Significantly Low Effective Dose from ¹⁸FDG PET/CT Scans Using Dose Reducing Strategies: "Lesser is Better"

uz Zaman, Maseeh,Fatima, Nosheen,Zaman, Areeba,Zaman, Unaiza,Tahseen, Rabia Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.7

Background: Fluorodeoxyglucose ($^{18}FDG$) PET/CT imaging has become an important component of the management paradigm in oncology. However, the significant imparted radiation exposure is a matter of growing concern especially in younger populations who have better odds of survival. The aim of this study was to estimate the effective dose received by patients having whole body $^{18}F$-FDG PET/CT scanning as per recent dose reducing guidelines at a tertiary care hospital. Materials and Methods: This prospective study covered 63 patients with different cancers who were referred for PET/CT study for various indications. Patients were prepared as per departmental protocol and 18FDG was injected at 3 MBq/Kg and a low dose, non-enhanced CT protocol (LD-NECT) was used. Diagnostic CT studies of specific regions were subsequently performed if required. Effective dose imparted by 18FDG (internal exposure) was calculated by using multiplying injected dose in MBq with coefficient $1.9{\times}10^{-2}mSv/MBq$ according to ICRP publication 106. Effective dose imparted by CT was calculated by multiplying DLP (mGy.cm) with ICRP conversion coefficient "k" 0.015 [mSv / (mG. cm)]. Results: Mean age of patients was $49{\pm}18$ years with a male to female ratio of 35:28 (56%:44%). Median dose of 18FDG given was 194 MBq (range: 139-293). Median CTDIvol was 3.25 (2.4-6.2) and median DLP was 334.95 (246.70 - 576.70). Estimated median effective dose imparted by $^{18}FDG$ was 3.69 mSv (range: 2.85-5.57). Similarly the estimated median effective dose by low dose (non-diagnostic) CT examination was 4.93 mSv (range: 2.14 -10.49). Median total effective dose by whole body 18FDG PET plus low dose non-diagnostic CT study was 8.85 mSv (range: 5.56-13.00). Conclusions: We conclude that the median effective dose from a whole body 18FDG PET/CT in our patients was significantly low. We suggest adhering to recently published dose reducing strategies, use of ToF scanner with CT dose reducing option to achieve the lower if not the lowest effective dose. This would certainly reduce the risk of second primary malignancy in younger patients with higher odds of cure from first primary cancer.

¹⁸FDG Synthesis and Supply: a Journey from Existing Centralized to Future Decentralized Models

uz Zaman, Maseeh,Fatima, Nosheen,Sajjad, Zafar,Zaman, Unaiza,Tahseen, Rabia,Zaman, Areeba Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.23

Positron emission tomography (PET) as the functional component of current hybrid imaging (like PET/CT or PET/MRI) seems to dominate the horizon of medical imaging in coming decades. $^{18}$Flourodeoxyglucose ($^{18}FDG$) is the most commonly used probe in oncology and also in cardiology and neurology around the globe. However, the major capital cost and exorbitant running expenditure of low to medium energy cyclotrons (about 20 MeV) and radiochemistry units are the seminal reasons of low number of cyclotrons but mushroom growth pattern of PET scanners. This fact and longer half-life of $^{18}F$ (110 minutes) have paved the path of a centralized model in which $^{18}FDG$ is produced by commercial PET radiopharmacies and the finished product (multi-dose vial with tungsten shielding) is dispensed to customers having only PET scanners. This indeed reduced the cost but has limitations of dependence upon timely arrival of daily shipments as delay caused by any reason results in cancellation or rescheduling of the PET procedures. In recent years, industry and academia have taken a step forward by producing low energy, table top cyclotrons with compact and automated radiochemistry units (Lab-on-Chip). This decentralized strategy enables the users to produce on-demand doses of PET probe themselves at reasonably low cost using an automated and user-friendly technology. This technological development would indeed provide a real impetus to the availability of complete set up of PET based molecular imaging at an affordable cost to the developing countries.

Controversies about Radioactive Iodine-131 Remnant Ablation in Low Risk Thyroid Cancers: Are We Near A Consensus?

