What is Renal Medullary Carcinoma?
Renal Medullary Carcinoma (RMC) is an extremely rare form of kidney cancer that most commonly affects young adults with blood sickling abnormalities, specifically Sickle Cell Trait. RMC is one of the most agressive renal cell carcinomas and often patients do not present with symtoms until late in the disease progression. There are different treatment options depending on whether the tumor is in one place or spread to other parts of the body. Common treatments may include surgery or systematic drug therapy (chemotherapy).
Common symptoms include blood in the urine (hematuria), pain in the flank around the kidney area, weight loss, and night sweats/elevated body temperature.
What To Do if You or a Loved One is Diagnosed with RMC:
Find a partner. For many people, this will be a spouse, family member, or close friend. Pick someone you can talk to openly about treatment and next steps.
Get organized. Start a notebook or a binder to coordinate appointments, keep track of your doctor's contact information, and to write down any questions you may have for your healthcare team. Take it with you to each medical appointment, and keep notes on your test results and treatment options. Ask questions!
Join a support group. The Chris 'CJ' Johnson foundation currently holds monthly RMC support group meetings through the website ANCAN. Link to Join
Find a provider in your area and create a treatment plan that works best for you! Provider Link to the MD Anderson Cancer Center team who specialize in RMC treatment.
Stages of Disease
Understanding the stage of your cancer and the potential treatment options can help you have more informed discussions with your healthcare team and increase your confidence that you are making the right decision about your health and treatment:
Stage 1: The tumor is 7 cm across or smaller and is only in the kidney. There is no spread to the lymph nodes or distant organs.
Stage 2: The tumor is growing into a major vein (like the renal vein or the vena cava) or into the tissue around the kidney, but it is not growing into the adrenal gland or beyond Gerota’s fascia. There is no spread to lymph nodes or distant organs.
Stage 3: The main tumor can be any size and may be outside the kidney, but it has not spread beyond Gerota’s fascia. The cancer has spread to nearby lymph nodes but has not spread to distant lymph nodes or other organs.
Stage 4: The main tumor can be any size and may have grown outside the kidney. It may or may not have spread to nearby lymph nodes. It has spread to distant lymph nodes and/or other organs.
Who is Most at Risk For Developing RMC?
A risk factor is anything that increases the chance of developing a particular disease. The risk factors for RMC include:
Sickle hemoglobinopathies: People with sickle hemoglobinopathies have increased risk for RMC. The most common sickle hemoglobinopathy is the sickle cell trait. Other sickle hemoglobinopathies that increase the risk for RMC include sickle cell disease (also known as sickle cell anemia), hemoglobin SC disease, or sickle beta thalassemia.
Race/ethnicity: In the U.S., Black people are more likely to develop RMC because the sickle cell trait is most common in this group. The sickle cell trait is also common in people from certain regions of Greece, southern Turkey, central India, eastern Brazil, the Dominican Republic, eastern Saudi Arabia and equatorial Africa.
Very intense exercise: Doctors believe that very intense exercise can trigger RMC, especially in people with the sickle cell trait. However, moderate exercise may actually prevent RMC while producing many other health benefits.
Age: Most cases of RMC are in people under age 30.
Gender: Men are twice as likely to develop RMC than women.
What Causes RMC?
The exact reason why RMC develops is not fully understood. A large number of RMC patients will have a blood disorder that can make their red blood cells sickle. Other than the presence of sickle hemoglobinopathy, there are no other known family predispositions or risk factors in the environment that can explain why only certain individuals will develop RMC. There is currently no evidence to suggest that family members of a patient with RMC are at increased risk for developing RMC themselves. Although individuals with sickle hemoglobinopathies should take early signs and symptoms of possible RMC very seriously, there are currently no known effective strategies to prevent or screen for RMC in individuals without symptoms.
Notably, all RMC tumors lack a protein called INI1, also known as SMARCB1, hSNF5, or BAF47. This protein is also often lost in other rare cancers such as malignant rhabdoid tumors (MRT), atypical teratoid rhabdoid tumors (ATRT), and epithelioid sarcomas. INI1 is a “tumor suppressor” that normally protects cells from turning into cancer.
The red blood cells of individuals with sickle cell disease have changed into a sickle shape throughout the body and this can produce multiple health problems and symptoms unrelated to RMC. It is thought this sickling process can sometimes damage the INI1 gene in cells within the renal medulla thus resulting in RMC. In rare cases, INI1 may be lost in the cells of the renal medulla in individuals without any sickle hemoglobinopathies, thus resulting in a subtype of RMC provisionally called “renal cell carcinoma, unclassified with medullary phenotype” (RCCU-MP).