Clear-cell renal-cell carcinoma

File:Renal tumors by relative incidence and prognosis.svg

Renal tumors by relative incidence and prognosis

File:Histopathology of clear cell renal cell carcinoma, grade 1, intermediate magnification.jpg

Histopathology of clear cell renal cell carcinoma, grade 1, intermediate magnification

File:Histopathology of grade 3 clear cell renal cell carcinoma, annotated nucleolus.jpg

Histopathology of grade 3 clear cell renal cell carcinoma, annotated nucleolus

Clear-cell renal cell carcinoma (ccRCC) is the most common type of kidney cancer, accounting for approximately 70-80% of cases. This type of cancer is characterized by the presence of clear cells in the tumor, which are so named because of their appearance under a microscope. The clear cells are the result of accumulated lipids and carbohydrates, which push the cell's nucleus to the periphery. The exact cause of ccRCC is not fully understood, but several risk factors have been identified, including smoking, obesity, hypertension, and certain genetic conditions such as Von Hippel-Lindau disease.

Symptoms

The symptoms of clear-cell renal cell carcinoma may not be apparent in the early stages of the disease. As the tumor grows, symptoms may include blood in the urine (hematuria), flank pain, a mass in the abdomen, fatigue, weight loss, fever, and hypertension. However, many cases are asymptomatic and are discovered incidentally during imaging tests for unrelated conditions.

Diagnosis

Diagnosis of ccRCC typically involves a combination of imaging tests and biopsy. Imaging tests such as ultrasound, computed tomography (CT) scans, and magnetic resonance imaging (MRI) can help identify the presence of a kidney tumor and assess its size and spread. A biopsy, where a sample of the tumor tissue is removed and examined under a microscope, is performed to confirm the diagnosis of ccRCC.

Treatment

Treatment options for clear-cell renal cell carcinoma depend on the stage of the disease and may include surgery, targeted therapy, immunotherapy, and, less commonly, radiation therapy. Surgery to remove part or all of the affected kidney (nephrectomy) is often the first line of treatment. In cases where surgery is not possible, targeted therapies and immunotherapies that focus on inhibiting the growth and spread of cancer cells may be used.

Prognosis

The prognosis for patients with clear-cell renal cell carcinoma varies depending on the stage of the disease at diagnosis. Early detection and treatment significantly improve the likelihood of a favorable outcome. The five-year survival rate for patients with localized kidney cancer is high, but it decreases for those with cancer that has spread to other parts of the body.

Epidemiology

Clear-cell renal cell carcinoma is the most common type of kidney cancer in adults and is more prevalent in men than in women. The incidence of ccRCC has been increasing in recent decades, which may be partly due to the widespread use of imaging tests that can detect tumors incidentally.

Images

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  Clear-cell renal-cell carcinoma. Macroscopy
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  Clear-cell renal-cell carcinoma. HE, × 100
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  Clear-cell renal-cell carcinoma. Fuhrman grade = 1. HE, × 400