atrophy in cerebral microangiopathy, which is said to lead to vascular dementia. In a first trial series on 57 patients with confirmed pure cerebral microangiopathy (without concomitant macroangiopathy), neuropsychological impairment and (where present) brain atrophy correlated with decreased rCBF and rMRGlu. LI and DWML did not correlate with either neuropsychological impairment or decreased rCBF/rMRGIu. This study was done one year later to detect changes in any of the study parameters. Methods: 26 patients were re-examined for rCBF, rMRGlu, LI, DWML, atrophy and neuropsychological performance (7 cognitive, 3 mnestic, 4 attentiveness tests). Using a special head holder for exact repositioning, rCBF (SPECT) and rMRGlu (PET) were measured and imaged slice by slice. White matter/cortex were quantified using MRI-defined ROIs. Results: After one year the patients did not show significant decreases in rCBF or rMRGlu either in cortex or in white matter (p >0.05), nor did any patient show LI, DWML or atrophy changes on MRI. There were no significant neuropsychological decreases (p >0.05). Conclusions: Cerebral microangiopathy ought to show progressive neuropsychological, functional (rCBF, rMRGlu) and morphological deterioration over periods >1 year. It is unlikely that direct cortical damage (e.g., incomplete infarction) is responsible for neuropsychological impairment since one-year follow-up of our patients revealed no progression of brain atrophy or any other cortical damage.

F-18-FDG Positron Imaging in Oncological Patients: Gamma Camera Coincidence Detection versus Dedicated PET

Aim of the present study was to investigate the feasibility of 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG) imaging in oncological patients with a dual head gamma camera modified for coincidence detection (MCD). Methods: Phantom studies were done to determine lesion detection at various lesion-to-background ratios, system sensitivity and spatial resolution. Thirty-two patients with suspected or known malignant disease were first studied with a dedicated full-ring PET system (DPET) applying measured attenuation correction and subsequently with an MCD system without attenuation correction. MCD images were first interpreted without knowledge of the DPET findings. In a second reading, MCD and DPET were evaluated simultaneously. Results: The phantom studies revealed a comparable spatial resolution for DPET and MCD (5.9 × 6.3 × 4.2 mm vs. 5.9 × 6.5 × 6.0 mm). System sensitivity of MCD was less compared to DPET (91 cps/Bq/ml/cmF0V vs. 231 cps/ Bq/ml/cmFOv). At a lesion-to-background ratio of 4:1, DPET depicted a minimal phantom lesion of 1.0 cm in diameter, MCD a minimal lesion of 1.6 cm. With DPET, a total of 91 lesions in 27 patients were classified as malignant. MCD without knowledge of DPET results revealed increased FDG uptake in all patients with positive DPET findings. MCD detected 72 out of 91 DPET lesions (79.1 %). With knowledge of the DPET findings, 11 additional lesions were detected (+12%). MCD missed lesions in six patients with relevance for staging in two patients. All lesions with a diameter above 18 mm were detected. Conclusion: MCD FDG imaging yielded results comparable to dedicated PET in most patients. However, a considerable number of small lesions clearly detectable with DPET were not detected by MCD alone. Therefore, MCD cannot yet replace dedicated PET in all oncological FDG studies. Further technical refinement of this new method is needed to improve image quality (e.g. attenuation correction).

Concept and validation of a simple model of the intrathyroidal iodine kinetics

Aim of this study is the introduction and validation of a simple model of the intrathyroidal iodine kinetics, designed for optimizing radioiodine therapy planning and dose measurement in a routine clinical setting. Methods: The new model defines the intrathyroidal iodine kinetics as balance of the thyroidal iodine intake and -excretion, characterized by the two exponential equations At = A0 * (1-exp(-λ1t)) and At = A0 * (exp(-λ2t) -1), respectively. A0 describes the theoretically maximum iodine uptake when the thyroidal iodine excretion is ignored, λ1 and λ2 represent the constants characterizing the iodine intake and excretion, respectively. The thyroidal iodine content at the time t equals the sum of both functions, which is At = A0 * (exp(-λ2t)-exp(-λ1t)). In 25 patients with autonomous goiter / nodules (n = 18), Graves’ disease (n = 5), or endemic euthyroid goiter (n = 2), the iodine uptake in the thyroid during the radioiodine therapy as fraction of the applied activity was determined daily, with the remaining body covered by a lead shield. On average, 7.2 measurements were performed per patient (minimum 4, maximum 13). With these uptake values, individual regression curves were fitted using the above equation, and the difference between the actual measurements and the corresponding values of the regression curves was determined.

Results: The average deviation of the 179 uptake values from the calculated points of the respective regression curves was only 1.4%. There was no significant difference between the three disease groups. The distribution of the relative deviations during the individual courses was constant, systematic errors were not detected. Conclusion: Our results suggest that the intrathyroidal iodine kinetics can be precisely described with the model At = A0 * (exp(-λ2t)-exp(-λ1t)). With only three measurements, the trend of the curve can be calculated, which allows to determine the total radioiodine storage in the thyroid.

Spectrometric assessment of thyroid depth within the radioiodine test

Aim of this study is the validation of a simple method for evaluating the depth of the target volume within the radioiodine test by analyzing the emitted iodine-131 energy spectrum. Patients, methods: In a total of 250 patients (102 with a solitary autonomous nodule, 66 with multifocal autonomy, 29 with disseminated autonomy, 46 with Graves’ disease, 6 for reducing goiter volume and 1 with only partly resectable papillary thyroid carcinoma), simultaneous uptake measurements in the Compton scatter (210 ±110 keV) and photopeak (364–45/+55 keV) windows were performed over one minute 24 hours after application of the 3 MBq test dose, with subsequent calculation of the respective count ratios. Measurements with a water-filled plastic neck phantom were carried out to perceive the relationship between these quotients and the average source depth and to get a calibration curve for calculating the depth of the target volume in the 250 patients for comparison with the sonographic reference data. Another calibration curve was obtained by evaluating the results of 125 randomly selected patient measurements to calculate the source depth in the other half of the group. Results: The phantom measurements revealed a highly significant correlation (r = 0,99) between the count ratios and the source depth. Using these calibration data, a good relationship (r = 0,81, average deviation 6 mm corresponding to 22%) between the spectrometric and the sonographic depths was obtained. When using the calibration curve resulting from the 125 patient measurements, the average deviation in the other half of the group was only 3 mm (12%). There was no difference between the disease groups. Conclusion: The described method allows an easy to use depth correction of the uptake measurements providing good results.

Optimizing ventilation-perfusion lung scintigraphy: Parting with planar imaging

Aim of the study was to introduce and verify a ventilation-perfusion (V/Q) acquisition protocol that incorporates new developments in scintigraphy in order to allow for a more balanced comparison with other diagnostic procedures. Methods: In 103 patients suspect of having pulmonary embolism, V/Q scans were acquired exclusively with SPECT technique. Ventilation was done with ultrafine aerosol. Planar images in eight directions were reconstructed through addition of three consecutive SPECT projections. Three referees examined the scans in regard to type, localization, and extent of V/Q defects. Results: Using this protocol, significantly more defects, especially of subsegmental size, were detected (p <0.Q1). Sensitivity, and diagnostic accuracy were also significantly improved (p <0.01) to 0.96, and 0.99, respectively. Furthermore, kappa values were increased up to 0.82 - a relevant enhancement in the ability to precisely localize V/Q defects. Conclusion: In conclusion this protocol provides high-resolution tomographic scans as well as high-quality planar images within a short acquisition time. Due to the significant increase in lesion detection, sensitivity, diagnostic accuracy, and anatomical localization of defects, it is a substantial improvement in the diagnosis of pulmonary embolism that will put V/Q scintigraphy on a par with other tomographic methods.

