"Pray," said the elderly woman as she tucked several vials of the banned supposed anti-cancer drug Laetrile into her handbag for an illegal trip across the border. "Pray that God will stay with us until we get across."

The woman, a cancer patient whose doctor told her recently she has less than a year to live, climbed into a car with two other elderly women and headed back toward the U.S. Customs station at the California border. They looked more like a returning bridge club than a trio of drug smugglers.

Every morning hundreds of cancer patients or persons with relatives dying of the disease gather in this border town for what many consider a life-or-death smuggling run to sneak the drug, which is made from apricot pits, into the United States, where it is banned as useless.

The cars carry license plates from as far away as Canada and Alaska, or the Laetrile seekers arrive in a fleet of small bright yellow minibuses that [WORD ILLEGIBLE] here daily from motels in San [WORD ILLEGIBLE] just across the border, that [WORD ILLEGIBLE] cancer patients.

[WORD ILLEGIBLE] smuggling has turned into [WORD ILLEGIBLE] siness on the Mexican border. [WORD ILLEGIBLE] Herbert Hoffman, an [WORD ILLEGIBLE] attorney in San Diego who [WORD ILLEGIBLE] a major Laetrile smuggling case there, said customs officials are seizing the equivalent of 40,000 three-gram vials of the drug monthly, making it the second biggest U.S. smuggling problem after narcotics.

"Slick promoters have gotten into this thing recently and they are making big money on Laetrile," said Wayne Pines, a spokesman for the Food and Drug Administration in Washington. The FDA is waging a vigorous campaign against Laetrile. "This stuff," said Pines, "has a higher markup than heroin."

In theory, Laetrile, known chemically as amygdalin, words this way:

When introduced into the body, Laetrile is split by a natural enzyme to release several substances, including cyanide. The theory holds that cancer cells contain more of the enzyme than normal cells and thus get more cyanide and are killed. At the same time, normal cells are held to contain an enzyme that neutralizes the cyanide.

The FDA claims Laetrile is illegal under provisions of the U.S. Food, Drug and Cosmetic Act. Alaska is the only state which permits its use, but Laetrile legalization laws are before legislatures in Indiana, Nevada, North and South Dakota, California, Louisiana, Mississippi and Florida, according to Frank Solomon, a San Francisco businessman who is vice president of the Committee for Freedom of Choice in Cancer Therapy.

Sixteen persons are now charged by the Justice Department with being involved in a Laetrile smuggling conspiracy. Four of the 16 are being tried in federal court in San Diego on the felony charge.

That smuggling case is one of two that are being closely watched by advocates and opponents of Laetrile as bellwether decisions on the future of the drug in the United States.

The second case involves a class-action suit filed by Laetrile advocates against the FDA in U.S. District Court in Oklahoma City. In a memorandum of opinion last month, U.S. District Court Judge Luther Bohanon ordered the FDA to come up with proof within 120 days that Laetrile should fall under the provisions of the food, drug and cosmetic law.

Bohanon noted that while Laetrile's cancer-curing status remains controversial, "depriving a terminally ill cancer patient of a substance he finds therapeutic, whether such benefit is physical or psychological, creates a very real risk that irreparable injury might be sustained." The judge granted several cancer patients temporary permits to go to Mexico and bring back Laetrile for their own use.

The fight over Laetrile has taken on highly emotional overtones on both sides recently. Federal opponents, such as the FDA, and the American Cancer Society and big drug companies which oppose the substance have called it "a cruel hoax," and say that tests going back to 1957 show it has no effect whatsoever on cancer.

Equally adamant - and rapidly becoming more vocal - are the Laetrile advocates who have taken on the cause of the drug not only as a cancer cure but as a case against government intervention in private affairs.

"Whether Laetrile works or not is beside the point," said Solomon. "It's up to the individual to make his own choice, not the government to tell him how to conduct his doctor-patient relationship."

The committee, one of the most vocal advocates of legalization of Laetrile, has grown recently to 400 chapters and thousands of members, according to Solomon. Committee members and other advocates have besieged members of Congress recently with letters urging that Laetrile be made legal. Solomon and other committee officials are among those charged by Justice with Laetrile smuggling.

