When Ms Michelle Mak discovered she had a nodule in her thyroid gland in 2015, she was hesitant to have surgery to remove it as the procedure was likely to leave a 6cm scar across her neck.

But when offered a chance to have a new scar-free operation in December that year, she decided to take it up. By then, the lump had grown to about 4cm and was visible through her neck.

“I decided to take the lump out because, otherwise, I would have had to live with it for the rest of my life,” said Ms Mak, 26, who works in the banking industry.

In January last year, she went under the knife to have it removed. She is among over 20 patients to have had scar-free surgery at Singapore General Hospital (SGH) since it was introduced in late 2015.

Lumps in the thyroid affect about 7 per cent of the population, with women being four times more likely than men to be affected.

Such lumps are mostly benign and do not affect everyday life, but some grow into a clear bulge in the neck and can cause shortness of breath or difficulty in swallowing. About one in 10 lumps found is cancerous.

As a significant number of those diagnosed with thyroid lumps are young women, patients are often anxious about scarring after surgery, said Dr Jeremy Ng, head and senior consultant at the Department of General Surgery at SGH.

But this scar-free procedure, known as transoral endoscopic thyroidectomy, is the least invasive among existing types of thyroid surgery here. Instead of operating through the neck, chest or armpit, as in other types of thyroid surgery, the surgeon goes through the patient’s inner lower lip, which hides any wounds.

The entire procedure takes two to three hours. Patients tend to stay in hospital for two to three days.

Even though conventional thyroid surgery takes less time, lasting one to two hours, and has a low complication rate, it can leave a visible scar across the neck. Other surgical options leave scars on the chest or armpit, and could cost as much as $10,000.

The transoral method costs about $2,000, after subsidies, for a patient in a Class B2 ward – similar to the costs for conventional surgery.

After surgery, Ms Mak had swelling in the neck and chin area and could not talk for two weeks, which is common with the procedure.

“I couldn’t really see the scars. When I pulled open my lower lip, all I could see were surgical threads,” said Ms Mak, who was in hospital for three days.

As the procedure is still relatively new in Singapore, Dr Ng said it is offered to patients with no previous neck or thyroid surgery and a lump no bigger than 3cm. Patients who are obese, or have a large thyroid or advanced thyroid cancer are not suitable for the procedure.