Combined image interpretation of computed tomography and hybrid PET in head and neck cancer

Aim: Evaluation of potential synergistic effects of combined image interpretation of FDG PET using a gamma camera modified for coincidence detection (hybrid PET) and computed tomography (CT) and comparison of the diagnostic accuracy of hybrid PET and dedicated PET in patients with head and neck cancer. Methods: Forty-two patients with suspected primary or recurrent cancer were included. Twenty-four patients underwent dedicated PET in addition to attenuationcorrected hybrid PET using a one-day protocol. Results: Sensitivity, specificity and accuracy for detection of primary or recurrent head and neck cancer were 74, 73, and 74% for hybrid PET, 52, 82, and 60% for CT and 77, 82, and 79% for combined reading. With the combination of CT and hybrid PET all cases of recurrent disease were detected. The largest tumour not detected was 1.7 cm in diameter. Sensitivity, specificity and accuracy for the detection of neck sides with lymph node metastases were 69, 88, and 85% for hybrid PET, 62, 88, and 84% for CT, 69, 99, and 94% for combined image interpretation. With combined interpretation four involved neck sides were missed including two cases of microscopic metastases. Hybrid PET revealed concordant results to dedicated PET in all patients with respect to the detection of primary or recurrent tumour and in 45 of 48 neck sides (94%) with the same number of false negative findings. Conclusion: The combination of functional information of hybrid PET and morphological information of CT by the simple approach of combined image interpretation improves the sensitivity for the detection of primary/recurrent head and neck cancer and increases the specificity of lymph node staging compared to CT alone. The accuracy of hybrid PET and dedicated PET was almost identical.

Prognostic significance of positron emission tomography using fluorine-18-fluorodeoxyglucose in patients treated for malignant lymphoma

Aim: To evaluate the prognostic significance of positron emission tomography (PET) using fluorine-18-[2]-fluoro-2-deoxyglucose (FDG) in patients treated for Hodgkin’s disease (HD) or nori-Hodgkin’s lymphoma (NHL) compared to conventional restaging (CRS). Methods: Fifty-six patients with either HD (ç = 22), high-grade NHL (n = 26) or centrocyfic-centroblastic NHL (n = 8) were included. PET was performed in 41 patients for treatment reevaluation up to three months after therapy and in patients with persisting residual masses (n = 10) or suspected relapse (n = 5) four to twelve months after treatment. The scans were evaluated qualitatively and quantitatively using standardised uptake values (SUV). Progression-free survival (PFS) was estimated to assess the prognostic value of FDG PET and clinical follow-up was taken as gold standard. Results: PET was positive in nineteen of 41 patients studied for treatment reevaluation. Progression was observed after a median interval of two months (range 0-15) in sixteen of 19 patients after a positive PET scan and in three of 22 patients after a negative scan (p <.001). Median duration of follow-up in progression-free patients was 21 months (range 6-72). In patients with a partial remission in CRS progression was more common in PET-positive than in PET-negative patients (5 of 7 vs. 1 of 14; ñ <.01) and positivity with PET was associated with poorer PFS (p <.0025). PET studies performed four to twelve months after treatment were true negative in seven, true positive in five and false-positive in three patients. SUV > 11.35 of lymphoma lesions was associated with poorer PFS than SUV <11.35 (p <0.025). Conclusion: We conclude that FDG PET after treatment of malignant lymphoma has a high prognostic value and should be recommended in patients with persistence of residual masses.

Characterization of radioiodine therapy failures in Graves’ disease

Aim of this study was a characterization of radioiodine therapy (RIT) failures in Graves’ disease without simultaneous Carbimazole. Method: 226 patients with a confirmed diagnosis of Graves’ disease received 686.8 ± 376.4 MBq of iodine-131 orally for thyroid ablation. Target dose was 250 Gy. All patients were followed up for 6 months. Therapy failures were compared with successes regarding possible influencing variables initial thyroid volume, thyroid function, immune activity (TRAb), 1-131 uptake, effective half-life, absorbed energy dose, age and gender. Results: 212 of 226 patients (93.8%) were treated successfully, 14 (6.2%) showed a hyperthyroidism relapse within 6 months which required a second radioiodine therapy. A success rate of 92.5% (62/67) could also be achieved with 67 patients who were hyperthyroid at the time of RIT. Compared to the therapy successes, the 14 failures achieved significantly lower absorbed doses (223.8 ±76.6 Gyvs. 285.2 ±82.1 Gy, ρ <0.005), but with no significant differences regarding age, thyroid volume, function or TRAb (all ρ >0.2). Of the 14 failures, η = 8 reached an absorbed dose <200 Gy and η = 1 a dose <250 Gy, although 5 of the failures reached an absorbed dose of >250 Gy. Stepwise logistic regression revealed only absorbed energy dose as a variable significantly influencing therapy success (p <0.005), but no influence of initial thyroid volume, function, TRAb value, age (all ρ >0.2) or gender (p = 0.13). Two-tailed Fisher’s exact test showed no significant influence of gender on success rates (failures/successes: male 1 /36, female 13/176, ρ = 0.48). Conclusions: Except for the absorbed energy dose, no other significant variable influencing the outcome of radioiodine therapy in Graves’ disease without simultaneous Carbimazole could be found. It should be noted, though, that 5 therapy failures (2.2%) reached an absorbed energy dose of >250 Gy.

3D volume and SUV analysis of oncological PET studies

Aim: The standardized uptake value (SUV) of 18FDG-PET is an important parameter for therapy monitoring and prognosis of malignant lesions. SUV determination requires delineating the respective volume of interest against surrounding tissue. The present study proposes an automatic image segmentation algorithm for lesion volume and FDG uptake quantitation. Methods: A region growing-based algorithm was developed, which goes through the following steps: 1. Definition of a starting point by the user. 2. Automatic determination of maximum uptake within the lesion. 3. Calculating a threshold value as percentage of maximum. 4. Automatic 3D lesion segmentation. 5. Quantitation of lesion volume and SUV. The procedure was developed using CTI CAPP and ECAT 7.2 software. Validation was done by phatom studies (Jaszczak phantom, various “lesion” sizes and contrasts) and on studies of NSCLC patients, who underwent clinical CT and FDG-PET scanning. Results: Phantom studies demonstrated a mean error of 3.5% for volume quantification using a threshold of 41% for contrast ratios ≥5 : 1 and sphere volumes >5 ml. Comparison between CT- and PET-based volumetry showed a high correlation of both methods (r = 0.98) for lesions with homogeneous FDG uptake. Radioactivity concentrations were underestimated by on average .41%. Employing an empirical threshold of 50% for SUV determination, the underestimation decreased to on average .34%. Conclusions: The algorithm facilitates an easy and reproducible SUV quantification and volume assessment of PET lesions in clinical practice. It was validated using NSCLC patient data and should also be applicable to other tumour entities.

