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Big, Fat Tumors: Liposarcomas Can Top 70 Pounds

Medically Reviewed by Arefa Cassoobhoy, MD, MPH on October 05, 2018
From the WebMD Archives

Oct. 5, 2018 -- Two years ago, Hector Hernandez noticed his weight creeping up and his stomach popping out, but he chalked it up to middle age. His stomach had never really behaved, he admits.

But as it grew, people noticed. “I would get from people, 'You should stop drinking beer,' ” says Hernandez, 47, a billing administrator for an IT company in the Los Angeles area. He'd laugh it off and tell them he didn't even drink beer.

Yet he was becoming concerned. His weight had reached 298 pounds on his 5' 10" frame. "I would exercise and my stomach would never come down," he says. It felt hard, too, although that was nothing new either. When he noticed his arms getting thinner, and his family nudged him, he saw a doctor.

“The doctor touched my stomach and asked, ‘How long have you been like this?’ ” Then he sent Hernandez off for a round of tests, including images of his abdomen.

Soon came the shocking diagnosis: He had a cancer of the fat cells growing in the back of his abdomen. The tongue-twisting medical term is retroperitoneal liposarcoma.

On July 10, William Tseng, MD, a cancer surgeon at the University of Southern California Keck School of Medicine, Los Angeles, removed the tumor. When the painstaking 6-hour operation, was finished, Hernandez was 77 pounds lighter -- that’s how massive his tumor was.

Tseng says it was the largest he’s ever removed, and he is a sarcoma specialist. Typically, they are about 20 to 30 pounds, he says.

Despite the tumor's heft, Hernandez says he never felt any pain, even as the mass gradually took up more and more space in his body.

About Liposarcomas

The location of these abdominal tumors helps explain how they can become so big without the person realizing it, Tseng says. “Most patients never suspect they have this,” he says.  “Typically, they grow in the back of the abdomen. They start out small.” But they can expand to the size of a watermelon.

The symptoms, if any, are vague. Some patients may say they don't have as many bowel movements as before, or they feel bloated. They tend to blame an unhealthy diet or their menstrual cycle, among other things. Some notice thinning arms, as the tumor saps their nutrition.

Or, like Hernandez, they may become aware that their stomach is becoming hard. That was what Donald Jimenez, 56, an executive chef in Los Angeles, noticed.

“When I ate, it got really hard,” he says. He was diagnosed with the same cancer earlier this year. His tumor weighed 28 pounds.

These tumors get discovered almost accidentally, Tseng says. A patient may see a doctor for another complaint and the tumor shows up on a CT scan. In some cases, Tseng says, a needle biopsy is needed to make the diagnosis, but when a large tumor shows up on a CT scan, that is enough proof to diagnose it, he says.

Rare, Mysterious Tumor

Sarcomas in the soft tissues (such as fat, nerves, ligaments, muscles) of all types are rare, accounting for less than 1% of all malignant tumors in adults. In 2018, the American Cancer Society estimates, about 13,000 new soft-tissue sarcomas of all types will be diagnosed, and about 5,000 Americans will die of them.

Among these types, the most common soft-tissue sarcoma is liposarcoma, Tseng says. Liposarcomas also happen in the limbs, but they’re typically found much earlier before they grow to the size of the tumors that take up residence in the abdominal area.

Patients are usually in their mid-50s when the cancer is found. Although liposarcoma was first described in 1761,experts still have many unanswered questions.  

When patients first hear the diagnosis, they often ask what they did wrong, says Nita Ahuja, MD, chairwoman of the department of surgery at Yale University School of Medicine and surgeon-in-chief at Yale New Haven Hospital. And the answer is usually, “Nothing.”

“If you take 95% of my patients, there are no known risk factors,” she says. Nor does the cancer have anything to do with being overweight. Ahuja tells her patients: “Liposarcoma is from the fat cell; it doesn't mean you are fat.”

Most of these abdominal sarcomas have no clearly identified cause, experts say, although genetic changes and exposure to radiation and chemicals can raise the risk of getting one.

Christina Roland, MD, assistant professor of surgery and sarcoma section chief at MD Anderson Cancer Center in Houston, gets the same questions from her patients. “People want to know what they have done so they can fix it. There is nothing to fix,” she tells them.

The 5-year survival for retroperitoneal sarcomas is about 40% to 60%, the American Cancer Society estimates, but it depends on many things, such as the stage at which the cancer was diagnosed. Sarcomas of the arms and legs, if found early, have a 90% 5-year observed survival rate.

From 'Gentle Beast' to Not

The basics of these tumors are well-known. “It starts from a normal fat cell,” Tseng says.

Then, as all cancer cells do, it begins growing abnormally. In some cases, the cells change so much that, Tseng says, it transforms the cancer from a “gentle beast” tumor to a very aggressive one. When this happens, the tumor not only grows, but it can push aside organs, such as the kidneys and the liver, and can send tentacles into these organs or wrap around them.

That's what makes the operations so complicated and lengthy. A surgeon may have to decide, “Do I have to take the kidney, or part of the liver or colon, to remove as much of the cancer as possible?” The surgeon is always trying to achieve a delicate balance – keeping quality of life while removing as much of the cancer as possible.

