When the American Cancer Society’s fifth annual Relay for Life begins this afternoon, more than 400 walkers will take over the track at the Martha’s Vineyard Regional High School in Oak Bluffs to support patients in treatment for cancer, survivors of the disease and to honor the memory of those lost along the way.

The walking begins at 3 p.m. and continues through the afternoon with live music and hamburgers grilled by the Martha’s Vineyard Rotary Club. As evening falls, survivors will do a special lap and luminaries will be lit to honor those who have battled the disease. With the stars overhead, comedian Marty Nadler will crack jokes and marshmallows will be roasted over a campfire. All the while, members of the 33 registered walking teams will be making their way around the track.

They will walk on through the night and into the morning. They will not stop until noon on Saturday.

The relay, which has grown tremendously in its short history, raises money for the American Cancer Society, a national organization. Although the organization is countrywide in scope, it is a cause which is painfully local.

“As Islanders, we are so impacted by cancer,” said Katheryn Yerdon, event chairman. “There is no cure and there won’t be unless someone is actively looking for it. The best way for us as Islanders to help is to raise money. We’re never going to get ahead of it if we don’t fund it.”

In 2003, the first year it was held, the relay raised $25,000 to fund cancer research. Last year, that figure was $100,000. This year, the group hopes to raise $125,000.

“We have one of the highest rates of cancer anywhere in the country,” Ms. Yerdon said. “Massachusetts and the Cape and the Islands have one of the highest rates. There is not one person on the Island who has not been touched.”

This year, one of those touched decided the Vineyard could do even more to support the cause. For the first time in its history, a bone marrow donor drive will occur at the same time as the relay.

On Friday evening between 6 and 8:30 and again on Saturday morning from 8:30 to 11, representatives from the Dana-Farber Cancer Institute in Boston will screen potential donors in the high school parking lot. The screening is quick — it takes about 15 minutes — and painless. A self-conducted swab inside the cheek and a short set of medical questions are all it takes.

The results could change a life. “It only takes one person to save a life,” said Diane Gemba, a recruitment coordinator at Dana-Farber who will run the drive this weekend.

The idea for the Island drive came about only last week. In March, a local cancer patient who wishes to remain anonymous learned the leukemia he was first diagnosed with in 2006 had returned. He is now undergoing radiation treatment to try to beat the cancer, but what he needs is a bone marrow transplant.

For many patients with leukemia, lymphoma and other life-threatening diseases, a transplant is the best — sometimes the only — hope for a cure. Because of this, the demand for transplants is large. On any given day, more than 6,000 men, women and children search the National Marrow Donor Program registry.

Those who stop by the drive at the high school this weekend will be entered into the program registry database. Donor marrow must match the patient’s own marrow as closely as possible, so increasing the number of donors and their diversity is important. Donors must be between the ages of 18 and 60, meet certain health guidelines and be willing to donate to any patient in need. Once in the registry, potential donors will remain on the list until age 65.

Last week, the Island patient contacted Ms. Gemba at Dana-Farber to ask whether a bone marrow drive could take place on the Vineyard this weekend. Drives are usually set up four to six weeks in advance and Ms. Gemba was scheduled to begin her annual vacation on Friday, but for this occasion and this patient, she made a special exception.

“He thought this was a good time to have it and there would be a captive audience,” she said. “He was very passionate about the drive and was very passionate about the cause.”

Two years ago, the man who made the phone call was in perfect health. And then one day, at age 47, he cut himself and could not control the bleeding. A test at the Martha’s Vineyard Hospital confirmed he had leukemia.

He checked into Rhode Island Hospital, where he stayed for seven weeks and received regular chemotherapy treatments. Afterwards, he went into a maintenance program and things looked good. Then, in March, he noticed a lump on his ear. The leukemia was back. Even after several rounds of radiation, new spots kept popping up. He is now undergoing chemotherapy in hopes that he will go into remission and be strong enough to receive a transplant, if a donor can be found.

More than 35,000 people are diagnosed each year with illnesses that could be treated with a bone marrow transplant. Thirty per cent of those in need find a donor match within their family. The remaining 70 per cent rely on donors: friends, neighbors or people on the other side of the country whom they will never meet.

“There’s thousands of people who are waiting on a daily basis for a match,” the Vineyard patient said. “But I’ve learned percentages are just percentages. As long as there’s one per cent, there’s always a chance. It’s been an up-and-down battle. I really thought we beat it after the initial program and then the maintenance program and I was shocked, my wife was shocked, our family friends were shocked when I was rediagnosed. But yes, I am very hopeful.”

If this drive does not help him directly, the patient hopes it will help someone.

“It’s something very simple and simply done,” he said. “It’s a life-giving opportunity to give to somebody, to myself or to thousands of others who are waiting.”

On Friday, this man will be found making his way around the high school track, as he did the year before. With him will be his wife and his daughter. His friends will be there as will nurses who have treated him.

“These are people who have been part of my team, which to me is an honor,” he said. “They’ve taken care of me and given me stability and support. After all this, the most important thing is having a support team to get through this. Doing this alone is impossible.”