TIRADS for sonographic assessment of hypofunctioning and indifferent thyroid nodules

AIM

To test the feasibility of the Thyroid Imaging Reporting And Data System (TIRADS) according to Horvath and Kwak for the assessment of thyroid nodules.

PATIENTS, METHOD

Retrospective analysis of patients with thyroid nodules applying the following inclusion criteria: B-mode-ultrasound, surgery and histological results. Thyroid nodules were classified as TIRADS 2, 3, 4A, 4B, 4C, 5 and 6.

RESULTS

A total of 172 patients were included (133 women, 48 ± 13 years, 39 men, 49 ± 11 years) with 222 thyroid nodules (24.9 ± 11.5 mm). Final histological diagnosis revealed 203 benign nodules (91%) and 19 malignant nodules (9%; 18 papillary thyroid carcinoma, PTC, and one medullary thyroid carcinoma, MTC). One hundred and sixty thyroid nodules were hypofunctioning in 99mTc-pertechnetate-scintigraphy, 14 nodules were hyperfunctioning and 46 nodules were classified as indifferent. In two cases with small carcinoma < 1 cm 99mTc-pertechnetate-scintigraphy was not performed. According to Horvath, the prevalence of malignancy was 6.7% in TIRADS 2, 0% in 3, 1.9% in 4A, 33% in 4B, 12.5% in 5 and 100% in 6; 73 nodules (39%) were not clearly classifiable, including 3 carcinoma (4.1%). According to Kwak, the prevalence of malignancy was 6.9% in TIRADS 2, 0% in 3, 2% in 4A, 4.1% in 4B, 23.1% in 4C, and 100% in 5 and 6, respectively. Notably, in the subgroup of hot nodules, 11 (79%) were graded as TIRADS 4A or higher, and thus advisable for fine-needle aspiration biopsy in both TIRADS.

CONCLUSION

The TIRADS described by Horvath is not practicable due to numerous unclassifiable nodules. The revised TIRADS published by Kwak is feasible and suitable to assess the prevalence of malignancy, but it cannot replace scintigraphic imaging. Fine-needle-biopsy is not necessary in nodules categorized as (K)TIRADS 3, 4A and 5.

[99mTc-MIBI scintigraphy of hypofunctional thyroid nodules. Comparison of planar and SPECT imaging]

99mTc-MIBI-scintigraphy allows to assess the dignity of hypofunctional thyroid nodules. A concordant pattern in MIBI- and pertechnetate-scintigraphy excludes malignancy with high accuracy. For increased MIBI-uptake histological evaluation is advised. The assessment of MIBI-isointense nodules is discussed controversially. Objective of our study was to analyse the prevalence of malignancy for isointense nodules and the diagnostic accuracy of image acquisition in SPECT-technique.

PATIENTS, METHODS

MIBI-scintigraphies were analysed retrospectively. Imaging was performed 60 min after intravenous injection of 510 MBq 99mTc-MIBI. Thyroid nodules were assessed as hypo-, iso- or hyperintense compared to the paranodular tissue.

RESULTS

83 of 225 patients underwent thyroid surgery (age 48.6 ± 12.6 years, 72% women). In 12 (14.5%) cases a papillary carcinoma was diagnosed. In planar imaging 12, 34 and 37, in tomographical imaging 16, 21 and 46 nodules, respectively, were classified as hypo-, iso- oder hyperintense. Among hypo-, iso- and hyperintense nodules in planar imaging 1, 5 and 6 carcinomas were found, resp. In tomographical imaging no, 4 and 8 carcinomas were found, respectively. Classification of iso- and hyperintense nodules as "suspicious for malignancy" showed for planar imaging a sensitivity, specificity, NPV and PPV of 91.7, 15.5, 91.7 and 15.6%, for tomographical imaging of 100, 22.5, 100 and 17.9%, respectively.

CONCLUSION

Hypofunctional thyroid nodules with iso- and hyperintense MIBI-Uptake have a comparable prevalence of malignancy. Image acquisition in SPECT-technique results in improved diagnostic sensitivity and negative predictive value.

Thyroiditis de Quervain. Are there predictive factors for long-term hormone-replacement?

BACKGROUND

Subacute thyroiditis is a usually self-limiting disease of the thyroid. However, approximately 0.5-15% of the patients require permanent thyroxine substitution. Aim was to determine predictive factors for the necessity of long-term hormone-replacement (LTH).

PATIENTS, METHODS

We retrospectively reviewed the records of 72 patients with subacute thyroiditis. Morphological and serological parameters as well as type of therapy were tested as predictive factors of consecutive hypothyroidism.

RESULTS

Mean age was 49 ± 11 years, f/m-ratio was 4.5 : 1. Thyroid pain and signs of hyperthyroidism were leading symptoms. Initial subclinical or overt hyperthyroidism was found in 20% and 37%, respectively. Within six months after onset 15% and 1.3% of the patients developed subclinical or overt hypothyroidism, respectively. At latest follow-up 26% were classified as liable to LTH. At onset the thyroid was enlarged in 64%, and at latest follow-up in 8.3%, with a significant reduction of the thyroid volume after three months. At the endpoint the thyroid volume was less in patients in the LTH group compared with the non-LTH group (41.7% vs. 57.2% of sex-adjusted upper norm, p = 0.041). Characteristic ultrasonographic features occurred in 74% of the patients in both lobes. Serological and morphological parameters as well as type of therapy were not related with the need of LTH.

CONCLUSIONS

In this study the proportion of patients who received LTH was 26%. At the endpoint these patients had a lower thyroid volume compared with euthyroid patients. No predictive factors for LTH were found.

Risk of malignancy in follicular thyroid neoplasm: predictive value of thyrotropin

The cytological diagnosis of follicular neoplasm is a common finding in fine needle aspiration cytology (FNAC) of thyroid nodules and includes benign disease as well as differentiated thyroid cancer. The aim of the study is to determine if thyrotropin is a predictive factor for a malignant nature of follicular neoplasm.

PATIENTS, METHODS

The records of 119 patients with follicular neoplasm on FNAC, who underwent surgery for final diagnosis, were reviewed retrospectively. The predictive value of serum parameters including thyrotropin, thyroglobulin, and anti-thyroid antibodies, ultrasonographic criteria and clinical variables was evaluated by univariate analysis and logistic regression analysis.

RESULTS, DISCUSSION

Patients with malignant nodules showed a higher thyrotropin concentration compared to patients with benign nodules (median 1.6 mU/l, interquartile range 1.4-3.0 mU/l vs. median 1.2 mU/l, interquartile range 0.8-1.6 mU/l, p < 0.01). ROC-analysis of thyrotropin revealed an optimal cut off value to differentiate benign and malignant nodules of 1.34 mU/l. The incidence of malignancy was 30.3% for a thyrotropin concentration higher than 1.34 mU/l compared to 6.4% for a thyrotropin concentration lower than or equal to 1.34 mU/l. On univariate analysis thyroglobulin higher than 300 ng/ml, positive anti-thyroid antibodies, hypoechogenicity, and ill-defined margins, respectively, were also significantly associated with malignancy. On logistic regression analysis higher thyrotropin concentrations, ill-defined margins, and thyroglobulin higher than 300 ng/ml, respectively, were independent predictive factors for malignancy (OR 20.0, 10.7, and 22.7, respectively).

