The role of hybrid FDG-PET/MRI on decision-making in presurgical evaluation of drug-resistant epilepsy.

BACKGROUND: When MRI fails to detect a potentially epileptogenic lesion, the chance of a favorable outcome after epilepsy surgery becomes significantly lower (from 60 to 90% to 20-65%). Hybrid FDG-PET/MRI may provide additional information for identifying the epileptogenic zone. We aimed to investigate the possible effect of the introduction of hybrid FDG-PET/MRI into the algorithm of the decision-making in both lesional and non-lesional drug-resistant epileptic patients. METHODS: In a prospective study of patients suffering from drug-resistant focal epilepsy, 30 nonlesional and 30 lesional cases with discordant presurgical results were evaluated using hybrid FDG-PET/MRI. RESULTS: The hybrid imaging revealed morphological lesion in 18 patients and glucose hypometabolism in 29 patients within the nonlesional group. In the MRI positive group, 4 patients were found to be nonlesional, and in 9 patients at least one more epileptogenic lesion was discovered, while in another 17 cases the original lesion was confirmed by means of hybrid FDG-PET/MRI. As to the therapeutic decision-making, these results helped to indicate resective surgery instead of intracranial EEG (iEEG) monitoring in 2 cases, to avoid any further invasive diagnostic procedures in 7 patients, and to refer 21 patients for iEEG in the nonlesional group. Hybrid FDG-PET/MRI has also significantly changed the original therapeutic plans in the lesional group. Prior to the hybrid imaging, a resective surgery was considered in 3 patients, and iEEG was planned in 27 patients. However, 3 patients became eligible for resective surgery, 6 patients proved to be inoperable instead of iEEG, and 18 cases remained candidates for iEEG due to the hybrid FDG-PET/MRI. Two patients remained candidates for resective surgery and one patient became not eligible for any further invasive intervention. CONCLUSIONS: The results of hybrid FDG-PET/MRI significantly altered the original plans in 19 of 60 cases. The introduction of hybrid FDG-PET/MRI into the presurgical evaluation process had a potential modifying effect on clinical decision-making. TRIAL REGISTRATION: Trial registry: Scientific Research Ethics Committee of the Medical Research Council of Hungary. TRIAL REGISTRATION NUMBER: 008899/2016/OTIG . Date of registration: 08 February 2016.

[PET/CT based radiotherapy treatment planning in head and neck cancers]. / PET/CT alapú besugárzástervezéssel szerzett tapasztalatok fej-nyaki tumorokban.

The purpose of this study was to evaluate the experiences of PET/CT based radiation planning in patients suffering from head and neck cancer. PET/CT based 3D-conformal irradiation was used in eleven patients between March 2008 and February 2009. In six of the eleven cases the therapeutic plan was modified after PET/CT examination, as the previously determined lymph node negative state proved to be lymph node positive. For that reason, the treatment needed to be completed by chemotherapy and in some cases clinical target volume and planning target volume have been also modified. PET/CT examination has a decisive influence on therapeutic planning and on the planning process in patients with head and neck cancer.

[The advantage of Positron Emission Tomography combined with Computer Tomography (PET-CT) in the diagnosis of lung cancer (experience with 408 patients)]. / A számítógépes rétegvizsgálattal kombinált pozitronemissziós tomogrAFIA (PET-CT) diagnosztikus értéke tüdôrákban (Tapasztalataink 408 beteg kapcsán).

The authors analyzed the results of PET-CT scans made with oncological indications among 408 patients. One hundred and fifty-four PET-CTs were done to characterize pulmonary foci, after which in 59 cases lung surgery was performed. The method's sensitivity in respect to malignancy was 100%, specificity was 56%. Staging of affected lymph nodes resulted in 17 mediastinoscopies and 54 thoracotomies. In the former indications PET-CT-positive lymph nodes always need cytologic/histologic verification. M-staging done with PET-CT was performed in 141 cases, mediastinal restaging of patients having received neoadjuvant chemotherapy was done in 24 cases. The latter indications we consider superfluous because of the diagnostic inaccuracy of PET-CT. In 175 cases we analyzed the frequently determining factor of the PET-CT scan in the indication of lung surgery. The authors wish to share their experience for the better use of this method and to accelerate the inclusion of PET-CT into the diagnostic protocol.

Partial breast irradiation with interstitial 60CO brachytherapy results in frequent grade 3 or 4 toxicity. Evidence based on a 12-year follow-up of 70 patients.