But the legal battle over Laetrile does not seem to intrude on the gathering of the cancer victims who have come here to obtain the drug.

One of the two private medical facilities here that dispense Laetrile, which is legal here and controlled by the Mexican government, is the Del Mar Clinic. There is a somewhat grotesque gaiety about the place. The brightly painted building sits on a sunny hillside directly across from Tijuana's modern seaside bull ring. On a whitewashed wall outside there is a 10-foot mural showing a muscular man locked in battle with a giant crab - the cancer symbol.

But the people who arrive here are clearly not tourists. Most are hollow-cheeked or wear heavy makeup to hide the signs of cancer's ravages. New arrivals are handed a set of instructions by the clinic's "public relations man." The first is to visit the cashier's window.

The patients sit in a sunny room waiting for the scratchy public address system to call them for a consultation with one of the clinic's 14 doctors. The doctors administer Laetrile at $20 an injection or sell it in anything from single doses to several months' supply. A notice on the wall of the waiting room advises that it is legal to import Laetrile into Canada, but says nothing about the United States.

Laetrile seekers here talk openly among themselves about smuggling the drug back to the United States, occasionally wishing each other luck in getting past Customs.

"Oh my, yes," said Ida Beebe, a 74-year-old woman who was told not long ago by her doctor that her cancer is terminal. "We compare notes. There is, after all, a sort of common bond among us you know."

"If it works I want to try it," said a 33-year-old Dallas woman standing with her father under the crab mural. The woman said she had lymph node cancer diagnosed as incurable. "I don't want to find out when I'm in heaven or hell that it worked for someone else," she said.

The director of the clinic, Dr. Ernesto Contreres Rodriguez, acknowledged that many of his patients were smuggling the drug back into the United States.

"We prescribe it," said Contreres, a large, pleasant man who is considered the "father of Laetrile" by many here. "What the patient does with it is his own business, including taking it across the border."

Contreres, 61, runs the clinic and Del Mar Hospital as well as a motel here, where patients pay $600 or more for three-week sessions of cancer treatment. Contreres said the hospital also administered radiation and chemotherapy treatments for cancer in addition to Laetrile. "We are as good as any other oncology center," he said. "But here the patients receive what is best for them."

The border crossing between Tijuana and San Ysidro - the route home for most of Contreres' patients - is the busiest customs area in the United States, according to Customs officials. Twenty thousand cars and trucks pass through daily, but officials said they usually can spot those who have been to the Laetrile clinic.

"You can tell when a person is dying of cancer," said the station's acting chief inspector, John Young. He recalled that one man came through crying and carrying an emaciated little girl in his arms.

"We knew right away he was taking his daughter home from the clinic, but he said he didn't have any Laetrile with him," Young said. "If I decided he was smuggling. I guess I'd have to search him. But you use your own discretion sometimes."

Another official at the inspection station said he look his mother to the Del Mar clinic four years ago and she had a remission of her cancer. "I don't know whether it was from Laetrile," the inspector said. "But I do know that it makes it very hard for me to take the stuff away from these people."

Young and other officials at the border carefully checked the other day when Elbert Howell and his son, Lawrence, passed through on their way home to Oklahoma with several thousand dollars worth of the drug for the elder Howell's lung cancer. The Howells have obtained a court order allowing them to bring back the drug.

"But if I didn't get the order," said Elbert Howell, "I'm sure I would have gotten the stuff anyway and smuggled it back the same way everybody else does."

Customs officials acknowledge it is difficult stopping a cancer patient and seizing medicine he just paid several thousand dollars for, even if the scientific value of the medicine is unproven.

"We handle these people very carefully," said Young. Many Laetrile carriers don't know the drug is banned and admit to customs officials that they are carrying it, he said.

"Our job is to enforce the law, and the law says they can't bring Laetrile in," said Young. "We take it away, but we try to treat these people with all the dignity they deserve. After all, it's not like we were dealing with heroin smugglers."