CONCLUSION

Higher thyrotropin concentrations are predictive for a malignant nature of follicular neoplasm.

[Scintigraphically "hot" thyroid nodules mainly go hand in hand with a normal TSH]

AIM

In recent years, various professional societies published guidelines for diagnostic evaluation of thyroid nodules, in which the indication for scintigraphy is restricted to patients with subnormal TSH values. It is seen controversial whether such recommendations should be transferred to Germany, partly because of lower iodine intake in this country and the consequent higher percentage of autonomous thyroid nodules, which are not accompanied by a measurable dysfunction. Since reliable data to this topic are scarce, we analyzed multicentrically the spectrum of scintigraphically "hot" and "warm" nodules under the current epidemiological conditions.

PATIENTS, METHODS

In 10 German nuclear medicine out-patient institutions we evaluated the diagnostic data from a total of 514 patients, in whom unequivocally hyperfunctional nodules (focal increased uptake in comparison to perinodular tissue with a sonographically nodular correlative ≥1 cm) could be detected by (99m)Tc-pertechnetate scintigraphy. To minimize selection bias, the surveys were not carried out in hospitals.The recorded parameters included the thyroid hormone levels, the global (99m)Tc-uptake (TcTU), the size of each nodule and the total autonomous nodular volume (V(aut)).

RESULTS

Only 20% of the patients with "hot" nodules had subnormal TSH levels (<0.1 to 0.33 mU / l), the remaining patients had TSH levels from 0.34 to 3.5 mU /l (in one third of the patients TSH levels even exceeded 1.0 mU/l). Moreover, we found no relevant correlation between TSH and TcTU or V(aut).

CONCLUSIONS

In Germany, in at far the largest proportion of patients with autonomous thyroid nodules objectified by means of scintigraphy, TSH levels are within the normal range. Since such nodules with maximum safety can be classified as benign, a corresponding scintigraphic finding has a high priority for the patient. These current data support that it is not reasonable to restrict scintigraphy to patients with subnormal TSH values in this country.

[3D volume and SUV analysis of oncological PET studies: a voxel-based image processing tool with NSCLC as example]

AIM

The standardized uptake value (SUV) of 18FDG-PET is an important parameter for therapy monitoring and prognosis of malignant lesions. SUV determination requires delineating the respective volume of interest against surrounding tissue. The present study proposes an automatic image segmentation algorithm for lesion volume and FDG uptake quantitation.

METHODS

A region growing-based algorithm was developed, which goes through the following steps: 1. Definition of a starting point by the user. 2. Automatic determination of maximum uptake within the lesion. 3. Calculating a threshold value as percentage of maximum. 4. Automatic 3D lesion segmentation. 5. Quantitation of lesion volume and SUV. The procedure was developed using CTI CAPP and ECAT 7.2 software. Validation was done by phatom studies (Jaszczak phantom, various "lesion" sizes and contrasts) and on studies of NSCLC patients, who underwent clinical CT and FDG-PET scanning.

RESULTS

Phantom studies demonstrated a mean error of 3.5% for volume quantification using a threshold of 41% for contrast ratios >or=5 : 1 and sphere volumes >5 ml. Comparison between CT- and PET-based volumetry showed a high correlation of both methods (r = 0.98) for lesions with homogeneous FDG uptake. Radioactivity concentrations were underestimated by on average -41%. Employing an empirical threshold of 50% for SUV determination, the underestimation decreased to on average -34%.

CONCLUSIONS

The algorithm facilitates an easy and reproducible SUV quantification and volume assessment of PET lesions in clinical practice. It was validated using NSCLC patient data and should also be applicable to other tumour entities.

[Spectrometric assessment of thyroid depth within the radioiodine test]

Aim of this study is the validation of a simple method for evaluating the depth of the target volume within the radioiodine test by analyzing the emitted iodine-131 energy spectrum.

PATIENTS, METHODS

In a total of 250 patients (102 with a solitary autonomous nodule, 66 with multifocal autonomy, 29 with disseminated autonomy, 46 with Graves' disease, 6 for reducing goiter volume and 1 with only partly resectable papillary thyroid carcinoma), simultaneous uptake measurements in the Compton scatter (210 +/- 110 keV) and photopeak (364-45/+55 keV) windows were performed over one minute 24 hours after application of the 3 MBq test dose, with subsequent calculation of the respective count ratios. Measurements with a water-filled plastic neck phantom were carried out to perceive the relationship between these quotients and the average source depth and to get a calibration curve for calculating the depth of the target volume in the 250 patients for comparison with the sonographic reference data. Another calibration curve was obtained by evaluating the results of 125 randomly selected patient measurements to calculate the source depth in the other half of the group.

RESULTS

The phantom measurements revealed a highly significant correlation (r = 0,99) between the count ratios and the source depth. Using these calibration data, a good relationship (r = 0,81, average deviation 6 mm corresponding to 22%) between the spectrometric and the sonographic depths was obtained. When using the calibration curve resulting from the 125 patient measurements, the overage deviation in the other half of the group was only 3 mm (12%). There was no difference between the disease groups.

CONCLUSION

The described method allows on easy to use depth correction of the uptake measurements providing good results.

[Concept and validation of a simple model of the intrathyroidal iodine kinetics]

AIM of this study is the introduction and validation of a simple model of the intrathyroidal iodine kinetics, designed for optimizing radioiodine therapy planning and dose measurement in a routine clinical setting.

METHODS

The new model defines the intrathyroidal iodine kinetics as balance of the thyroidal iodine intake and -excretion, characterized by the two exponential equations A(t) = A(0) * (1-exp(-lambda(1) t)) and A(t) = A(0) * (exp(-lambda(2) t) -1), respectively. A(0) describes the theoretically maximum iodine uptake when the thyroidal iodine excretion is ignored, lambda(1) and lambda(2) represent the constants characterizing the iodine intake and excretion, respectively. The thyroidal iodine content at the time t equals the sum of both functions, which is A(t) = A(0) * (exp(-lambda(2) t)-exp(-lambda(1) t)). In 25 patients with autonomous goiter / nodules (n = 18), Graves' disease (n = 5), or endemic euthyroid goiter (n = 2), the iodine uptake in the thyroid during the radioiodine therapy as fraction of the applied activity was determined daily, with the remaining body covered by a lead shield. On average, 7.2 measurements were performed per patient (minimum 4, maximum 13). With these uptake values, individual regression curves were fitted using the above equation, and the difference between the actual measurements and the corresponding values of the regression curves was determined.

RESULTS

The average deviation of the 179 uptake values from the calculated points of the respective regression curves was only 1.4%. There was no significant difference between the three disease groups. The distribution of the relative deviations during the individual courses was constant, systematic errors were not detected.

CONCLUSION

Our results suggest that the intrathyroidal iodine kinetics can be precisely described with the model A(t) = A(0) * (exp(-lambda(2) t)-exp(-lambda(1) t)). With only three measurements, the trend of the curve can be calculated, which allows to determine the total radioiodine storage in the thyroid.

