ANTARCTIC DOCTOR TO TREAT SELF.

Byline: Denise Grady The New York Times

Winter temperatures at the Scott-Amundsen research station at the South Pole average 80 degrees below zero Fahrenheit, and it is pitch dark nearly 24 hours a day. People who sign on to work there understand that they will not see home for a long time.

From February to October, planes cannot even land.

But an Air Force jet came close Sunday, dipping low over the base at 2 a.m. to drop medical supplies for a woman, trapped there for the winter, who discovered a lump in her breast and needed treatment.

Her plight turns out to be even more complex than initial reports suggested. The woman herself is the only medical doctor at the station, according to a cancer expert who was consulted in her case and spoke to The New York Times on condition of anonymity.

So the woman must act as her own doctor and, if the lump is malignant, administer any needed treatment, which might include chemotherapy.

The consultant said he thought the woman would perform her own biopsy and might already have done so. Although the thought of driving a needle into one's own breast to look for cancer cells might horrify most people, ``I would assume that somebody who chooses to go to the South Pole is a tough person, a strong character,'' he said. ``It wouldn't shock me that somebody could do this.''

If she becomes incapacitated, 40 others in the research team will be left without a doctor at the remote Antarctic outpost.

Dr. Karl Erb, director of the Office of Polar Programs at the National Science Foundation, which runs the base, declined to identify the woman or confirm she is the station's doctor. Erb said cancer experts in the United States have made a working diagnosis, but he declined to reveal whether a biopsy has been performed. He said she was expected to start using the dropped supplies immediately.

Erb said the foundation is honoring her request for confidentiality and will not reveal whether she has cancer.

Mary Hanson, a spokeswoman for the foundation, said officials decided, however, that the public had the right to know there was an Air Force medical-drop mission.

``We knew it was going to get out sooner or later, so it seemed appropriate to explain as much as we could as soon as we could,'' she said.

Erb also said it is adequate to have one doctor at an Antarctic station, backed up by people with paramedic training, along with computer, video and telephone links to medical centers. In addition, he said, people who sign up for extended stays at the South Pole are carefully screened for medical problems.

``Everyone there is sufficiently fit that he or she is carrying out assigned duties without any problem,'' he said.

Hanson said the woman, who is 47, had been working at the station since December and discovered the lump in her breast in June. Foundation officials sought advice on her behalf from doctors at the National Cancer Institute and other cancer centers.

``The patient and her physicians decided on a course of drug treatment that they consider appropriate to maintain her health and safety,'' foundation officials said in a joint press release. But the press release did not specify what the treatment would be. Erb said supplies were sent in for several different treatment options.

He said the jet zoomed in low over the base and dropped the equipment from an altitude of about 700 feet.