In September 2023, Ravi (name changed), a 67-year-old from Bengaluru, developed symptoms of jaundice. Further investigations brought more alarming news: he had an aggressive form of pancreatic cancer with a poor prognosis. A PET scan revealed that the malignant lesion had advanced, complicating treatment.
To treat his jaundice, doctors performed a stenting procedure. Ravi then underwent eight cycles of neoadjuvant systemic chemotherapy to shrink the tumour. This was followed by 27 sessions of external beam radiation therapy (EBRT).
Typically, cancer treatment involves three main approaches: surgery, chemotherapy and radiotherapy, sometimes combined with immunotherapy. Surgery aims to remove all visible cancer. However, microscopic cancer cells that are too small to detect may remain in the area around the surgery site. If left untreated, these cells can grow back, causing the cancer to recur. To address this, radiotherapy is given after surgery to target these residual cells.
In Ravi’s case, despite the treatments he underwent, a followup PET CT scan showed the disease affecting nearby critical blood vessels. Surgery was seen as an inadequate option as it could still leave behind some cancer cells. Pancreatic cancer near major blood vessels is hard to remove completely, increasing the chances of the cancer coming back. Conventional radiation doses, limited to 50-54 Gy, are often not strong enough to treat cancer near vital structures fully.
Conventional radiotherapy has other limitations, too. It involves delivering radiation from outside the body, which means it must pass through healthy tissues―such as skin, fat, intestines or kidneys―before reaching the target area. This can harm normal tissues and still may not reach the intended location with precision, as pinpointing the exact spot of residual cancer deep inside the body can be challenging.
Ravi was in distress. But then Dr Somashekhar S.P., lead consultant in surgical and gynaecological oncology at Aster Whitefield, recommended an advanced Whipple procedure with vessel resection―a complex surgery for treating tumours and other conditions in the pancreas, small intestine and bile ducts. The Whipple procedure involves removing the head of the pancreas, the first part of the small intestine, the gallbladder and the bile duct. Notably, for this procedure, Somashekhar relied on an advanced technology called Intra-operative Electron Radiotherapy (IOERT), which allows for the precise delivery of high radiation doses directly to the tumour site during surgery, minimising harm to surrounding tissues.
Traditional radiotherapy cannot be administered immediately after surgery because the surgical wound needs time to heal―about six to eight weeks. Administering radiotherapy too soon can lead to wound complications and infections. Once the wound heals, the patient undergoes radiotherapy over five weeks, with daily hospital visits. “However, IOERT is a robotic radiotherapy system that allows radiation to be delivered directly to the cancer site during surgery,” says Somashekhar, who is also the global director of Aster International Institute of Oncology - GCC & India.
IOERT is a high-dose electron machine, weighing 500kg, resembling a small robotic arm. “Using a magnet and a cone applicator, the machine delivers radiotherapy directly to the critical area within 35 to 60 seconds,” says Somashekhar. “This process happens during surgery while the patient is under anaesthesia, ensuring maximum comfort. By administering radiation immediately after tumour removal, there is no waiting for cancer to regrow over the next eight weeks, as is often the case with conventional radiotherapy. Notably, this one-of-a-kind technology offers minimal side-effects and reduced recurrence rates because of the high efficacy of localised radiation.” Also, eliminating the need for additional radiation sessions post surgery means patients can save time and money.
“The tumour seemed inoperable,” says Arjun, Ravi’s son. “No one was willing to take the risk in my father’s case. So I went ahead with the radiotherapy option, during which my father received 25 sessions. But then we came to know of the benefits of using the IOERT machine, and I agreed to go ahead with it. The surgery was on August 13, and my father has been recovering well.”
Somashekhar says that such machines were only available in Europe and the US until now. “Aster hospital is the first in India to adopt this technology, and it is only the second or third machine in the Asia-Pacific region,” he says. “Over 50 patients from India and abroad―Singapore, Australia, the Middle East, Africa and Europe―have already been treated with this machine.”
The acclaimed oncologist notes that for recurrent cancers, this technology offers a unique advantage. “Conventionally, a specific area can only be treated with radiotherapy once because of the high risk of side-effects from repeated radiation. However, with IOERT, the same area can be safely treated again,” says Somashekhar. “For example, in rectal cancer, if a patient has already undergone radiotherapy and the cancer recurs, conventional radiation cannot be administered again because of the risks. IOERT allows repeat radiation safely and effectively. Similarly, for breast cancer patients undergoing breast-conserving surgery, a single dose of IOERT during surgery can eliminate the need for additional radiation sessions, enabling breast preservation without further treatment.”
Experts emphasise that precision is paramount in cancer treatment today, and that innovative technologies are revolutionising the efficiency of conventional radiation therapies. Dr Suneetha N., consultant, radiation oncology at Aster Whitefield, says that surface-guided radiation therapy (SGRT) is one such new technique.
“SGRT is used to map the patient’s surface to enhance precision during radiation treatment,” says Suneetha. “Precision has to start with preparatory procedures like immobilisation. Since radiation is administered over multiple sessions, it is vital to position the patient consistently in the same way as on the first day. Traditionally, this was achieved using masks or vac-locks―customised beanbag-like devices―to reproduce the patient’s position daily. With SGRT, however, the process has become more advanced and accurate.”
Suneetha explains that as a part of this process, a detailed surface image of the patient’s contour is captured, and each day during treatment, this image is displayed on the machine and superimposed over the initial reference image. “Any discrepancies in positioning are highlighted in real-time. For instance, if a body part, such as the hand, is misaligned, the system projects a red light on to the patient’s body at the mismatched area,” she says. “Adjustments can then be made until the red light disappears and is replaced by a neutral indicator, such as a blue light, confirming correct alignment. This technology ensures precise and reproducible patient positioning, improving the accuracy and effectiveness of radiation therapy.”
Suneetha notes that SGRT also offers real-time monitoring during treatment. Cameras installed in the machine continuously track the patient’s surface, and if movement exceeds a set limit, the radiation beam automatically stops. This minimises errors caused by involuntary movements like coughing or sneezing.
One of SGRT’s significant advantages is in treating left-sided breast cancer, where the heart and lungs risk radiation exposure, says Suneetha. Using Deep Inspiration Breath Hold technology, SGRT ensures that treatment occurs only when the patient’s breath holds within a specified range, reducing radiation to critical organs. This approach enhances safety and efficacy, allowing precise, uninterrupted treatment sessions. Integrated into linear accelerators like the Versa HD, SGRT represents a significant leap forward in cancer care.