Radioiodine therapy in patients with hyperthyroid disorder: standard versus dosimetric activity application

Due to its high success rate and non-invasive character, an increasing demand for radioiodine therapy can be seen. This study was conducted to determine whether standardized 131I activities can be used to facilitate management of patients with hyperthyroid disorder or whether a pre-therapeutic radioiodine test is advisable to determine an adequate therapeutic activity. The therapeutic uptake of 218 patients with benign thyroid disorders were determined and compared with 24 h and 48 h test uptake measurements as well as with calculated standard uptake values. Since there is a linear relationship between iodine uptake and delivered radiation dose, the effect of the different therapeutic approaches on the latter parameter was analysed. Special care was taken to assess possible differences between the various thyroid disorders. A mean deviation between pre-therapeutic test uptake and actual therapeutic uptake of 14.7% was observed in contrast to one of 29.1% when using disease specific standard values per millilitre of thyroid tissue. Furthermore, the proportion of patients with large deviations of more than 40% increased drastically when using standard uptake values (with radioiodine test, 4.1%; with standard values, 18.8%). In conclusion, the dosimetric approach with a pre-therapeutic radioiodine test proved to be the most accurate therapeutic procedure. Both the 24 h and 48 h test uptake measurements gave analogous results and yielded a correlation coefficient of 0.91 when compared with the therapeutic uptake. While it may be tempting to use standard activities to facilitate patient management, the findings of this study confirm that, for precise therapy planning, a pre-therapeutic radioiodine test is advised. Since no significant difference could be found between the 24 h and 48 h test uptake values, an early measurement 24 h after administration of the test activity is recommended.

[Relevance of colour-duplex echography for detection and therapy of recurrences in the follow-up of head and neck cancer]

BACKGROUND

Head and neck malignancies have a high rate of recurrences. Since the prognosis is often limited an early detection and therapy onset is essential for survival. This study surveys the relevance of regular colour-duplex echography examinations in the follow-up for detection and therapy of recurrent head and neck carcinomas.

PATIENTS AND METHODS

In a prospective non-randomized study 43 patients were surveyed over a mean observation period of 28 (8-44) months. In addition to clinical and colour-duplex echography (CDS) examinations, computed tomography (CT) and positron-emission-tomography using 18fluorodeoxyglucose (PET) were performed.

RESULTS

A recurrence was detected in 17/43 (39.5 %) patients. The median survival was 42 months. CDS was the most reliable procedure for the diagnosis of regional recurrences with an accuracy of 94.2 %. Sensitivity and specificity of CDS for the diagnosis of all recurrences was found to be 80 % and 78,6 % respectively. CT yielded identical results. In PET sensitivity was 82.4 % and specificity was found to be 88.4 %. In clinical examinations including panendoscopy sensitivity was 64.7 % only. In 7/17 recurrences a therapy was performed with curative intention. In 4 cases an early diagnosis by CDS contributed to a successful therapy.

CONCLUSION

CDS is the imaging procedure of choice for the routine follow-up of head and neck cancer patients. In order to perform a comprehensive assessment of the head and neck region, for re-staging and to exclude second primary tumours additional (pan)endoscopy is necessary. CDS supports due to a high resolution and reliability an early therapy onset and a minimal invasive therapy. Thus, this procedure can significantly contribute to the successful treatment of recurrences in head and neck cancer.

Pre-transplant positron emission tomography (PET) using fluorine-18-fluoro-deoxyglucose (FDG) predicts outcome in patients treated with high-dose chemotherapy and autologous stem cell transplantation for non-Hodgkin's lymphoma

We investigated the predictive value of sequential FDG PET before and after high-dose chemotherapy (HDT) and autologous stem cell transplantation (ASCT) in 24 patients suffering from non-Hodgkin's lymphoma (NHL). FDG PET was performed at baseline, after three cycles of induction therapy, before and after HDT with ASCT. Response assessment from sequential PET scans using standardized uptake values (SUV) was available in 22 patients at the time of transplantation. Partial metabolic response (PMR) was defined as a >25% decrease of SUV between successive PET scans [corrected]. Six of seven patients who did not achieve a PMR after complete induction therapy developed lymphoma progression, while 10 of 15 patients with complete metabolic response (CMR) or PMR remained in continuous remission. Four of seven patients with less than PMR after induction therapy died vs two of 15 patients with CMR/PMR. Median progression-free and overall survival of patients with less than PMR after HDT and ASCT was 9 and 29 months, respectively. In contrast, neither conventional re-staging nor the International Prognostic Index were predictive. These data suggest that sequential quantitative PET imaging does enlarge the concept of chemosensitivity used to select patients with high-risk NHL for HDT and ASCT or to route them to alternative treatments.

Uptake of cis-4-[18 F]fluoro-L-proline in scar formation: a marker of collagen synthesis?

Excessive scar formation is accompanied by abnormal collagen synthesis. The feasibility of monitoring collagen synthesis in vivo with no-carrier-added cis-4[18F]fluoro-L-proline (cis-FPro) was evaluated in an animal model with scar formation induced by implanted meshes. The abdominal wall of rats was replaced by alloplastic meshes. At days 3, 7, 14, 21 and 90 after implantation, the uptake of cis-FPro at 4 h post-injection was determined for resected samples of the mesh and normal tissues. The highest uptake was found in the kidneys (1.73+/-0.47%ID/g) followed by the liver (0.59+/-0.19%ID/g). The meshes showed the maximum uptake at day 3 (0.20+/-0.07%ID/g) with a decrease to 0.10+/-0.03%ID/g at day 90 (P<0.001). After 3 days no connective tissue was shown by histopathological morphometric analysis. The maximum partial volume (PV%) of connective tissue was 43+/-14 PV% 90 days after implantation. The maximum levels of granulocytes and inflammatory infiltrate were found at day 3 with minimal levels at day 90, paralleling the course of cis-FPro uptake. In conclusion, the uptake of cis-FPro at 4 h post-injection is not related to the content of connective tissue. Cis-FPro radiolabelled with 18F appears not to be a suitable radiopharmaceutical for in vivo monitoring of collagen synthesis in scar formation.

Combined image interpretation of computed tomography and hybrid PET in head and neck cancer

AIM

Evaluation of potential synergistic effects of combined image interpretation of FDG PET using a gamma camera modified for coincidence detection (hybrid PET) and computed tomography (CT) and comparison of the diagnostic accuracy of hybrid PET and dedicated PET in patients with head and neck cancer.

METHODS

Forty-two patients with suspected primary or recurrent cancer were included. Twenty-four patients underwent dedicated PET in addition to attenuation-corrected hybrid PET using a one-day protocol.

RESULTS

Sensitivity, specificity and accuracy for detection of primary or recurrent head and neck cancer were 74, 73, and 74% for hybrid PET, 52, 82, and 60% for CT and 77, 82, and 79% for combined reading. With the combination of CT and hybrid PET all cases of recurrent disease were detected. The largest tumour not detected was 1.7 cm in diameter. Sensitivity, specificity and accuracy for the detection of neck sides with lymph node metastases were 69, 88, and 85% for hybrid PET, 62, 88, and 84% for CT, 69, 99, and 94% for combined image interpretation. With combined interpretation four involved neck sides were missed including two cases of microscopic metastases. Hybrid PET revealed concordant results to dedicated PET in all patients with respect to the detection of primary or recurrent tumour and in 45 of 48 neck sides (94%) with the same number of false negative findings.

