Renal Medullary Carcinoma - Causes and Treatment

What Is Renal Medullary Carcinoma?

If you are dealing with renal medullary carcinoma (RMC), you should know it is one of the rarest and most aggressive kidney cancers. About one in 100 kidney cancer patients has this specific type. This tough form of kidney cancer first showed up in medical reports back in 1995.

So what exactly is RMC? It is a cancerous tumor that starts growing in your renal medulla, which is the inner part of your kidney. About 70 % of the time, it shows up in your right kidney. Unfortunately, the outlook can be challenging. Fewer than five percent of people with RMC make it to the three-year mark after their diagnosis. That is why catching it early can help make your treatment more manageable.

What Are the Causes of Renal Medullary Carcinoma?

Doctors and scientists are still not entirely sure what triggers it. But it often starts when your red blood cells transform into a sickle shape in a specific part of your kidney called the renal medulla. When these cells change shape like that, they can block blood flow to that area.

This blockage can damage the INI1 gene in your renal medulla cells, leading to RMC. You might also hear INI1 referred to as the SMARCB1 gene; they are the same. SMARCB1 (SWI/SNF Related, Matrix Associated, Actin Dependent Regulator of Chromatin, Subfamily B, Member 1) is known as a tumor suppressor gene. Usually, it works hard to prevent the formation of cancerous tumors. But when a mutation occurs in this gene, it basically stops doing its job, and that is when tumors can start growing without anything to stop them.

If you have SCT (sickle cell trait), your red blood cells can block blood from reaching your renal medulla. Without a proper blood supply, the INI1 proteins in that area get damaged. And that damage might be what leads to RMC developing.

Risk Factors:

• If you have sickle cell trait or sickle cell anemia, you are at a higher risk of developing RMC, but having a family member with RMC does not increase your risk.

• You are more likely to see RMC in men than in women.

• It most often shows up when you are between 11 and 39 years old.

• In the United States, most people who get diagnosed with RMC (along with sickle cell conditions) are Black individuals.

What Are the Signs and Symptoms of Renal Medullary Carcinoma?

You might notice the following signs and symptoms if you are dealing with this condition:

• You could see blood in your urine (hematuria).

• You might feel pain around your kidneys.

• Sometimes you can feel a lump on your right side.

• You may start losing weight without trying.

• You could experience night sweats and run a fever.

How Is Renal Medullary Carcinoma Diagnosed?

If your doctor suspects you may have RMC, they will order imaging tests to get a closer look at your kidneys. These tests help them spot tumors and determine whether they are cancerous. You will likely get an MRI (magnetic resonance imaging) or a CT (computed tomography) scan; these provide your doctors with a clear picture of what is going on inside. Once they have reviewed those images, they can determine whether the mass appears suspicious.

Your doctor will need to do a biopsy to know for sure if it is cancer. They will use a thin needle to grab a tiny piece of tissue from the tumor. Then a pathologist will examine the tissue sample under a microscope to determine whether it is actually RMC.

For people who carry the sickle cell trait and start showing RMC symptoms, doctors usually start with an ultrasound. It is a quick way to get a good look at your kidneys without any radiation.

How Is Renal Medullary Carcinoma Treated?

If you are dealing with renal medullary carcinoma, the main treatments your doctor might recommend are as follows:

• Chemotherapy:

Chemotherapy for RMC involves medications that work to wipe out cancer cells and slow down their spread. This will help manage your symptoms. Your doctor might prescribe just one drug or combine several, depending on how your specific cancer behaves and how fast it is growing.

• Surgery:

When it comes to surgery for renal medullary carcinoma (called radical nephrectomy), your surgeon will usually need to remove your entire kidney. RMC tumors tend to be buried deep inside the kidney tissue, making partial removal challenging.

• Radiation Therapy:

This treatment uses radiation beams to destroy cancer cells in your body. Your doctor can deliver this therapy through different methods, depending on what works best for your situation.

• Proton Therapy:

It works similarly to regular radiation; proton therapy helps in curing tumors with incredible accuracy. You will have less radiation hitting your healthy tissues, which means your team can often use stronger doses where you need them most.

How to Prevent Renal Medullary Carcinoma?

We still do not know how to prevent RMC or how to tell if you have it when you are not showing any symptoms. If you have sickle cell hemoglobinopathy, keep an eye out for any warning signs of renal medullary carcinoma. It is not perfect, but right now, that is the most practical approach you can take.

What Is the Prognosis of Renal Medullary Carcinoma?

Years ago, if you were diagnosed with renal medullary carcinoma, doctors would tell you that you would likely have less than six months to live. But treatments have gotten better, and now more people are beating those odds.

Today, the median survival time after diagnosis is about 12 months. The median is the middle point, so about half of people with RMC live less than a year after finding out they have it, while the other half live past that one-year mark.

Conclusion

If you are dealing with renal medullary carcinoma, your chances of surviving longer really improve when doctors stay alert and catch it early. The sooner you get diagnosed and start treatment, the better your outlook becomes. RMC is rare, and it is an aggressive type of cancer that can affect you at any age. Most people only survive about four months after diagnosis because the cancer has usually already spread by the time it is found. That is what makes the prognosis so challenging. If you want to know more about RMC, you can ask a cancer specialist for further evaluation.

Key Takeaways

• Renal medullary carcinoma is a rare and aggressive form of kidney cancer that can affect your kidneys. Most commonly, it will affect your right kidney.

• You may have a fever, night sweats, blood in your urine, and pain in your kidney area.

• If the cancer has spread to other body parts, it can be life-threatening. You should immediately consult the doctor.