PURPOSE: To investigate the radiation-induced toxicity and cosmesis of brachytherapy (BT) alone in early stage breast cancer. METHODS AND MATERIALS: A total of 70 women diagnosed with Stage I or II breast carcinoma participated in a BT study at the Municipal Oncoradiological Center, Uzsoki Hospital, Budapest, Hungary, between November 1987 and June 1992. They had undergone breast-conserving surgery with an unknown surgical margin. The postoperative tumor bed irradiation was performed with interstitial (60)Co sources with an active length of 4 cm, with 10-mm center-to-center spacing arranged in a single plane. The median number of inserted sources was 5 (range, 2-8), with a linear activity of 133-137 MBq/cm at the beginning of the study. The 50 Gy delivered dose at 5 mm from the surface of the (60)Co sources was administered during 10-22 h to the virtual postoperative lumpectomy cavity (i.e., plane). For radiobiologic considerations, the clinical target volume (CTV) was calculated retrospectively with a 10-mm safety margin, resulting in a 72-cm(3) median CTV (range, 36-108 cm(3)) irradiated with a reference dose of 28 Gy. In the assessment of the skin and subcutaneous toxicity, the RTOG late radiation morbidity scoring system was applied. The radiosensitivity of the cultured fibroblasts was determined by clonogenic assay to check whether individual radiosensitivity played a role in the development and course of radiation-induced side-effects. RESULTS: The median follow-up was 12 years (range, 10-15 years). The population of the final study (34 cases) comprised all survivors with tumor-free breasts (27 cases) and patients with breasts erroneously ablated/excised for misinterpreted radiation-induced sequelae (7 patients). A total of 97% of the cohort (33/34) had grade > or =2, and 59% (20/34) had grade > or =3 radiation-induced toxicity. By the end of the follow-up, 85% of the patients experienced Grade > or =2 telangiectasis and 41% had Grade 3 telangiectasis. Eighty-eight percent had fibrosis of some form, and 35% had grade > or =3 fibrosis. Forty-one percent of the cohort displayed fat necrosis, which was always accompanied by Grade > or =3 fibrosis or telangiectasis. The cosmetic results were poor in 50% (17/34) of the patients. The radiosensitivity of the fibroblasts was increased in only 2/24 patients (8% of the investigated cases, in agreement with data published for the general population). Comparisons of our fibrosis prevalence data with those of others allowed an estimate of 0.47 h(-1) for the rate of recovery of DNA damage in the fibroblasts. CONCLUSIONS: Interstitial (60)Co BT of the breast tumor bed alone with a limited CTV (median, 72 cm(3)) and a total dose of 28 Gy is associated with a high rate (59%) of grade > or =3 radiation-induced toxicity and a high rate (50%) of poor cosmetic outcome at the end of a median follow-up of 12 years. A relatively high BT dose rate (1.3-2.8 Gy/h) applied during a short overall treatment time (10-22 h) and a possible geographic miss (close to skin implantation) might have contributed to the development of these sequelae.

[Cost-effective PET investigations in oncology]. / Költség-hatékony onkológiai PET-vizsgálatok.

The authors have reviewed the financial considerations of oncological FDG PET examinations by the guidelines of the Health Care Financing Administration (USA). By critical assessment of large number of clinical investigations,the cost-effectiveness of FDG PET scans has been confirmed in the following cases: differential diagnosis of solitary pulmonary nodule, diagnosis,staging and restaging of non-small cell lung cancer, colorectal cancer, malignant lymphomas, melanoma malignum, esophageal neoplasms and cancers of the head and neck. The role of this method in breast cancer is currently under intensive investigation. Due to the correct staging, PET examinations in these indications enable the clinicians to choose the optimal treatment ensuring the maximum probability of recovery and being cost-effective as unnecessary medical interventions become avoidable.

[Cost-effective PET scans in oncology]. / Költséghatékony onkológiai PET-vizsgálatok.

The authors have reviewed the financial considerations of oncological FDG PET examinations by the guidelines of the Health Care Financing Administration (USA). By critical assessment of large number of clinical investigations, the cost-effectiveness of FDG PET scans has been confirmed in the following cases: differential diagnosis of solitary pulmonary nodule, diagnosis, staging and restaging of non-small cell lung cancer, colorectal cancer, malignant lymphomas, melanoma malignum, esophageal neoplasms and cancers of the head and neck. The role of this method in breast cancer is currently under intensive investigation. Due to the correct staging, PET examinations in these indications enable the clinicians to choose the optimal treatment ensuring the maximum probability of recovery and being cost-effective as unnecessary medical interventions become avoidable.

[Diagnostic possibilities of positron emission tomography in oncologic pulmonology]. / A pozitronemissziós tomográfia alkalmazási lehetóségei a tüdógyógyászati onkológiában.

The authors present the possibilities of applying positron emission tomography (PET) in oncopulmonology. In addition to reviewing the literature, they share their own experience obtained during the diagnostic work-up and follow-up of twenty-three patients. The basic indications and the relevant properties of the most frequently used radiopharmaceuticals are discussed. Finally, the authors raise the question of cost-effectiveness of PET-investigations vs. conventional techniques, and suggest possible algorithms to include this non-invasive imaging method in the diagnostic work-up of patients with malignant or benign pulmonary diseases.