India’s increasing patient population benefits from operational excellence

An oncology team in Bengaluru, India, explains how they maximize their PET/CT scanner’s capabilities to better serve their increasing oncology patient population. Broadening their use of radiotracers at very low doses while opening new therapeutic and research paths contribute to the center’s operational excellence.

Data courtesy of HCG Cancer Centre, Bengaluru, India   

The number of cancer patients continues to rise in India, increasing the need for PET scans.¹ The HCG Cancer Centre, Bengaluru, in the state of Karnataka, India, felt the pressures of this growing patient demand. While HCG already had two PET/CT systems installed, the center was still finding it difficult to serve the needs of its patient population. Dr. K.G. Kallur, director of molecular imaging and nuclear medicine at HCG, says “All our patients have to undergo PET/CT, whether it is for diagnosis, therapy, monitoring, radiotherapy, or planning. It was becoming difficult for us to schedule patients.”

HCG’s reputation for specialized PET/ CT imaging also drew a wider patient population, partly due to the selection of radiopharmaceuticals available to patients. The most used PET radiopharmaceutical for PET/CT is fludeoxyglucose injection F 18 (FDG) to visualize sugar metabolism in the tissue. At HCG, additional PET tracers are used to visualize biological activities within tissues. As some of these tracers are extremely short lived, the center wanted a fast scanner to deliver the best possible solutions for the patients who travel large distances and for technicians to obtain excellent image quality. In addition, Kallur says “HCG searched for a PET/CT that could offer a larger field of view to cover a larger area of clinical interest and accommodate larger patients.” 

The center ultimately installed Biograph Vision™ PET/CT featuring 3.2 mm x 3.2 mm lutetium oxyorthosilicate (LSO) crystals, 214-picosecond time of flight (TOF), and the Optiso Ultra Dynamic Range (UDR) detector. Besides this playing a crucial role in helping the center manage the increase in the number of scans, Dr. Kallur adds, “Our nuclear medicine physicians and radiologists have the advantage of being able to report cancerous lesions or tumors accurately and quickly, to eventually plan the treatment better, and to achieve the desired clinical outcome for a patient. This is possible because the enhanced imaging techniques provided by Biograph Vision allows us to offer patients an early diagnosis.” He continues, “We can finish the scan faster than before, and we are able to reconstruct the images faster.”

For a diagnostic imaging center servicing diverse clinical needs, it can be a strategic financial advantage and contribute to operational efficiency to combine two independent imaging devices (PET and CT) functions into a single device. The combined device would help reduce operating expenses associated with maintenance, space, and staffing. Technologists and radiologists would gain proficiency in using a single integrated system, eliminating the need for training on multiple pieces of equipment. Because Biograph Vision is a PET system that is integrated with a 64-slice SOMATOM® Definition CT system, Dr. Kallur’s team uses the scanner for dedicated CT-only procedures from 2:30 p.m. until 6:30 p.m., following PET/CT scans in the morning. An average of 60 CT-only cases are performed per week. These include CT-guided biopsy, CT angiography, and CT-guided transarterial radioembolization (TARE).

The center typically performs 35 PET/CT scans per day using Biograph Vision through planned and unplanned appointments. The recent availability of fibroblast activation protein inhibitor (FAPI) has made it possible for the department to also scan patients without prior appointments. FAPI is an investigational PET tracer that targets fibroblast activation proteins expressed in the cancer-associated fibroblasts (CAF). CAFs make up the tumor microenvironment in many cancer types.² More and more studies have shown that FAPI can visualize many types of cancers.^3,4 Dr. Kallur says, “In our country, you see patients come from far off places. Coming to a major city, they will incur a lot of expenses for their stay as they wait for their turn for an appointment. With FAPI, patients walk in, walk out. FAPI is not dependent on patient’s blood sugar levels. Unlike FDG, no prior fasting is required for scans. We also like FAPI because of our unique diabetic problem in our country.” 

Dr. Kallur continues, “For some malignancies, such as hematological malignancies, uterine, and lymphoma, using FAPI is not suitable, but for many patients at the center, FAPI is used. A typical whole-body FDG scan takes 10 minutes while a Gallium 68 (⁶⁸Ga)-labeled FAPI scan takes 5-7 minutes. This allows the department to accommodate walk-in patients (on a ⁶⁸Ga-FAPI scan) without affecting other patients who have scheduled appointments for that day.”

Effective teamwork and workflow contribute to the efficient operations at the center. The center operates from 5:00 am until 6:30 pm. The quality control of the scanner is started manually at 5:00 am and is completed in 30 minutes. The first patient is injected (with FDG) even as the scanner is being calibrated so that the scan can commence at 6:00 am. Two technologists and two nurses who are dedicated to Biograph Vision serve as the central players in managing the scanner workload as well as in contributing to overall departmental efficiency. 

To optimize workflow, the department implemented specific protocols as shown below. Arterial- and venous-phase CTs are done for all patients except for those who cannot tolerate contrast due to other clinical conditions.

The center has access to several tracers, including those based on ¹⁸F, ¹¹C, ⁶⁸Ga, and ¹³N (NH₃). An average of 127 PET/CT scans are acquired on the Biograph Vision PET/CT per week, with the case volume distributed as shown below. To serve their walk-in patients, they have two in-house gallium generators for non-FAPI tracers which require no fasting prior to scanning. 

The scan time for the various tracers and the typical injected doses in each case (all doses are fixed except for obese patients who get a BMIweighted dose) are shown below. Dr. Kallur says, “The physicians and the technologists appreciate the scanner’s precision and sensitivity, which enable short scan times and ultimately provide an improvement in patient comfort, particularly for those who are claustrophobic and/or bed ridden.”

Optimizing the HCG nuclear medicine department’s process using their new PET/CT system has benefitted both patients and hospital operations. More walk-in patients can be scanned, increasing access to care and reducing economic burden for many patients who travel long distances to the center. The availability of different tracers that provide high-quality images allows the center to provide quick and accurate care for its patient population. Dr. Kallur and his team are excited about being able to open new therapeutic and research paths, and then using those paths to benefit more patients.

K G Kallur, MD, has expertise in general nuclear medicine, PET/CT imaging, and his special areas of interest include theranostics and radiopharmaceuticals. He established the nuclear medicine department at HCG in 1996 and has been serving as the director since then. Dr Kallur played a key role in establishing India’s first FDA-compliant cyclotron and PET pharmaceutical unit at HCG. He is a member of the Society of Nuclear Medicine (India). He has authored several national and international publications and presented papers at various conferences around the world.

Noby Varghese and Abhinav Shanker, Siemens-Healthineers, Bengaluru, Karnataka, India.

Ramya Rajaram, Siemens Healthineers, Hoffman Estates, Illinois, USA.