BBC News' Carey Johnstone: Now she will have someone else to look after her

The plane landed on a runway carved out of ice at the Amundsen-Scott Antarctic base where Dr Jerri Nielsen was working.

To combat the extreme cold, the plane's crew left the engines running while Dr Nielsen was taken on board. A landing was impossible until temperatures rose to above -50C - warm for the time of year.

It is thought the mission was the earliest summer flight to the pole.

The 47-year-old American doctor discovered a lump in her breast in June and has been treating herself with the help of the Internet and radio link-ups with specialists in the United States.

The US military cargo plane flew for three hours to reach the research station - a dome which houses 41 researchers.

Dr Nielsen has been treating herself for three months

The doctor was taken to the McMurdo base on the Antarctic coast for tests.

It is expected she will be transferred to New Zealand and then home when she is fit enough.

Dr Nielsen discovered the lump during the Antarctic winter when 24-hour darkness and extreme sub-zero temperatures made it impossible to land a plane to collect her.

With the winter coming to an end, the LC-130 rescue plane, equipped with skis for landing on ice, set off from New York last week.

It arrived at the McMurdo station on Wednesday, but bad weather prevented it continuing immediately to the South Pole.

The go-ahead was finally given and a replacement doctor was left at the station as Dr Nielsen was taken aboard the rescue plane.

US Air Force Captain Victor Hines said: "The passenger exchange took just 22 minutes."

Click here to see a map of the rescue flight route

Dr Nielsen was the sole physician for the researchers at base - the same station where scientists discovered the hole in the ozone layer over Antarctica in 1986.

She had been treating herself with equipment dropped by a US military plane during an unprecedented emergency flight in July.

However, she was unable to use an ultrasound scanner after it was damaged during the operation.

The National Science Foundation, which runs the base, has refused to comment on Dr Nielsen's medical condition or whether breast cancer had been diagnosed.

Back-up plane

A second LC-130 aircraft had stayed behind at McMurdo Station as a back-up in case the rescue mission ran into problems.

The crews will not normally fly in temperatures less than -50 degrees - below that and the hydraulic and fuel systems are likely to seize up

The South Pole station is physically cut off from the world from February to October.