CONCLUSION

The combination of functional information of hybrid PET and morphological information of CT by the simple approach of combined image interpretation improves the sensitivity for the detection of primary/recurrent head and neck cancer and increases the specificity of lymph node staging compared to CT alone. The accuracy of hybrid PET and dedicated PET was almost identical.

2-[Fluorine-18]-fluoro-2-deoxy-d-glucose positron emission tomography in the diagnosis of recurrent ovarian cancer

OBJECTIVE

The aim of the study was to investigate the role of 2-[fluorine-18]-fluoro-2-deoxy-d-glucose positron emission tomography (FDG PET) in the diagnosis of recurrent ovarian cancer.

METHODS

One hundred six FDG PET scans performed in 54 patients in the follow-up after cytoreductive surgery and chemotherapy of ovarian cancer were reevaluated. Fifty-eight scans were performed in patients with suspected recurrence and 48 scans in patients who were clinically disease free. Thirty-seven PET scans were validated by histology and 66 studies by a median follow-up of 22 months in disease-free patients or 12 months in patients with recurrent disease. Three scans were validated by concordant positive findings of tumor marker CA125, computed tomography, and FDG PET.

RESULTS

FDG PET correctly identified recurrent disease in 73/88 cases. PET ruled out recurrent disease in 15/18 cases. The sensitivity and specificity for PET were 83 and 83%, respectively. In patients with suspected disease, sensitivity was 94% compared to 65% in patients judged clinically disease free. The sensitivity of PET was 96% if suspicion of recurrence was based on a rise of CA125 alone. PET preceded the conventional diagnosis by a median of 6 months in patients judged clinically free of disease. The median relapse-free interval after a negative PET scan was 20 months.

CONCLUSION

FDG PET provides the chance to detect recurrent ovarian cancer at an earlier stage during follow-up. Patients with a negative PET scan have a longer relapse-free interval than patients with a positive PET scan.

Localisation of motor areas in brain tumour patients: a comparison of preoperative [18F]FDG-PET and intraoperative cortical electrostimulation

Assessment of the exact spatial relation between tumour and adjacent functionally relevant brain areas is a primary tool in the presurgical planning in brain tumour patients. The purpose of this study was to compare a preoperative fluorine-18 fluorodeoxyglucose positron emission tomography ([18F]FDG PET) activation protocol in patients with tumours near the central area with the results of intraoperative direct cortical electrostimulation, and to determine whether non-invasive preoperative PET imaging can provide results equivalent to those achieved with the invasive neurosurgical "gold standard". In this prospective study, we examined 20 patients with various tumours of the central area, performing two PET scans (each 30 min after i.v. injection of 134-341 MBq [18F]FDG) in each patient: (1) a resting baseline scan and (2) an activation scan using a standardised motor task (finger tapping, foot stretching). Following PET/MRI realignment and normalisation to the whole brain counts, parametric images of the activation versus the rest study were calculated and pixels above categorical threshold values were projected to the individual MRI for bimodal assessment of morphology and function (PET/MRI overlay). Intraoperative direct cortical electrostimulation was performed using a Viking IV probe (5 pulses, each of 100 micros) and documented using a dedicated neuro navigation system. Results were compared with the preoperative PET findings. PET revealed significant activation of the contralateral primary motor cortex in 95% (19/20) of the brain tumour patients (hand activation 13/13, foot activation 6/7), showing a mean increase in normalised [18F]FDG uptake of 20.5% +/- 5.2% (hand activation task) and 17.2% +/- 2.5% (foot activation task). Additionally detected activation of the ipsilateral primary motor cortex was interpreted as a metabolic indication for interhemispheric compensational processes. Evaluation of the PET findings by cortical stimulation yielded a 94% sensitivity and a 95% specificity for identification of motor-associated brain areas. In conclusion, the findings indicate that a relatively simple and clinically available [18F]FDG PET activation protocol enables a sufficiently precise assessment of the local relation between the intracranial tumour and the adjacent motor cortex areas and may facilitate the presurgical planning of tumour resection.

[Fluorodeoxyglucose positron emission tomography (FDG-PET) in the differential diagnosis of pancreatic lesions]

Various diagnostic modalities have been introduced for the diagnostic work-up of suspected pancreatic cancer. However, the differentiation of pancreatic cancer and chronic pancreatitis is still a challenge. Positron emission tomography (PET) with radiolabeled fluorodeoxyglucose (FDG) is an imaging modality that is based on the increased glucose metabolism of malignant cells. In contrast to conventional imaging, which provides morphological information, FDG-PET demonstrates functional alterations of malignant tumours. The value of FDG-PET in differentiating pancreatic lesions has been validated by numerous studies with variable patient selection criteria. In these studies a sensitivity between 71% and 100% and a specificity between 64% and 100% was reported. The median sensitivity was 92% and the median specificity 82%. The diagnostic accuracy was limited in hyperglycemic patients and in patients with active inflammation of the pancreas, as is found in acute pancreatitis or active chronic pancreatitis. These limitations have to be taken into account for the indication of FDG-PET as well as the interpretation of PET findings.

Analysis of FDG uptake with hybrid PET using standardised uptake values

The standardised uptake value (SUV) has been used as an index of glucose metabolism to classify malignant tumours. To date, calculation of SUVs has been restricted to dedicated PET. The aim of this study was to investigate the feasibility of SUV calculation with attenuation-corrected hybrid PET, applying a singles count rate-related calibration method. Calibration factors for hybrid PET at different singles count rates were determined by phantom studies. SUVs were determined for hot spheres in a phantom study as well as for 68 malignant lesions in 56 patients. Recovery coefficients calculated for hot spheres were applied to SUVs of malignant lesions to correct for partial volume and recovery effects. At a sphere-to-background ratio of 10:1, SUVs of spheres with diameters from 34 to 16 mm varied from 5.0 to 1.5 for hybrid PET, and from 8.0 to 4.3 for dedicated PET. SUVs of malignant lesions calculated by hybrid and dedicated PET showed a strong correlation (r=0.95, P<0.001), with a mean percentage difference of 36%. SUVs calculated by hybrid PET were significantly lower than SUVs calculated by dedicated PET (6.2+/-4.3 vs 8.5+/-5.3, P<0.001). Application of recovery coefficients revealed an SUV of 12.2+/-7.3 for hybrid PET versus 10.8+/-6.3 for dedicated PET, with a significant reduction in the mean percentage difference (22%, P<0.01). In conclusion, singles count rate-related calibration factors allow calculation of SUVs with hybrid PET for lesions with a diameter larger than 15 mm. Correction for partial volume and recovery effects is needed to improve the agreement of SUVs of lesions determined by hybrid PET and dedicated PET.

Optimizing ventilation-perfusion lung scintigraphy: parting with planar imaging

AIM

Of the study was to introduce and verify a ventilation-perfusion (V/Q) acquisition protocol that incorporates new developments in scintigraphy in order to allow for a more balanced comparison with other diagnostic procedures.

METHODS

In 103 patients suspect of having pulmonary embolism, V/Q scans were acquired exclusively with SPECT technique. Ventilation was done with ultrafine aerosol. Planar images in eight directions were reconstructed through addition of three consecutive SPECT projections. Three referees examined the scans in regard to type, localization, and extent of V/Q defects.