In the case of Jimenez, the chef, Tseng had to remove the right kidney, as the tumor had wrapped itself around it, but he was able to preserve the colon. Jimenez is happy to be rid of the mass.  

"You take the news as you can," he says. Just 2 months after his surgery in May, he was back at work.

Surgery is the only treatment needed for many, but others may need chemo or radiation.

The Beast Will Be Back

Even after the most successful of surgeries, doctors often have some bad news. The tumor will probably be back. Overall, within 5 years, about half return, Tseng finds.

And the larger the tumor, and the more advanced the cancer when detected, the higher the chance of it returning.  

"When the tumor is very large, I tell them the recurrence risk is probably almost 100%," says Roland, of MD Anderson Cancer Center.

Why are these cancers so stubborn? Because they like organs, Tseng says. With other cancers, a surgeon can cut out the cancer and a portion of the tissue around it, producing what doctors call a “clean” or “clear” margin. But with the fat tumors in the abdomen, as the surgeon tries to preserve other organs, microscopic residual cancer cells can be left behind, Tseng says.

Better Treatment Needed

“The surgery we do is not adequate," Tseng says. “We are trying to find something better to wipe out the microscopic residual cells.” Those cells can cause trouble later.

One possibility is through immunotherapy. This uses substances made by the body or in a lab to prime the body's natural immune system to prevent or treat disease.

Roland is studying whether pre-op immunotherapy, with two cancer drugs already approved to treat other forms of cancer, might help prevent or reduce recurrences. The idea is that if the drug is given before surgery, the body is primed to fight off any cancer cells in the future. She is enrolling 40 patients with sarcoma tumors, including liposarcoma. She will study whether the drugs nivolumab (Opdivo) and ipilimumab (Yervoy), sometimes given in combination with radiation therapy, will cut down recurrences.

Another drug already used to treat breast cancer, palbociclib (Ibrance), may help stop some liposarcomas from spreading, says Mark Dickson, MD,  clinical director of the Sarcoma Medical Oncology Service at Memorial Sloan Kettering Cancer Center, New York City.  It may work, he says, because the gene known as CDK4 is overactive in many liposarcomas. The medication targets the CDK4 enzyme important for cell division, halting the division of cancer cells while not affecting normal cells as much.

In one study of 60 patients with advanced liposarcomas, Dickson found that the drug lengthened the time patients went without the disease spreading. But he says the CDK4 inhibitors may only stabilize the disease. “In practice, it is rarely a tumor-shrinking strategy,” he says.

The study was funded by the drug's maker, Pfizer, and Dickson has been a consultant for the company.

Importance of Monitoring

Until better treatments are here,  patients must prepare for long-term monitoring. Tseng suggests they think of this as a chronic disease, since it’s so likely to come back. Patients usually return every 4 months or so for the first 2 or 3 years for CT scans. At 5 years, they may transition to yearly scans, he says, but follow-up is different for every individual.

“If it is going to come back, it usually happens in 2 or 3 years,” Tseng says.

Life After Tumors

Even with the need for close follow-up, Hernandez sees reason to celebrate.

“My energy level is through the roof,” he says. “I don’t have diabetes anymore, and I don't have high blood pressure.” He took only 3 weeks off from work, then began working from home, with plans to return to the office soon.

At just 27, Heather McKelvey doesn't fit the profile for this kind of tumor. Yet the medical assistant in Huntington Beach, CA, had two surgeries to have several tumors removed, as well as part of her liver and colon and her right kidney.

She recalls her first suspicions. While lying down, she had rested her hand on her stomach and suddenly felt a bump. “It may have been the size of a quarter or a dime,” she says. “A month later, it was still there.”

She worries that it could happen again but has not slowed down. With only one kidney, she is conscientious about her diet, and she drinks enough water. Just weeks out of her second surgery, she is limited to walking for exercise. But not for long, she vows.

"I'm going to try to do a triathlon in April with my brother," she says.

Show Sources

William Tseng, MD, associate professor of surgery, Keck School of Medicine of USC, Los Angeles.

Hector Hernandez, billing administrator in information technology, Downey, CA.

Donald Jimenez, executive chef, Los Angeles.

Heather McKelvey, medical assistant, Huntington Beach, CA.

Christina Roland, MD, assistant professor of surgery and sarcoma section chief, MD Anderson Cancer Center, Houston.

Nita Ahuja, MD, chairwoman, department of surgery, William H. Carmalt Professor of Surgery, Yale University School of Medicine; surgeon-in-chief, Yale New Haven Hospital, New Haven, CT.

Mark Dickson, MD, clinical director, Sarcoma Medical Oncology Service, Memorial Sloan Kettering Cancer Center, New York.

F1000 Research:  "Recent advances in the management of liposarcoma."

JAMA Oncology: "Phase 2 Trial of the CDK4 inhibitor Palbociclib (PD0332991) at 126 mg dose in Well-Differentiated or Dedifferentiated Liposarcoma."

Journal of Surgical Oncology: "Long-Term Outcomes in Treatment of Retroperitoneal Sarcomas: A 15 Year Single-Institution Evaluation of Prognostic Features."

Frontiers in Surgery: "Retroperitoneal Liposarcoma: Current Insights in Diagnosis and Treatment."

American Cancer Society: Key Statistics for Soft Tissue Sarcomas. April 6, 2018.

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