An angiomyolipoma refers to a benign tumor in the kidney that is characterized by a particularly high proportion of fatty tissue. Angiomyolipomas occur exceedingly rarely and in the majority of cases affect women in the age range between 40 and 60 years. In approximately 80 percent of cases, angiomyolipoma in the kidneys is asymptomatic, causing no symptoms.
What is angiomyolipoma?
Angiomyolipoma, as a benign tumor with high fat content, originates from special cells in the kidney called epithelioid cells. The tumor is thought to grow in a hormone-dependent manner. Angiomyolipomas have a round to oval shape and bulge over the kidney capsule. Sometimes they grow in multiple sites, and the lymph nodes may also be involved. However, there is no risk that angiomyolipomas will begin to metastasize. Histological studies of angiomyolipomas show that these tumors of the kidney are characterized in particular by mature fat cells as well as smooth muscle cells and blood vessels. The asymptomatic angiomyolipomas, which can occur in either kidney and do not result in symptoms, are found with approximately equal frequency in women and men. In this patient population, a peak age is found at approximately 30 years. In some cases of asymptomatic angiomyolipoma, association of the renal tumors with tuberous sclerosis (medical name Bourneville-Pringle disease) occurs.
Causes
With regard to the disease angiomyolipoma, which can affect the kidneys, various known causes exist. In most cases, angiomyolipoma originates from perivascular epithelioid cells. These cells are special cells of the connective tissue that are located around a vessel. The growth and control of these perivascular epitheloid cells are dependent on certain hormones, according to current evidence. Although angiomyolipomas do not metastasize, in some cases the tumors may grow into the surrounding fatty tissue of the kidney, the renal pelvis, or sometimes into the renal veins. This can result in various complications. The presence of angiomyolipomas accounts for about one percent of all surgical findings. In addition, angiomyolipoma is found to be associated with tuberous sclerosis disease in approximately 20 percent.
Symptoms, complaints, and signs
When angiomyolipoma is present, the affected patient may experience various symptoms. In most cases, it is an asymptomatic angiomyolipoma that does not cause any symptoms or complications. As a result, the disease is not noticed by the respective affected person, since no symptoms appear. Consequently, angiomyolipoma cannot be diagnosed and treated by a physician. This is relatively common, as angiomyolipoma is asymptomatic in about 80 percent of cases. In the remaining cases, various symptoms caused by angiomyolipoma may present in affected patients. In most cases, the symptoms are manifested by flank pain, which is an indication of the tumor in the kidney. In addition, potentially dangerous complications can also occur in the context of an angiomyolipoma. For example, life-threatening hemorrhage may occur, caused by spontaneous rupture in the retroperitoneum (medical term Wunderlich syndrome). If pregnancy is present, the risk of such rupture is increased.
Diagnosis and course
Various methods of examination are available to establish the diagnosis of angiomyolipoma, which are selected by the attending physician depending on the symptoms shown. For example, imaging techniques may be used to diagnose the disease. Ultrasound examinations may reveal pronounced echogenic space-occupying lesions in the kidney, which may be due to the high lipid content of the angiomyolipoma. On the other hand, analysis of blood vessels in the kidney is not a useful method for differential diagnosis because vascular neoplasms may occur in angiomyolipoma, similar to the presence of renal cell carcinoma. Computer tomography is also possible. This makes it possible to differentiate it from malignant renal cell carcinoma. In addition, calcifications do not occur in angiomyolipoma, which also contributes to a reliable differentiation.MRI can also image a particularly high fat content, which forms evidence of the presence of angiomyolipoma and does not indicate renal cell carcinoma.
Complications
Angiomyolipoma is a benign, adipose tissue tumor that attaches to the kidney. Women in midlife and older are most affected by this symptom. In some cases, angiomyolipoma is accompanied by tuberous sclerosis. Due to the diversity of symptoms that occur such as: Flank pain and cramps in the pelvic area, medical clarification is recommended. Once the diagnosis is made, resulting complications can be avoided. Particularly life-threatening is the rupture that occurs spontaneously in the retroperitoneum, also known as Wunderlich syndrome. Pregnant women in particular are at increased risk, as severe bleeding occurs behind the peritoneum. It is suspected that the tumor grows in a hormone-dependent manner and can spread to the kidney area. The angiomyolipoma cannot metastasize. Therapeutic measures are initiated according to the nature and size of the tumor. If the angiomyolipoma is larger than four centimeters, partial removal of the kidney must be targeted. Often, however, this is only a minimally invasive procedure. Recurrences can occur as a complication of selective embolization. By means of a drainage the necrotic tissue is drained. The diagnosis is differentiated from asymptomatic angiomyolipoma, which affects both kidneys but does not show any complication. It occurs in women and men around the age of 30. Asymptomatic angiomyolipoma is not noticed by the affected individual.
