Chinese doctors use microwave energy to destroy fetal lung tumour in the womb, marking a world first

Chinese doctors have shrunk a potentially fatal lung tumour inside a baby still in the womb using only a needle and microwave energy -- without making a single incision -- in what they are calling a world first.

The baby had developed a condition called congenital pulmonary airway malformation (CPAM), a genetic lung abnormality occurring in roughly 1 in 25,000–35,000 pregnancies, reports The Independent.

While usually manageable, severe cases can see the tumour grow rapidly, compressing the heart and lungs and potentially causing fetal death.

At 22 weeks of gestation, the tumour had grown to 5cm and dangerous fluid had begun building up in the baby's abdomen.

Doctors inserted a needle through the mother's abdomen directly into the tumour and used microwave energy to vibrate water molecules inside the abnormal tissue, generating intense heat that destroyed it from within.

Within three days, the tumour had shrunk significantly and the fluid build-up had completely cleared.

The baby was delivered healthy at 37 weeks via caesarean section, weighing 2.9kg.

The case, published in the journal Ultrasound in Obstetrics & Gynecology, marks the first reported use of microwave ablation for fetal CPAM, according to The Independent.

Doctors described it as a "new milestone" but cautioned that its safety and effectiveness could not be confirmed on the basis of a single case.

Existing treatments for severe CPAM include steroid drugs, surgical drainage tubes and fetal lobectomy -- an open-uterus operation with a survival rate of around 50 percent.