Zaman, Maseeh Uz,Fatima, Nosheen,Padhy, Ajit Kumar,Zaman, Unaiza Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.11

Well differentiated thyroid cancers (WDTC), including papillary (80%) and follicular (10%) types, are the most common endocrine cancers globally. Over the last few decades most the diagnosed cases have fallen into low risk categories. Radioactive iodine-131 (RAI) has an established role in reducing recurrence and improving the survival in high risk patients. In patients with primary tumor size <1 cm, RAI is not recommended by many thyroid societies. However, low risk WDTC has been an arena of major controversies, most importantly the role and dose of adjuvant RAI for remnant ablation to minimize chances of recurrence and improving survival. This review is an attempt to update readers about the previous and existing practice based on results of non-randomized trials and evolving trends fueled by recently published randomized studies.

Design, Control & Performance Analysis of Baby Bot

Hasan U. Zaman,Sharmina Zaman,Baized,Chowdhury,Uddin,Ishaque,Tamim,S. M. Hasibul Hoq,Saad Akash,Saifullah Basher Shohel,Swapnil Sayan Saha,Nazia Nawar Hassan 대한전자공학회 2017 대한전자공학회 학술대회 Vol.2017 No.1

A multipurpose robot is introduced in this research paper. The robot is designed smaller in size and named Baby Bot. Features like household works, rescue mission as a surveillance is specialized in the robot. Control part is designed using Arduino development board. The baby bot can be controlled using android app & Transmitter. Internet protocol camera in fed to check live video feed in rescue missions. Proactive sensors for emergency situation like fire breakout are added and enabled a new dimension in this research. Performance analysis is shown to justify the difference and uniqueness among the conventional robots. The entire analysis part is shown to prove the Baby Bot an efficient, sustainable & affordable robot that can be used both in home and workplaces. This paper also enables the immense possible research scope among home and industrial robots.

Comparable Ablation Efficiency of 30 and 100 mCi of I-131 for Low to Intermediate Risk Thyroid Cancers Using Triple Negative Criteria

Fatima, Nosheen,Zaman, Maseeh uz,Zaman, Areeba,Zaman, Unaiza,Tahseen, Rabia Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.3

Background: There is controversy about ablation efficacy of low or high doses of radioiodine-131 (RAI) in patients with differentiated thyroid cancers (DTC). The purpose of this prospective study was to determine efficacy of 30 mCi and 100 mCi of RAI to achieve successful ablation in patients with low to intermediate risk DTC. Materials and Methods: This prospective cross sectional study was conducted from April 2013 to November 2015. Inclusion criteria were patients of either gender, 18 years or older, having low to intermediate risk papillary and follicular thyroid cancers with T1-3, N0/N1/Nx but no evidence of distant metastasis. Thirty-nine patients were administered 30 mCi of RAI while 61 patients were given 100 mCi. Informed consent was acquired from all patients and counseling was done by nuclear physicians regarding benefits and possible side effects of RAI. After an average of 6 months (range 6-16 months; 2-3 weeks after thyroxin withdrawal), these patients were followed up for stimulated TSH, thyroglobulin (sTg) and thyroglobulin antibodies, ultrasound neck (U/S) and a diagnostic whole body iodine scan (WBIS) for ablation outcome. Successful ablation was concluded with stimulated Tg< 2ng/ml with negative antibodies, negative U/S and a negative diagnostic WBIS (triple negative criteria). ROC curve analysis was used to find diagnostic strength of baseline sTg to predict successful ablation. Results: Successful ablation based upon triple negative criteria was 56% in the low dose and 57% in the high dose group (non-significant difference). Based on a single criterion (follow-up sTg<2 ng/ml), values were 82% and 77% (again non-significant). The ROC curve revealed that a baseline sTg level ${\leq}7.4ng/ml$ had the highest diagnostic strength to predict successful ablation in all patients. Conclusions: We conclude that 30 mCi of RAI has similar ablation success to 100 mCi dose in patients with low to intermediate risk DTC. A baseline $sTg{\leq}7.4ng/ml$ is a strong predictor of successful ablation in all patients. Low dose RAI is safer, more cost effective and more convenient for patients and healthcare providers.