When should you see a doctor?
Recurrent flank pain, blood in the urine, fatigue, and other symptoms that indicate serious internal organ disease should be evaluated by a physician. The physician can use imaging techniques and a medical history to determine whether the tumor is an angiomyolipoma and, if necessary, initiate appropriate treatment. In any case, the benign tumor should be surgically removed. The earlier this is done, the less likely are serious complications. A visit to the doctor is recommended at the latest if the pain increases or if there is a sudden intense, throbbing pain in the flank region. The latter indicates a rupture behind the peritoneum (Wunderlich syndrome), which must be treated immediately. High-risk groups such as pregnant women and people with chronic kidney disease should see a doctor immediately if angiomyolipoma is suspected. Those already suffering from cancer should talk to the doctor in charge if they experience any unusual symptoms. In addition, if there are severe complications such as circulatory problems, severe pain, or rupture, emergency medical services should be called.
Treatment and therapy
Various options are available for the therapeutic treatment of an angiomyolipoma, which are selected according to the clinical picture and severity of the tumor. In the case that the angiomyolipoma has a size of more than four centimeters and is accompanied by pronounced symptoms, partial removal of the kidney must be considered. Another therapeutic option is the so-called selective embolization, which is a minimally invasive therapeutic method. However, with this form of treatment, recurrence is possible and drainage of the corresponding necrotic tissue may be required.
Outlook and prognosis
The prognosis of a cure prospect for angiomyolipoma depends on the time of discovery of the irregularity as well as its subsequent initiation of treatment. If found early, surgical intervention can be performed to completely remove the altered tissue immediately before further growth. There is a possibility that the patient will be free of symptoms afterwards and it will remain permanently. Likewise, further down the road, an angiomyolipoma may grow again. If the tumor grows into organic tissue, there is a risk of dysfunction as well as permanent impairment of organ function. Kidney function is impaired and numerous symptoms occur. Removal of the affected tissue can lead to lifelong kidney dysfunction. Depending on the existing damage, there is a need for organ transplantation to save the patient’s life as well as to preserve his quality of life.
Prevention
With regard to angiomyolipoma, according to current scientific knowledge, there are no known methods for prevention of the disease. It is of even greater relevance to have medical examinations performed at the first symptoms that may indicate angiomyolipoma. As a symptom, the focus is particularly on flank pain, which can generally indicate various diseases of the kidney and should always be medically clarified.
Follow-up
Cancer disease requires continuous follow-up care. This is because it cannot be ruled out that a tumor will form again. It is considered statistically proven that after five years, the probability of a relapse has decreased significantly. After a close-meshed examination network, only one or two appointments per year are then required. In most cases, an aftercare plan is already discussed as part of the initial therapy. Patients should discuss this with their treating physician in good time. If the kidney is damaged during initial treatment, blood washes are sometimes necessary. So far, there are no scientifically proven ways to stop the reoccurrence of an angiomyolipoma. However, the general rules for cancer patients are proving useful. Affected individuals should maintain a balanced diet after an initial attack. Addictive substances such as nicotine and alcohol should be avoided. A healthy life also includes daily exercise. Psychological pressure should be avoided and, if necessary, shorter working hours should be taken. During the follow-up examination, the attending physician will inquire extensively about the patient’s state of health. Even minor complaints can indicate a recurrence of the disease. In most cases, a blood test is performed. Imaging procedures such as a CT scan and MRI are also used.
Here’s what you can do yourself
Depending on its cause, an angiomyolipoma can be treated in different ways. Usually, drug therapy is given to relieve pain and regulate hormonal balance. The patient can support this by noting any side effects and interactions as well as the positive effects of the preparations used. Optimally adjusted medication improves the patient’s prospects of recovery and well-being. The actual symptoms can be treated by conservative measures. For example, cooling compresses and rest are helpful against flank pain. If bleeding is detected, the physician must first be informed. Accompanying this, avoiding strenuous physical activity can help reduce the pain. The patient should follow the doctor’s instructions regarding diet and physical activity during treatment. Stress and other psychological distress should be reduced whenever possible. If the course is severe, a therapist may be consulted. The physician in charge must answer what measures affected persons can take apart from this to reduce the symptoms.
