Intestinal Transplant for PMP: Why Late Referral Closes the Door

An intestinal transplant for PMP is an option for a small number of carefully selected people whose pseudomyxoma peritonei can no longer be removed with conventional surgery and whose disease has caused severe intestinal or nutritional failure. A 2025 conference report from the Oxford Transplant Centre found that most people referred for it arrive too late to be listed.

I went through a two page conference abstract from the Oxford Transplant Centre and the Peritoneal Malignancy Institute in Basingstoke. It covers a treatment that almost never comes up in appendix cancer conversations, and it says something uncomfortable about timing. An intestinal transplant for PMP may offer another treatment option for a few people who have run out of conventional surgical options. Most of the people who got sent to Oxford were sent too late for it to be possible.

What an intestinal transplant for PMP actually is

Pseudomyxoma peritonei fills the abdomen with mucin. For many people with resectable PMP, cytoreductive surgery, often with HIPEC, is the standard surgical approach, sometimes more than once. But in some people the disease coats the small bowel so completely that a surgeon cannot leave behind enough working intestine. The bowel obstructs. Nutrition fails. Some people develop fistulas through the abdominal wall.

For a very small number of carefully selected patients who have no conventional surgical option left, intestinal or multivisceral transplantation may offer another approach. Surgeons remove the affected abdominal organs and replace them with a donated small bowel, or with a modified multivisceral graft that includes more than the intestine. In the Oxford series, seven of fifteen people also received a full thickness abdominal wall transplant, because the tumor had destroyed the wall itself.

This operation exists at a handful of centers in the world.

Ten years of referrals, and what happened to them

The Oxford team looked at every PMP patient referred to them between January 2015 and December 2024. Forty nine assessments were done.

Seventeen people, or 35 percent, went on to a transplant. Eleven people, about 22 percent, were listed but never transplanted. Most of those either deteriorated while waiting or ended up having debulking surgery instead. The remaining twenty one people, 43 percent of everyone assessed, were never listed at all. They were not suitable.

So more than four out of ten people who made it as far as a transplant assessment had already passed the point where the operation was possible.

BMI did not separate the groups. Muscle measurements did.

This is the part I think matters most for people reading this at home.

The Oxford team measured body composition on CT scans taken before transplant. They calculated skeletal muscle area at the L3 vertebra and adjusted it for height to get a skeletal muscle index. They also recorded BMI, grip strength, and mid arm muscle circumference.

BMI was nearly the same in every single group. The people who were transplanted and did well had a mean BMI of 22.2. The people who were never listed had a mean BMI of 21.4. Those two numbers both sit in the middle of the normal range. If you were looking only at BMI, you would not be able to tell those two groups apart.

The skeletal muscle numbers were spread much further apart. The group that was transplanted and did well averaged 35.09. The group that was never listed averaged 26.69. Grip strength followed a similar pattern. The never listed group sat between the third and tenth centile, which is very low. The abstract reports these as descriptive comparisons across four small groups, so they show a pattern rather than a validated way to predict who will do well.

The reason BMI struggles here is straightforward. Tumor and mucin have weight. A body full of mucinous disease can put a perfectly ordinary number on the scale while the muscle underneath is disappearing. The authors said it plainly: BMI cannot be relied upon in this population.

If your team is telling you your weight is fine, that is not the same as telling you your nutrition is fine. A CT scan you have already had may be used to measure skeletal muscle, and grip strength can provide another quick measure of physical reserve. Neither one settles the question on its own, but both give information the scale does not.

The criteria that decide who is still eligible

A phase 2 study registered in the United States lists who this operation is meant for, and those criteria show how narrow the window is.

Disease has to be unresectable. The study defines that as at least one of the following: the surgeon cannot preserve at least one and a half to two meters of small bowel, the pancreatic surface is extensively infiltrated, the mesentery is retracted, the whole stomach would have to come out, a ureter is obstructed, liver disease cannot be cleared with enough liver left over, or recurrent disease cannot be resected again.

Then there are the criteria about the person rather than the tumor. Age eighteen to seventy five. ECOG performance status of zero or one, which means you are still up and about most of the day. No extra abdominal spread except in the lungs. No other curative option available.

That performance status requirement is why early referral matters. By the time someone is spending most of the day in bed, they no longer qualify, even though that is exactly when the disease feels most urgent. The Oxford authors made the same point. Earlier referral gives time for nutritional prehabilitation and for an honest conversation about a high risk operation, and it means the assessment happens while the answer can still be yes.