Factors Predicting Early Release of Thyroid Cancer Patients from the Isolation Room after Radioiodine-131 Treatment

Fatima, Nosheen,Zaman, Maseeh uz,Zaman, Areeba,Zaman, Unaiza,Tahseen, Rabia,Shahid, Wajiha Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.1

Background: Patients with differentiated thyroid cancers (DTC) who receive radioactive iodine-131 (RAI) are released from isolation when their dose rate is below the regulatory requirements. The purpose of this study was establish predicting factors for early release from the isolation facility after RAI administration in patients with DTC. Materials and Methods: This was a prospective study which included 96 (58 females and 38 males) patients with DTC who had received RAI from April 2013 till August 2015. The study was duly approved by the ethical committee of the institute. Patients who had complete information of primary tumor size (PTS), serum TSH, stimulated thyroglobulin level [sTg] with antibodies (IU/ml) at the time of RAI treatment were included. All had a normal serum creatinine level. To attain lower effective half-life good hydration and administration of soft laxative were ensured. Dose rate was measured (immediately, 24 h and 36 h) at 1 meter distance from anterior mid trunk and a dose rate <$50{\mu}Sv/h$ was considered as the releasing criterion. At 24 h 50 patients were released while the remaining 46 patients were released at 36 h. A post-ablative whole body scan (PA-WBIS) was performed 5-8 days after RAI ablation in all patients. Results: Patients released after 24 h were significantly younger, had smaller lesions with higher proportion of papillary cancer, lower sTg, lower sTg/TSH ratio and had received a lower dose of RAI as comapred to those who were discharged after 36 h. Serum TSH and gender were not found to have any significant correlation between two cohorts. ROC and multivariate analysis have shown age ${\leq}37years$, PTS ${\leq}3.8cm$, $RAI{\leq}150mCi$, $sTg{\leq}145ng/ml$ and $sTg/TSH{\leq}1.085$ as strong indepedent predictors for early release. Conclusions: We conclude that younger age (${\leq}37years$), smaller tumor size (${\leq}3.8cm$), lower RAI dose (${\leq}150mCi$), lower sTg (${\leq}145ng/ml$) and a lower sTg/TSH ratio (${\leq}1.085$) are significant independent predictors for release at 24 h after RAI treatment in DTC patients. Effective utilization of these factors could help the treating physicians to use limited number of internment facilities with higher throughput, lower cost and lower psychological stress to patients.

Baseline Stimulated Thyroglobulin Level as a Good Predictor of Successful Ablation after Adjuvant Radioiodine Treatment for Differentiated Thyroid Cancers

Fatima, Nosheen,uz Zaman, Maseeh,Ikram, Mubashir,Akhtar, Jaweed,Islam, Najmul,Masood, Qamar,Zaman, Unaiza,Zaman, Areeba Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.15

Background: To determine the predictive value of the baseline stimulated thyroglobulin (STg) level for ablation outcome in patients undergoing adjuvant remnant radioiodine ablation (RRA) for differentiated thyroid carcinoma (DTC). Materials and Methods: This retrospective study accrued 64 patients (23 male and 41 female; mean age of $40{\pm}14$ years) who had total thyroidectomy followed by RRA for DTC from January 2012 till April 2014. Patients with positive anti-Tg antibodies and distant metastasis on post-ablative whole body iodine scans (TWBIS) were excluded. Baseline STg was used to predict successful ablation (follow-up STg <2 ng/ml, negative diagnostic WBIS and negative ultrasound neck) at 7-12 months follow-up. Results: Overall, successful ablation was noted in 37 (58%) patients while ablation failed in 27 (42%). Using the ROC curve, a cut-off level of baseline STg level of ${\leq}14.5ng/ml$ was found to be most sensitive and specific for predicting successful ablation. Successful ablation was thus noted in 25/28 (89%) of patients with baseline STg ${\leq}14.5ng/ml$ and 12/36 (33%) patients with baseline STg >14.5 ng/ml ((p value <0.05). Age >40 years, female gender, PTS >2 cm, papillary histopathology, positive cervical nodes and positive TWBIS were significant predictors of ablation failure. Conclusions: We conclude that in patients with total thyroidectomy followed by I-131 ablation for DTC, the baseline STg level is a good predictor of successful ablation based on a stringent triple negative criteria (i.e. follow-up STg < 2 ng/ml, a negative DWBIS and a negative US neck).

