Extrarenal manifestations of renal cancer

Extrarenal manifestations of renal cancer include the following:

(1) Anemia: 20% to 40% of renal cancer patients suffer from anemia. Except for some patients with obvious hematuria, which causes visible blood loss, the rest of the patients suffer from anemia due to hematopoietic inhibition caused by tumor toxins, decreased erythropoietin and other factors.

(2) Abnormal liver function: In the absence of metastasis, abnormal liver function is called Stauffer's sign, which occurs in about 15% of patients. If the tumor is removed and liver function returns to normal, it indicates a good prognosis. Otherwise, there may be residual lesions or distant metastasis, which indicates a poor prognosis.

(3) Fever: About 30% of kidney cancer patients have varying degrees of fever, sometimes as high as 39°C or above, which may be related to pyrogens released by the tumor. For unexplained fever, especially in the elderly, the possibility of kidney cancer should be considered.

(4) Fatigue, weight loss, and cachexia: The incidence rate is about 33%. Since renal cancer is a tumor with relatively hidden symptoms and high malignancy, patients, especially those from rural areas, have obvious cachexia symptoms such as weight loss when they seek medical treatment.

In addition, there are many reports of renal cancer patients with hypertension, polycythemia and hypercalcemia, suggesting that renal cancer is also a tumor related to endocrine.