RESULTS

Using this protocol, significantly more defects, especially of subsegmental size, were detected (p < 0.01). Sensitivity, and diagnostic accuracy were also significantly improved (p < 0.01) to 0.96, and 0.99, respectively. Furthermore, kappa values were increased up to 0.82--a relevant enhancement in the ability to precisely localize V/Q defects.

CONCLUSION

In conclusion this protocol provides high-resolution tomographic scans as well as high-quality planar images within a short acquisition time. Due to the significant increase in lesion detection, sensitivity, diagnostic accuracy, and anatomical localization of defects, it is a substantial improvement in the diagnosis of pulmonary embolism that will put V/Q scintigraphy on a par with other tomographic methods.

Prognostic significance of positron emission tomography using fluorine-18-fluorodeoxyglucose in patients treated for malignant lymphoma

AIM

To evaluate the prognostic significance of positron emission tomography (PET) using fluorine-18-[2]-fluoro-2-deoxyglucose (FDG) in patients treated for Hodgkin's disease (HD) or non-Hodgkin's lymphoma (NHL) compared to conventional restaging (CRS).

METHODS

Fifty-six patients with either HD (n = 22), high-grade NHL (n = 26) or centrocytic-centroblastic NHL (n = 8) were included. PET was performed in 41 patients for treatment reevaluation up to three months after therapy and in patients with persisting residual masses (n = 10) or suspected relapse (n = 5) four to twelve months after treatment. The scans were evaluated qualitatively and quantitatively using standardised uptake values (SUV). Progression-free survival (PFS) was estimated to assess the prognostic value of FDG PET and clinical follow-up was taken as gold standard.

RESULTS

PET was positive in nineteen of 41 patients studied for treatment reevaluation. Progression was observed after a median interval of two months (range 0-15) in sixteen of 19 patients after a positive PET scan and in three of 22 patients after a negative scan (p < .001). Median duration of follow-up in progression-free patients was 21 months (range 6-72). In patients with a partial remission in CRS progression was more common in PET-positive than in PET-negative patients (5 of 7 vs. 1 of 14; p < .01) and positivity with PET was associated with poorer PFS (p < .0025). PET studies performed four to twelve months after treatment were true negative in seven, true positive in five and false-positive in three patients. SUV > 11.35 of lymphoma lesions was associated with poorer PFS than SUV < 11.35 (p < 0.025).

CONCLUSION

We conclude that FDG PET after treatment of malignant lymphoma has a high prognostic value and should be recommended in patients with persistence of residual masses.

[Characterization of therapy failures in radioiodine therapy of Graves' disease without simultaneous antithyroid agents]

Aim of this study was a characterization of radioiodine therapy (RIT) failures in Graves' disease without simultaneous carbimazole.

METHOD

226 patients with a confirmed diagnosis of Graves' disease received 686.8 +/- 376.4 MBq of iodine-131 orally for thyroid ablation. Target dose was 250 Gy. All patients were followed up for 6 months. Therapy failures were compared with successes regarding possible influencing variables initial thyroid volume, thyroid function, immune activity (TRAb), I-131 uptake, effective half-life, absorbed energy dose, age and gender.

RESULTS

212 of 226 patients (93.8%) were treated successfully, 14 (6.2%) showed a hyperthyroidism relapse within 6 months which required a second radioiodine therapy. A success rate of 92.5% (62/67) could also be achieved with 67 patients who were hyperthyroid at the time of RIT. Compared to the therapy successes, the 14 failures achieved significantly lower absorbed doses (223.8 +/- 76.6 Gy vs. 285.2 +/- 82.1 Gy, p < 0.005), but with no significant differences regarding age, thyroid volume, function or TRAb (all p > 0.2). Of the 14 failures, n = 8 reached an absorbed dose < 200 Gy and n = 1 a dose < 250 Gy, although 5 of the failures reached an absorbed dose of > 250 Gy. Stepwise logistic regression revealed only absorbed energy dose as a variable significantly influencing therapy success (p < 0.005), but no influence of initial thyroid volume, function, TRAb value, age (all p > 0.2) or gender (p = 0.13). Two-tailed Fisher's exact test showed no significant influence of gender on success rates (failures/successes: male 1/36, female 13/176, p = 0.48).

CONCLUSIONS

Except for the absorbed energy dose, no other significant variable influencing the outcome of radioiodine therapy in Graves' disease without simultaneous carbimazole could be found. It should be noted, though, that 5 therapy failures (2.2%) reached an absorbed energy dose of > 250 Gy.

[Low-grade malignant peripheral nerve sheath tumor of the neck soft tissues]

BACKGROUND

Malignant Peripheral Nerve Sheath Tumours (MPNST) either grow sporadically, after radiation or chemotherapy respectively. In many cases they are associated with Neurofibromatosis I. Because of the multiform histologic picture they are often difficult to differentiate from other soft tissue tumours.

PATIENT

We present the case of a sporadic MPNST which developed from the vagus nerve of a 39-year-old patient following radiation of the neck 7 years before. After complete excision there has been no recurrence up to now.

RESULTS AND CONCLUSIONS

Sporadic MPNST of the head and neck are comparatively rare. With regard to the strong association with Neurofibromatosis I and the difficult differential diagnosis to other soft tissue tumours the emphasis should be put on excluding further manifestations of Neurofibromatosis I and of secondary tumours.

Does thyroid stunning exist? A model with benign thyroid disease

With regard to the treatment of differentiated non-medullary thyroid carcinoma, there is controversy over whether radiation from a diagnostic radioiodine (131I) application really does have a suppressive effect on the uptake of subsequent therapeutic 131I (so-called thyroid stunning). However, inherent difficulties in exact remnant/metastatic tissue volumetry make it difficult to quantify how much diagnostic 131I is actually absorbed (absorbed energy dose) and hence to decide whether a threshold absorbed dose exists beyond which such stunning would occur. Since in benign thyroid disease the target volume can be readily quantified by ultrasonography, we sought to determine definitely whether stunning of thyroid cells occurs upon a second application of radioiodine 4 days following the first one. We therefore studied 171 consecutive patients with benign thyroid disease (diffuse goitre, Graves' disease, toxic nodular goitre) who received two-step 131I therapy during a single in-patient stay. For application of both calculated 131I activities we performed kinetic dosimetry of 131I uptake, effective half-life and absorbed dose. At the second application, patients showed significant stunning (a 31.7% decrease in 131I uptake, from 34.7% +/- 15.4% at first application to 23.7% +/- 12.3% at second application, P < 0.0005) without a significant difference in effective half-life (4.9 +/- 1.3 vs 5.0 +/- 1.7 days, P > 0.2). ANOVA showed that the extent of stunning was influenced significantly only by the absorbed energy dose at first application (F = 13.5, P < 0.0005), while first-application 131I activity, target volume, gender and thyroid function had no influence (all F < or = 0.71, all P > 0.4). There was no significant correlation between extent of thyroid stunning and first-application 131I activity ( r = 0.07, P > 0.3), whereas there was a highly significant correlation between thyroid stunning and first absorbed energy dose (r = 0.64, P < 0.00005), the latter correlation fitting a logarithmic model best. Multivariate factor analysis also revealed first absorbed energy dose to be the only decisive stunning factor. In conclusion, our study confirms that stunning exists in benign thyroid conditions and that it is a purely radiobiological inhibitory phenomenon related to absorbed dose.

