The baby had a very large abdominal swelling which his father noticed when he was two-months old. (File)

Doctors have successfully removed a rare abdominal tumour weighing 750 gms from the stomach of a seven-month-old baby from West Bengal.

The baby suffered from a congenital anomaly -- Fetus in Fetu (FIF) -- in which a mass of tissue resembling a fetus forms inside the body. According to the medical literature, FIF is an extremely rare occurrence in India.

The patient Abhir Mondal, a premature baby, had a very large abdominal swelling, which his father noticed when he was only two-months old. After initial treatment in Kolkata, the family went to Bengaluru for further treatment.

After over a month long treatment in Bengaluru, the family is happily back to Kolkata. On Thursday, the doctors who treated the baby accompanied the family from Bengaluru to Kolkata and met the press to give details of this rare medical case.

Married for six years, the baby's parents Tanmoy and Bijiya Mondal are wall design artists, settled at Shantiniketan in West Bengal's Birbhum district.

"When Bijiya was pregnant, she underwent regular tests and scans, which did not detect any abnormalities with the baby. However, the baby was born premature in the seventh month of pregnancy and when Abhir was two months old, his father suspected an abnormal swelling in the abdomen. A doctor from Kolkata then detected an abnormal tumour and congenital anomaly," C. N. Radhakrishnan, head of the department and consultant, Pediatric Surgeon & Urologist, Manipal Hospital, told mediapersons.

The parents travelled to Bengaluru with the baby last month, and after Radhakrishnan examined him, he was stunned to discover the tumour was made of liquid and solid elements including bones.

"The parents came to me in a very anxious state as they were unable to understand the strange condition of the baby, who had a very large tumour arising from the posterior abdominal wall and extending anteriorly."

"I could see that there was a mix of both liquid and solid elements inside the abdomen. These masses are referred to as teratomas, which means that they are composed of tissues not normally present at that site."

"These are thought to develop from germ cells, which are cells that can change into and divide to form any organ in the body. This resembled a very rare condition known as Fetus in Fetu," he said.

The stomach, pancreas and the major blood vessels supplying the intestine were also displaced and had close proximity to the tumour.

"It took careful and meticulous dissection to finally separate the tumour from the rest of the body organs. Careful examination revealed some peculiar facts as the specimen had a sac filled with fluid in which solid components were present, including brain, hair, intestinal tissue and bones, almost giving the appearance of an incompletely formed Fetus," Radhakrishnan said.

Abhir started recovering within seven-ten days after the operation. "He is now fine, and like any other normal child of his age. He is also gaining normal weight," he said.