Where this is done, and what is registered in the United States

The Oxford program published its full results in Annals of Surgery in 2023. Fifteen patients were transplanted between 2013 and 2022. Eight had an isolated small bowel transplant and seven had a modified multivisceral transplant. The paper is free to read on PubMed Central, and the authors report that most patients had a significant improvement in quality of life afterward.

For people in the United States, there is now a registered study. TRANSCAPE, NCT06084780, is a phase 2 prospective case series at the Cleveland Clinic Digestive Disease and Surgery Institute, run through Case Comprehensive Cancer Center, with Dr. Masato Fujiki listed as the site contact. It plans to enroll twenty people. The registry entry states the goal as assessing the efficacy and safety of intestinal or multivisceral transplantation in people with PMP not amenable to other curative intent treatments, and describes the study as an effort to corroborate the Oxford results in an American cohort. As of the current ClinicalTrials.gov record the status is not yet recruiting, so this is something to ask about and track rather than something you can enroll in today.

Both low grade and high grade mucinous carcinoma peritonei are eligible in that study, with or without signet ring cells, and previous CRS with HIPEC does not disqualify you.

What this does not cover

The Oxford referral review was reported as a conference abstract in Intestinal Failure in 2025 rather than as a full research paper. The numbers in it come from forty nine people at one center, and the transplanted group is seventeen people. That is a small series, and the four groups being compared are smaller still.

The work covers pseudomyxoma peritonei and mucinous carcinoma peritonei. It does not cover goblet cell adenocarcinoma, non mucinous appendiceal adenocarcinoma, or appendiceal neuroendocrine tumors. Do not carry these findings over to those subtypes.

An intestinal transplant for PMP carries serious risks, and the published Oxford paper says so. Two of the fifteen transplanted patients died within ninety days from complications related to the surgery. Disease was found again in 91 percent of the patients followed for more than six months. The goal of the operation is to extend survival and improve quality of life when conventional surgical options have been exhausted. It is not considered a cure, and nobody involved describes it as one.

Frequently asked questions

What is an intestinal transplant for PMP?

It is an operation in which surgeons remove the abdominal organs affected by pseudomyxoma peritonei and replace the small bowel with a donated one, sometimes along with other organs and part of the abdominal wall. It is considered for a small number of carefully selected people when the disease can no longer be removed by conventional cytoreductive surgery and there is severe intestinal or nutritional failure.

Who qualifies for an intestinal transplant for PMP?

Broadly, adults aged eighteen to seventy five with unresectable PMP, no curative alternative, no spread outside the abdomen apart from the lungs, and a performance status where they are still up and about most of the day. The exact criteria vary by center.

Is this available in the United States?

A phase 2 study called TRANSCAPE, NCT06084780, is registered at Cleveland Clinic through Case Comprehensive Cancer Center. As of the current ClinicalTrials.gov record it is listed as not yet recruiting. The established program with published medium term results is at the Oxford Transplant Centre in the United Kingdom.

My BMI is normal. Does that mean my nutrition is fine?

Not necessarily. In the Oxford referral group, BMI was almost identical whether someone was transplanted successfully or turned down entirely. Mucinous disease adds weight, which can hide muscle loss. Skeletal muscle measured on a CT scan and a grip strength test can provide additional information about muscle and nutritional status.

Is an intestinal transplant a cure for PMP?

No. In the published Oxford series, disease was detected again in 91 percent of patients followed longer than six months. It is offered to extend survival and improve quality of life when conventional surgical options are gone.

Sources. Yates C, Woodhouse E, Camp F, Corbey K, Vokes L, Mohamed F, Dayal S, Moran B, Udupa V, Reddy S, Allan P, FitzPatrick M, Cecil T, Ambrose T, Canovai E. Intestinal Transplantation for End-Stage Pseudomyxoma Peritonei (PMP): The challenge of Early Referral in Optimising Outcomes. Intestinal Failure 2025;6:100151. doi.org/10.1016/j.intf.2025.100151. Reddy S, Punjala SR, Allan P, et al. First Report With Medium-term Follow-up of Intestinal Transplantation for Advanced and Recurrent Nonresectable Pseudomyxoma Peritonei. Annals of Surgery 2023;277(5):835-840. Free full text on PubMed Central. TRANSCAPE, NCT06084780, ClinicalTrials.gov.

Appendicure is a 501(c)(3) nonprofit, EIN 41-5040966. If this was useful, you can support the work here.