核医学与放射治疗

Background: During the follow-up of differentiated thyroid cancer patients, the presence of thyroglobulin antibodies makes thyroglobulin measurements unreliable. For this reason, thyroglobulin antibodies measurement and the evaluation of their titer trend are also recommended. Objective: We aimed to identify the best method among stimulated thyroglobulin, thyroglobulin antibodies titer trend, neck ultrasound and diagnostic whole body scan for detecting the presence of disease in a group of differentiated thyroid cancer patients with thyroglobulin antibodies. Patients and methods: We retrospectively reviewed the data of 212 consecutive differentiated thyroid cancer patients with thyroglobulin antibodies referred to us between 2005 and 2007 for performing a diagnostic whole body scan. All patients were evaluated during the first two years after the initial treatment. Results: Diagnostic whole body scan sensitivity and specificity in detecting persistent diseases were 70% and 72%, respectively. Diagnostic whole body scan alone had the best positive and negative predictive values (93% and 32%, respectively). A low sensitivity and specificity (56% and 10%, respectively) for increasing or stable thyroglobulin antibodies titer trends were also identified. A good compromise between sensitivity and specificity was obtained when diagnostic whole body scan, stimulated thyroglobulin and neck ultrasound were combined without considering thyroglobulin antibodies trend evaluations (82% and 45%, respectively). Conclusions: Diagnostic whole body scan plays an important role in detecting persistent disease in differentiated thyroid cancer patients with thyroglobulin antibodies, both alone and in association with other methods. However, its low negative predictive value suggests that when a suspicious persistent disease is present, the use of other imaging methods, such as computed tomography scan or FDG-positron emission computed tomography, is recommended. Finally, from this study, it appears that the thyroglobulin antibodies titer trend does not add any useful information about the disease status in the first two years after initial treatment.

Leakage (peripheral dose) of current radiation devices used in treating tumors could have significant side effects on patients’ quality of life and life span after radiation treatment. A novel design of sandwich radiation shields is being developed at the present time. This design would provide a unique and adaptable device in shielding danger peripheral radiation reaching healthy organs. The present research aims at determination of attenuating properties of the proposed composite radiation shields using experimental, analytical and numerical simulated techniques. The present work indicates that any of the evaluation techniques could be used successfully with the future development of radiation shield design. The results reveal that the filler material thickness of the composite shield has the strongest effect on the shielding capability of the design. Shell material type and thickness have very little effects on the shielding capability and should only be considered for their load carrying capacity and manufacturability by 3-D printing techniques.

Background: Radionuclide shuntography is a safe, simple and non-invasive functional imaging technique for determining ventriculo-peritoneal (V-P) shunts tube patency with minimal radiation exposure. This is particularly useful in children with hydrocephalus in whom V-P shunt is inserted to divert CSF drainage. V-P shunts are, in many cases, permanent treatment option for children with hydrocephalus and radionuclide shuntography is becoming a very popular technique because of the increasing numbers and survival of children with shunt-treated hydrocephalus. Objective: The aim of this study is to document the usefulness of shuntography in the evaluation of V-P shunt in patients with hydrocephalus. Materials and Methods: All shuntograms performed in our institution from 2008 to 2015 were included in this study. Radionuclide shuntography was performed with Tc-99m DPTA injected into the shunt reservoir and images acquired using a dual headed MEDISO camera. A normal shuntogram is considered as free flow of radiotracer (Tc-99m DTPA) from site of injection to the distal end of shunt tube and spillage into the peritoneum. Results: A total of 56 children were studied comprising of 32 males and 24 females with age ranges of 5month to 11years. Different patterns of results were found, normal functioning shunt tube, partial block shunt tube due to infection or inflammatory debris and total blocked shunt tube due to mechanical defects. Conclusion: About 52% of our patients had partial blockage of their shunt tube. Patients who are diagnosed with a partial tube blockage will require only flushing of the tube and antibiotics treatment, while mechanically blocked tube will require shunt revision. This distinction is critical considering the cost of replacement of V-P shunt tube and the manpower time for surgery. There was no mortality or morbidity associated with radionuclide shuntography in our patients.

The cancer is a disease of cell in which the normal mechanism of the control of growth and proliferation has been altered. Annually, nearly 3 million people die of cancer in India. The Indian Council of Medical Research said in 2016 the total number of new cancer cases is expected to be around 1.45 million and the figure is likely to reach nearly 1.73 million new cases in 2020. Over 0.736 million people are expected to succumb to the disease in 2016 while the figure is estimated to shoot up to 0.88 million by 2020. Data also revealed that only 12.5 percent of patients come for treatment in early stages of the disease. Purpose: The Purpose was to educate the patients with Head and Neck Cancer undergoing radiation therapy about management of side effects to improve their quality of life. Method: A Quantitative research approach with Quasi-experimental pre-test post-test design. The study was conducted in selected Cancer Research Institute, Dehradun, Uttarakhand. Consecutive sampling technique was used for data collection from 60 Head and neck cancer patients by using Structured Knowledge interview schedule, structured self-reported practice checklist and EORTCH & N35 QLQ. Result: The mean post-test knowledge score in experimental group was 18.70 ± 3.06 which was significantly higher than the control group 11.50 ± 5.00. The mean post-test practice score in experimental group was 16.40 ± 1.86 which was significantly higher than the control group 10.00 ± 3.01. There was significant improvement in the Quality of Life of the patients in experimental group in different phases of radiation therapy. In multiple item scales- Pain (0.014 on 8th day and <0.001 on 16th day), swallowing (<0.001 on 16th day), sense problems (0.019 on 8th day and 0.020 on 16th day), speech problem (0.058 on 8th day and 0.041 on 16th day), social contact (0.005). In single item scale teeth (0.019 on 8th day), opening mouth (<0.001 on 16th day), dry mouth (<0.001 on 16th day), sticky saliva (0.040 on 8th day and <0.001 on 16th day), felt ill (0.017 on 16th day). Moderately positive correlation was found between post-test knowledge & practice score. Conclusion: The instructional strategy was effective in increasing knowledge, practice of Head and Neck cancer patients and also improving their Quality of life.

