Adenocarcinoid Tumor: Causes, Symptoms, and Treatment
Medically reviewed by Harsha Moole, MD, Internal Medicine. Last reviewed: October 2, 2026.
What kind of doctor treats Adenocarcinoid Tumor?
An oncologist, a doctor who specializes in treating cancer, usually guides care, and a surgeon often removes the tumor. Because these tumors are rare, some patients are referred to a cancer center with experience in rare digestive tumors. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What it is
An adenocarcinoid tumor is a rare growth with features of two tumor types: adenocarcinoma, a cancer of gland cells, and carcinoid, a slow-growing tumor of hormone-making cells. Most are found in the appendix, a small pouch attached to the large intestine. Because they are rare, doctors are still learning the best ways to treat them.
Symptoms
Many adenocarcinoid tumors cause no symptoms and are found by accident during surgery or imaging tests. When symptoms happen, they depend on the tumor's location. A tumor in the appendix may cause lower right belly pain, sometimes like appendicitis, along with bloating, nausea, or changes in bowel habits. Rarely, these tumors release hormones that cause flushing or diarrhea.
Causes and who gets it
Doctors do not know exactly what causes these tumors, which start when cells in the digestive tract grow in an unusual way. They are most often diagnosed in adults and appear slightly more often in women. A family history of digestive cancers may raise the risk a little, but most cases happen with no family history.
How doctors diagnose it
Doctors often find these tumors during surgery or imaging such as a CT scan done for other reasons. If a tumor is suspected, a surgeon may remove the appendix or take a tissue sample, which a pathologist examines under a microscope to confirm the diagnosis. Extra scans may check whether it has spread.
Treatment
Surgery is the main treatment. Surgeons usually remove the appendix, and sometimes nearby tissue, depending on the tumor's size and spread. If it has spread, doctors may add chemotherapy. Afterward, patients need regular checkups and scans to watch for any return.
When to see a doctor
Anyone with lasting belly pain, unexplained weight loss, blood in the stool, or lasting bowel changes should see a doctor. These symptoms usually have other causes but always deserve a checkup. Sudden, severe belly pain needs attention right away.
How a direct primary care or concierge doctor fits in
A direct primary care or concierge doctor can be a steady partner during care, ordering imaging tests, checking symptoms, and managing follow-up visits. When a tumor is suspected, they will refer the patient to a surgeon and an oncologist. After treatment, they can handle routine checkups and coordinate reports from the cancer team.
Common questions
Is an adenocarcinoid tumor always cancer?
Some grow slowly and stay in one place, while others can spread. A pathologist studies the removed tissue to learn how the tumor is likely to behave.
How common are adenocarcinoid tumors?
They are very rare, making up only a small fraction of tumors in the appendix and digestive tract. Many general doctors may never see one.
Can adenocarcinoid tumors come back after treatment?
They can return in some cases, which is why regular follow-up visits and tests matter. The chance depends on the tumor's size, location, and whether it had spread.
Are there support groups for people with rare tumors?
Yes. Groups such as the Neuroendocrine Tumor Research Foundation and the National Organization for Rare Disorders offer information and connect patients. A care team can also help find support services.
Sources
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