Hybrid Imaging in Oncology

Fatima, Nosheen,uz Zaman, Maseeh,Gnanasegaran, Gopinath,Zaman, Unaiza,Shahid, Wajeeha,Zaman, Areeba,Tahseen, Rabia Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.14

In oncology various imaging modalities play a crucial role in diagnosis, staging, restaging, treatment monitoring and follow up of various cancers. Stand-alone morphological imaging like computerized tomography (CT) and magnetic resonance imaging (MRI) provide a high magnitude of anatomical details about the tumor but are relatively dumb about tumor physiology. Stand-alone functional imaging like positron emission tomography (PET) and single photon emission tomography (SPECT) are rich in functional information but provide little insight into tumor morphology. Introduction of first hybrid modality PET/CT is the one of the most successful stories of current century which has revolutionized patient care in oncology due to its high diagnostic accuracy. Spurred on by this success, more hybrid imaging modalities like SPECT/CT and PET/MR were introduced. It is the time to explore the potential applications of the existing hybrid modalities, developing and implementing standardized imaging protocols and train users in nuclear medicine and radiology. In this review we discuss three existing hybrid modalities with emphasis on their technical aspects and clinical applications in oncology.

Blastocystis hominis : A Brief Review

Zaman, Viqar Medical Publications Korea 1995 Medical Progress Vol.17 No.8

<i>Ca_V2.3</i> Channels Are Critical for Oscillatory Burst Discharges in the Reticular Thalamus and Absence Epilepsy

Zaman, Tariq,Lee, Kyoobin,Park, Cheongdahm,Paydar, Afshin,Choi, Jee ,Hyun,Cheong, Eunji,Lee, C. ,Justin,Shin, Hee-Sup Elsevier 2011 Neuron Vol.70 No.1

<P><B>Summary</B></P><P>Neurons of the reticular thalamus (RT) display oscillatory burst discharges that are believed to be critical for thalamocortical network oscillations related to absence epilepsy. Ca<SUP>2+</SUP>-dependent mechanisms underlie such oscillatory discharges. However, involvement of high-voltage activated (HVA) Ca<SUP>2+</SUP> channels in this process has been discounted. We examined this issue closely using mice deficient for the HVA <I>Ca<SUB>V</SUB>2.3</I> channels. In brain slices of <I>Ca<SUB>V</SUB>2.3</I><SUP>−/−</SUP>, a hyperpolarizing current injection initiated a low-threshold burst of spikes in RT neurons; however, subsequent oscillatory burst discharges were severely suppressed, with a significantly reduced slow afterhyperpolarization (AHP). Consequently, the lack of <I>Ca<SUB>V</SUB>2.3</I> resulted in a marked decrease in the sensitivity of the animal to γ-butyrolactone-induced absence epilepsy. Local blockade of <I>Ca<SUB>V</SUB>2.3</I> channels in the RT mimicked the results of <I>Ca<SUB>V</SUB>2.3</I><SUP>−/−</SUP> mice. These results provide strong evidence that <I>Ca<SUB>V</SUB>2.3</I> channels are critical for oscillatory burst discharges in RT neurons and for the expression of absence epilepsy.</P> <P><B>Highlights</B></P><P>► <I>Ca<SUB>V</SUB>2.3</I> channels are critical for oscillatory burst discharges in RT neurons ► <I>Ca<SUB>V</SUB>2.3</I> channels contribute a major component to HVA Ca<SUP>2+</SUP> currents in RT neurons ► <I>Ca<SUB>V</SUB>2.3</I> channels are required for full recruitment of slow AHP in RT neurons ► <I>Ca<SUB>V</SUB>2.3</I> channels play a critical role in GBL-induced SWDs in mice</P>