For more on breast exams, go to the Susan G. Komen For the Cure website.

There are many things a doctor must learn -- some of them not so nice, but nearly all of them necessary.

One night, during my first month as a doctor at Columbia University Medical Center in New York City, I was nearing the end of a busy shift in the emergency room. I had seen more than 20 patients, admitting some to the hospital but sending several home with a quick remedy, a reassuring word, and a follow-up appointment. Eyeing the clock, I picked up one last chart from the growing stack and walked into the exam room.

The patient (I'll call her Ms. Smith) was in her late 60s, thin, quiet, and sitting primly on top of the gurney, her hands folded in her lap. We exchanged hellos, and when I asked her what had brought her to the emergency room, she said she'd been very tired. I asked about her diet, her sleep habits, and any other symptoms, but she had no other major complaints.

She answered my questions softly but thoughtfully. Many young doctors might have simply gone through the motions with this patient, but since I had a special interest in aging, her fatigue was as important to me as someone else's chest pain. We went through Ms. Smith's short medical history. She took medication for high blood pressure and, every month or so, saw her regular doctor of 15 years so he could monitor it.

Hoping to find something that might spur a diagnosis, I began the physical exam. I didn't ask Ms. Smith to get completely undressed, however. I had several reasons, and only later did I realize that my reasons were actually excuses: Ms. Smith was wearing only a housedress. The exam "room" was not very private -- just a space defined by a curtain. There was no nurse to help her undress and put on a gown. I was trying to save a little time.

As I had been trained, I started working from the head down. So far, so good-until I placed my stethoscope on her chest to listen to her heart. I felt something very firm, even rocklike. I asked Ms. Smith if she was wearing a special bra or back brace. "No," she said. I asked her if I could take a look

What I saw would have shocked any doctor, no matter how many years of training. Her left breast had been completely consumed by a black, bleeding, softball-size tumor.

"How long has your breast been like this?" I asked.

"Three years," she replied, almost apologetically.

"Did you tell your doctor about it?"

Her answer was simple, direct, and tragic: "He didn't ask."

"Did he examine your breast?"

"No," she answered. "He only treats my blood pressure."

Ms. Smith died three months later from Stage 4 breast cancer that had metastasized throughout her body. Her death was likely preventable, and it teaches women and their doctors many valuable lessons.