For people diagnosed with early tongue cancer, one of the biggest questions is often hidden from scans: Has the cancer already reached the lymph nodes in the neck? That question is crucial because it means cancer cells have broken away from the original tumour and travelled through the lymphatic system to nearby lymph nodes, indicating a potential spread and relapse.Doctors at a Mumbai hospital are using a procedure that can help answer that question without subjecting every patient to an extensive neck operation. In a series of 75 patients with early tongue cancer, 70 were able to avoid a full neck dissection after undergoing a procedure called sentinel lymph node biopsy.What is sentinel lymph node biopsy?It is a procedure in which doctors remove and test the first lymph node that cancer cells are most likely to reach from the original tumour. In simple terms, it is a way of checking the “first stop” for cancer to see whether the disease has started spreading to the lymph nodes. If that node is clear, patients may be able to avoid removing many more lymph nodes. If cancer is found there, doctors can consider more extensive treatment.Five patients were found to have cancer in the lymph nodes and underwent a neck dissection during the same operation.The cancer that scans may missOne of the challenges with early tongue cancer is that the neck can appear completely normal even when cancer cells have already travelled there. “Lymph nodes can look completely clear on examination and scans, yet the cancer may have already spread there at a microscopic level,” said Dr Mandar Deshpande, Head, Head and Neck Oncology, Surgical Oncology, Kokilaben Dhirubhai Ambani Hospital.Also Read | ‘Don’t want to give up’: Cancer patient’s fight for Rs 80,000-a-month medsWhy avoid neck dissection if possible?Traditionally, some patients with early tongue cancer undergo neck dissection even when there is no obvious evidence of cancer in the neck.The operation involves removing lymph nodes from several areas of the neck. While it can be necessary when cancer has spread, it is still a major procedure and can cause problems such as neck pain, numbness and stiffness, as well as difficulty moving the shoulder. It can also leave a larger scar and require a longer hospital stay, depending on the extent of surgery and recovery.Story continues below this ad“Only around 10 to 20 per cent of these patients actually have cancer in the lymph nodes,” Dr Deshpande said. “That means the large majority are undergoing a significant operation they did not need.”How does the new procedure work?The process begins with a small injection of a radioactive tracer into the tongue. Imaging then tracks the path taken by the tracer and identifies the lymph node it reaches first.During surgery, doctors locate this sentinel node and remove it through a relatively small incision. The tissue is then examined to look for cancer cells, with an intraoperative test allowing doctors to get a preliminary result in about 30 minutes. If cancer is detected in the sentinel node, the surgical team can proceed to a full neck dissection during the same operation.If the node is clear, the patient can avoid the more extensive surgery.Story continues below this ad70 patients avoided extensive surgeryThe procedure was introduced at the Mumbai hospital in 2023. Since then, it has been performed in 75 patients, according to Dr Deshpande. About 93 per cent of the patients in this series avoided the extensive neck operation. The hospital’s clinical findings also reported an average neck incision of about 3 cm and an average hospital stay of 4.5 days for patients undergoing the sentinel node approach.The smaller operation may reduce surgical trauma and help patients return to normal neck and shoulder movement and routine activities sooner, doctors said.Also Read | She blamed hair loss, gas and low ferritin on different things. Then doctors joined dots, found gut bacteriaA more targeted approach to cancer surgerySentinel lymph node biopsy is not an experimental concept. The approach has been evaluated internationally, including in randomised controlled trials in Japan and Europe, and has been shown to provide outcomes comparable with conventional treatment in appropriately selected patients, according to Dr Deshpande.But the technique is not available everywhere.It requires specialised equipment, nuclear medicine imaging and expertise in examining the lymph node tissue. It is, therefore, currently available only at a limited number of centres in India.Story continues below this adFor doctors, however, the principle behind the procedure is straightforward: not every patient needs the same amount of surgery. The aim is to treat the cancer adequately while preserving as much normal function as possible.