Each time it happened, Johanna Dickson thought it was something she had eaten.

The first attack struck while Dickson, then 23 and just back from a vacation in South Africa, was attending a party in New York. She assumed that the piercing abdominal pains might be a legacy of her trip or, more likely, the consequence of bad sushi she had consumed before the party.

As the pain worsened, Dickson remembers wondering, “Is this what childbirth is like?” The next morning she saw her family doctor in New Jersey, who sent her to the hospital for tests. Soon afterward, the symptoms disappeared, and when testing revealed nothing, Dickson said she “moved on.”

Six months later, she experienced a second episode, followed by another a year later. The third attack would end far differently than the first two: Doctors at a New Jersey hospital decided that, based on the results of her CT scan, Dickson needed emergency surgery.

[Doctors dismissed his pain as migraines. Then they said he had 24 hours to live.]

Johanna Dickson thought her excruciating stomach pains were caused by food poisoning at first. It soon became clear the issue was more serious, but Dickson's eventual diagnosis shocked both her and her doctors. (Deirdra O'Regan/The Washington Post)

“Something like this is very strange in a 24-year-old,” said Kenneth A. Goldman, the surgeon who operated on Dickson in August 2008. Goldman said he approached her case with some trepidation, “hoping for the best and assuming the worst.”

For Dickson, who now works as a book publicist in Manhattan, the first episode was a surprise. She had felt fine on vacation and been generally healthy during the previous year she had spent in South Africa on a college study program. Because she had worked with orphans who had HIV, Dickson underwent testing for infectious diseases after she returned to the United States from her year abroad. “I assumed if there was anything serious, I’d find out about it,” she recalled.

The second attack, which caused stabbing pain so intense it woke her from sleep, passed fairly quickly; this time, she didn’t go to the doctor.

But the pain during the third episode was much worse. Dickson, who was then living with her parents near Princeton, said that it began in the middle of the night and grew so unbearable that she began screaming. Her mother held her and tried to soothe her; in the morning, her parents rushed her to the doctor’s office.

He decided that Dickson probably had food poisoning — she had bought fruit from a street vendor the previous day. Although her pain, which was mostly on her left side, seemed somewhat lessened, the doctor told Dickson’s parents that if it didn’t subside by noon, she should go to the hospital for an abdominal CT scan. One possibility was acute appendicitis, although that typically causes pain on the right side.

[He couldn’t eat, drink or work. And doctors couldn’t explain his searing pain.]

Dickson was little better by noon, and her parents took her to the hospital. Several hours later, an ER doctor entered the room and asked a series of rapid-fire questions. “He wanted to know if I’d ever given birth, or had surgery or had a family history of colon problems,” Dickson recalled.

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The answer to each question was no.

“Why?” Dickson remembers her father inquiring.

The doctor explained that the CT scan showed that Dickson’s pain was the result of a serious bowel obstruction. The most likely cause at her age was scar tissue from previous surgery. Another possibility was an inflammation of her colon. Because Dickson had never had any surgery — she had never been in a hospital — and no history of colon problems, doctors had no idea what was causing the obstruction. A surgeon was on his way to see her and would decide whether she needed an operation or whether the problem might resolve without it.

[A simple test proved that a teen with stomach pain wasn’t a hypochondriac after all]

A bowel obstruction occurs when the large or small intestine is partially or totally blocked, preventing food, fluids and gas from passing normally. It typically causes severe pain that may wax and wane.

Through a morphine haze, Dickson remembers feeling terrified about the prospect of surgery. Goldman told Dickson and her parents that surgery was essential. “I remember hearing something about my intestine being really badly tangled and that it was something you [usually] see in people over 60.”

The primary concern was that the obstruction was cutting off the blood supply to Dickson’s colon; an operation to untwist the intestine and relieve the obstruction was the only treatment. Causes of a blockage include a hernia; Crohn’s disease, a disorder that causes inflammation of the gastrointestinal tract; previous abdominal surgery, including a Caesarean section, which results in the formation of scar tissue; and a tumor.

Goldman remembers wondering what he would find. “I’ve seen 25-year-olds with metastatic colon cancer,” he said.

Shortly before 7 p.m., Dickson was wheeled into surgery.

A surprising discovery

In the operating room, Goldman discovered the source of the obstruction: a tumor the size of a plum in Dickson’s small intestine. He sent samples of the tumor — called frozen sections — to the pa­thol­ogy lab and waited for the initial report.

[She couldn’t stop coughing. Were fragrances to blame?]

The pathologist found that the specimen contained abnormally shaped spindle cells — round in the middle with pointed ends. Because such a finding is rare and its implications unclear, Dickson’s pa­thol­ogy samples were subsequently sent to the Mayo Clinic in Rochester, Minn., for a second opinion. In the meantime, Goldman decided that in case Dickson did have an invasive cancer, he needed to remove enough of her intestine — about 10 inches — to ensure that no malignancy remained. Dickson said she suffered no ill effects from the surgery.

The next morning, Dickson recalled, Goldman explained that the first two episodes had probably been caused by the bowel partially twisting around the tumor and then untwisting. Once the tumor grew too large, surgery was essential.

The Mayo pathologists classified the tumor as an extremely fibrous growth called a desmoid, a slow-growing mass that typically affects women younger than 40.

Because the tumor was attached to the mesentery, the fold of tissue that connects the small intestine to the abdominal wall, the condition is also called mesenteric fibromatosis. About 900 desmoid tumors are diagnosed annually in the United States.

There is disagreement about whether such tumors should be classified as benign — largely because they do not spread — or as a low-grade form of cancer. Dickson said she was told her tumor was benign.

Surgery to remove desmoid tumors is the preferred treatment, but recurrence is common. Many desmoid tumors, which can develop anywhere in the body, have no known cause. Some occur in people with Gardner syndrome, a type of familial adenomatous polyposis, a genetic disorder that results in frequent colon polyps in adolescence and in early-onset colon cancer.

[Why I hid my daughter’s medical diagnosis from her for as long as I could]

No recurrence

But in Dickson’s case, no genetic link could be found.

Dickson said she underwent frequent monitoring the year after her surgery as well as a colonoscopy, which found nothing. She sees an oncologist periodically for follow-up, but so far the tumor has not recurred.

In 2013, five years after the surgery, Dickson underwent a second abdominal operation, which involved removal of more of her intestine, to relieve pain caused by scar tissue from the 2008 operation.

“I thought, ‘Oh, my God, am I going to be doing this every five years?’ ” she remembered wondering. There is no way to prevent a recurrence — doctors don’t know what caused the tumor — but Dickson said she is careful about her diet, avoiding fried foods and dried fruit, which she has trouble digesting.

These days stomachaches always get her attention.

“If Pepto [Bismol] doesn’t work after about 20 minutes,” she said, “I do get a little nervous.”

To Goldman, Dickson remains a singular event in his long surgical career. “I’ve seen one case of this in my 32 years,” he said. “That was Johanna.”