The aim of this work was to present a theoretical analysis of how phantom dimensions and tissue heterogeneities in interstitial brachytherapy affect on dose distributions. This work was carried out using Gafchromic film measurement and Monte Carlo simulation for 192Ir source. Results show that treatment planning systems (TPS) which consider the patient geometry as homogeneous medium, lead to a dose underestimation up to 8.2% for lung and an overestimation up to 9% for bone. These values depend on the thickness and distance from the source. Thus, TPSs currently in use for clinical brachytherapy cannot consider the effect of tissue heterogeneity on dose distribution.

With the lightest ions beyond protons, i.e., Helium, Lithium and Beryllium ions, highly specific Molecular Bragg peak radiation therapy of malignant tumors is possible with minimal adverse normal tissue reactions elsewhere in the body. The Bragg peak ionization density is only elevated in a few mm wide spot at the end of the ion range with resultant increased local apoptosis and senescence. By only placing Bragg peaks in the tumor, an increased local therapeutic effect is obtained with only low ionization density and easily repairable damage in surrounding normal tissues. A geometrical accuracy in dose delivery of about 1 mm is possible with these ions, and high-resolution molecular tumor imaging is then needed to accurately delineate the target volume. It is proposed that ultra-sensitivity whole body PET cameras should be built to achieve mm resolution in the whole target region. With about 1 m axial field of view an almost 50-fold increased sensitivity and a reduced imaging time down to a few minutes should be in reach. To get sub mm resolution with whole body spectroscopic MR, about 15 Tesla to 20 Tesla is needed and will significantly increase the resolution with tumor specific metabolite imaging from the 10 mm to 15 mm available today. In the future, it should also be possible to achieve a resolution as high as 10 μm with Stereoscopic Phase Contrast X-ray imaging, or to reduce the dose and imaging time by using 2 projections instead of 400 to get 3D images, thanks to the significantly increased contrast in each projection. When these new methods are brought into clinical use together with light ion therapy a mean tumor cure as high as 80% should be possible, and even more if the new early tumor detection and malignancy estimation methods are brought into more regular clinical use.

Purpose: In the quest for novel treatment against safe life form, the alteration of existing medication by mix to a metal focus has picked up consideration as of late. Thus, metal-based drug is seen as promising alternatives for possible replacement for some of the current drugs. So, we synthesized Schiff base metal complexes in this regard. Materials and Methods: A series of transition metal(II) complexes of new Schiff base were synthesized by the condensation of sulphadizine and 2-carboxybenzaldehyde in ethanol. Results: The Schiff base and transition metal complexes were characterized by using different instrumental techniques like microanalysis, thermogravimetric analysis and spectroscopy. The synthesized ligand and metal complexes were subjected to antibacterial studies. The studies showed the enhance activity of metal complexes against one or more species as compared to the uncomplexed ligand. Conclusions: The data showed that transition metal complexes have significant improved antibacterial activity than parent drug.

Purpose/Objective: The prognostic value of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) has not yet been defined in locally advanced esophageal cancer (LAEC). This study aims to elucidate the prognostic role of PET/CT for patients treated with neoadjuvant chemoradiation (CRT) followed by esophagectomy. Materials/Methods: We retrospectively evaluated patients with LAEC treated from 2006 to 2014 with neoadjuvant CRT followed by esophagectomy. A 76 patients had pre-CRT and post CRT PET/CT scans. PET parameters maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), peak standardized uptake value (SUVpeak), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were recorded for both pre-CRT and post-CRT scans. The correlation of the measured parameters with pathologic complete response (pCR) and clinical outcomes was analyzed. Results: Receiver operating characteristic (ROC) analysis was performed to determine the optimal cutoff values for predicting pCR. Binomial logistic regression using these optimal cutoff values was performed for pCR. A pre CRT MTV <33.1 was 4 times more likely to have a pCR (OR 4.20 95%CI 1.60 to 11.0, p=0.004). Pre CRT TLG <153 was 4.7 times more likely to have a pCR (OR 4.71 95%CI 1.78 to 12.4, p=0.002), and post CRT TLG <53.1 was 4.5 times more likely to have a pCR (OR 4.52 95%CI 1.60 to 12.7, p=0.004). On MVA, pre-CRT MTV and pre CRT TLG remained significant (p=0.006 and p=0.039, respectively). Percent change in MTV independently predicted for OS (p=0.034). By contrast, SUVmax and SUVpeak did not predict for pCR or survival. Conclusions: Pre CRT MTV and pre CRT TLG were independently predictive of pCR, and percentage change in MTV independently predicted for OS in LAEC. Further study is needed to determine if MTV and TLG values can help define which patients will most benefit from radiation dose escalation and esophagectomy