Is prostate-specific antigen a reliable marker of bone metastasis in patients with newly diagnosed cancer of the prostate?

OBJECTIVE

Staging in patients with newly diagnosed cancer of the prostate has significant ramifications in the management of the disease. At present, measurement of serum prostate-specific antigen (PSA) concentration and radionuclide bone scintigraphy are two important procedures in the metastatic work-up of these patients. We evaluated the efficacy of PSA as a staging marker to discriminate prostate cancer patients with and without bone metastases.

METHODS

In a retrospective study, 359 prostate cancer patients with (n = 40) and without (n = 319) bone metastases were analyzed. In all patients the initial PSA measurement as well as the radionuclide bone scan were evaluated.

RESULTS

Patients without bone metastases demonstrated a median serum PSA concentration of 12 ng/ml, whereas those with bone metastases revealed a median serum PSA concentration of 59 ng/ml, with 7 patients demonstrating a serum PSA concentration of < 10 ng/ml. This resulted in a negative predictive value of 96%. In addition, only 40% of these patients with bone metastases demonstrated a serum PSA concentration of > 100 ng/ml, which resulted in a positive predictive value of 50%.

CONCLUSION

The serum PSA concentration seems only to provide limited information with regard to the presence of bone metastasis in patients with newly diagnosed cancer of the prostate. We therefore question whether a staging radionuclide bone scan may be omitted in patients with a serum PSA value of < 10 ng/ml.

Diagnosis of myocardial viability by dual-head coincidence gamma camera fluorine-18 fluorodeoxyglucose positron emission tomography with and without non-uniform attenuation correction

This study assessed a dual-head coincidence gamma camera (hybrid PET) equipped with single-photon transmission for myocardial fluorine-18 fluorodeoxyglucose (FDG) imaging by comparing this technique with conventional positron emission tomography (PET) using a dedicated ring PET scanner. Twenty-one patients were studied with dedicated FDG ring PET and FDG hybrid PET for evaluation of myocardial glucose metabolism, as well as technetium-99m tetrofosmin single-photon emission tomography (SPET) to estimate myocardial perfusion. All patients underwent transmitted attenuation correction using germanium-68 rod sources for ring PET and caesium-137 point sources for hybrid PET. Ring PET and hybrid PET emission scans were started 61+/-12 and 98+/-15 min, respectively, after administration of 154+/-31 MBq FDG. Attenuation-corrected images were reconstructed iteratively for ring PET and hybrid PET (ac-hybrid PET), and non-attenuation-corrected images for hybrid PET (non-ac-hybrid PET) only. Tracer distribution was analysed semiquantitatively using a volumetric vector sampling method dividing the left ventricular wall into 13 segments. FDG distribution in non-ac-hybrid PET and ring PET correlated with r=0.36 (P<0.0001), and in ac-hybrid PET and ring PET with r=0.79 (P<0.0001). Non-ac-hybrid PET significantly overestimated FDG uptake in the apical and supra-apical segments, and underestimated FDG uptake in the remaining segments, with the exception of one lateral segment. Ac-hybrid PET significantly overestimated FDG uptake in the apical segment, and underestimated FDG uptake in only three posteroseptal segments. A three-grade score was used to classify diagnosis of viability by FDG PET in 136 segments with reduced perfusion as assessed by SPET. Compared with ring PET, non-ac-hybrid PET showed concordant diagnoses in 80 segments (59%) and ac-hybrid PET in 101 segments (74%) (P<0.001). Agreement between ring PET and non-ac-hybrid PET was best in the basal lateral wall and in the apical-septal segment (80%-100%), and lowest in the apical, supra-apical and posteroseptal segments (41%-55%). Ac-hybrid PET showed highest agreement in the lateral wall (89%-100%), and lowest agreement in the apical and the basal septal segments (59%-67%). In conclusion, non-uniform attenuation correction with singles transmission significantly improves the diagnostic accuracy of myocardial dual-head gamma camera coincidence imaging with FDG. However, results equivalent to those obtained with ring PET cannot yet be attained, even if attenuation correction is applied. New rebinning algorithms for three-dimensional data may further improve the performance of ac-hybrid PET and should be evaluated in future studies.

Fluorodeoxyglucose positron emission tomography and the prognosis of pancreatic carcinoma

BACKGROUND

Pancreatic carcinoma is associated with a poor prognosis. The aim of this study was to determine whether glucose metabolism in pancreatic cancer has prognostic significance for patients suffering from this disease.

METHODS

The survival data of 52 patients with pancreatic carcinoma was correlated with the standardized uptake value (SUV) as a semiquantitative parameter of glucose metabolism, as determined with fluorodeoxyglucose positron emission tomography (FDG PET). A multivariate analysis, including SUV and accepted factors of prognosis, such as stage at presentation and tumor marker Ca 19-9, was performed to determine the prognostic value of FDG PET.

RESULTS

The median survival in 26 patients with low SUV (< 6.1) was 9 months (95% confidence interval 6-12 months) vs. 5 months (95% confidence interval 4-6 months) in 26 patients with high SUV (> or = 6.1). Multivariate analysis revealed SUV and tumor marker Ca 19-9 as independent factors of prognosis in patients with pancreatic carcinoma.

CONCLUSION

Glucose metabolism, as determined with FDG PET, provides additional prognostic information in patients with pancreatic carcinoma.

Benign versus malignant osseous lesions in the lumbar vertebrae: differentiation by means of bone SPET

Bone scanning is a well-accepted and frequently performed diagnostic procedure with a high sensitivity, especially when single-photon emission tomography (SPET) acquisitions are added. However, the differentiation of benign from malignant osseous lesions often poses difficulty. The purpose of this study was to find out whether the particular localisation of an intraosseous lesion in a lumbar vertebra is an indicator of its aetiology. Bone scintigraphy including planar whole-body scans as well as SPET imaging of the lumbar spine was performed in 109 patients. The diagnoses of osseous lesions in the lumbar vertebrae were made strictly on the basis of the findings of magnetic resonance imaging, computed tomography or plain radiography. Sixteen patients had to be excluded from the study because they did not undergo adequate radiological examination. To determine the particular localisation of vertebral lesions in the bone scan, two experienced nuclear medicine physicians examined the studies independently while blinded to the radiological results. Four anatomical regions were differentiated within the vertebra: the vertebral body, the pedicle, the facet joints and the spinous process. Clopper-Pearson analysis, which takes into account the number of examinations, yielded the following probability intervals for the malignancy of intraosseous lesions in the lumbar spine: vertebral body 36.8%-57.3%, pedicle 87.7%-100%, facet joints 0.8%-21.4% and spinous process 18.7%-81.3%. It was concluded that lesions affecting the pedicle are a strong indicator for malignancy, whereas involvement of the facet joints is usually related to benign disease. Lesions affecting the vertebral body or the spinous process do not show a clear tendency towards either malignancy or benignity. In contrast to other studies, a significant probability of malignancy (35.6%) was observed in lesions affecting exclusively the vertebral body.