Kidney tumors can have a variety of clinical manifestations, but it should be emphasized that no one symptom or manifestation is unique to kidney tumors, and conversely, not every kidney tumor patient will exhibit all symptoms at the same time. In fact, due to the development of health care and improvement of medical treatment nowadays, more than half of kidney tumors are detected by regular medical checkups and patients do not have any symptoms. Therefore, it is very important to attend the annual health check-up regularly for early detection of kidney tumors. 1.Hematuria The kidney is deeply hidden in the retroperitoneal space, surrounded by the organs in the abdominal cavity and the abundant lumbar back muscles gap, and surrounded by the organs in the abdominal cavity and the abundant lumbar back muscles, so the kidney tumor often lacks early clinical manifestations. The kidney can relate to the outside world through its primary product – urine. Therefore, hematuria is one of the most common clinical symptoms of renal cell carcinoma, which is caused by tumor invading the mucosa of renal pelvis or calyces. Forty to 60% of kidney cancer patients will have varying degrees of hematuria, which is usually intermittent throughout painless carnal hematuria, or may be due to other reasons when Nam Cheong performs urine examination and finds abnormally increased red blood cells in the urine. Sometimes patients will have strips of blood clots excreted with the urine, this is because the picture coming out from the tumor is clotted in the lumen of the ureter into strips, which is called ureteral tubular pattern. The blood clot can cause renal colic when it blocks the ureter. It should be noted that the hematuria caused by kidney tumor is often intermittent and transient, and may stop on its own without treatment, which often causes patients to neglect the surface and delay the diagnosis and treatment. Generally speaking, patients over 40 years of age with painless hematuria should be examined to exclude kidney tumors. 2.Lower back pain Low back pain is a very common clinical symptom related to a variety of diseases and work sports and other factors. Therefore, low back is not a unique manifestation of kidney tumor, and not all kidney tumor patients will have the symptoms of low back pain. The pain caused by kidney tumor is mostly unilateral lumbar pain, which is dull in nature, with an incidence of about 20%. In a few cases, renal colic may occur when the tumor causes severe hematuria and blood clots causing ureteral obstruction, and the pain is very severe, but the pain will be relieved immediately when the clots causing obstruction are discharged. Some kidney tumor patients can feel the mass in the abdomen, and it is more likely to appear in long and lean body type. The mass is located under the rib cage of upper abdomen and can move up and down with breathing movement. Because of the lack of early symptoms of kidney tumor, it is often detected when the tumor grows to a large size and the patient may not feel any discomfort at that time. Nearly 20% of patients may present with an abdominal mass, with about one-third of them presenting with only an abdominal mass. The so-called abdominal mass may be the tumor itself, or it may be the lower pole of the kidney that has been pushed down by the tumor. The first mass felt by the patient is often the tumor itself, while the lower pole of the kidney is more likely to be palpated by the physician. If the tumor is fixed, it means that the tumor may have invaded the surrounding organs of the kidney, and the prognosis of these patients may be poor due to the difficulty in removing the tumor. 4.Low fever Some patients with kidney cancer will have afternoon low fever, usually below 37.8℃, with an incidence of about 10%-15%. In the past, it is believed that for some tumors with rapid growth, part of the tumor body is necrotic or liquefied because it cannot get sufficient nutrition supply, in which there are pyrogenic sources that can cause fever, and when this part of material is absorbed by the body, it will bring the manifestation of hypothermia. Therefore, it is thought that patients with renal tumors that show hypothermia have faster tumor growth and may have poor prognosis. However, some scholars have recently found that 25% of kidney tumors can ectopically secrete a substance called interleukin-6, and this ectopically secreted interleukin-6 may be related to fever, so hypothermia is not necessarily evidence of poor prognosis. 5. Hypertension About 20% of kidney cancer patients have the manifestation of hypertension. Kidney is not only an important metabolic organ in human body, but also an important endocrine organ, which plays an important role in blood pressure regulation through renin-angiotensin-aldosterone system and cardiac natriuretic system with the body. Excessive renin secretion due to renal tumors, intra-tumor arteriovenous fistulae, and tumor compression of renal vessels may all contribute to the elevated blood pressure in patients. However, recent epidemiological investigations have shown that hypertensive disease itself may also be responsible for the development of renal tumors. Therefore, only hypertension that returns to normal after removal of renal tumor can be said to be caused by renal tumor. 6, varicocele The reflux vein of male testis is called spermatic vein, because it has to flow back directly from the low testis to the inferior vena cava below the right kidney vein, and the left side is even flowing back directly into the left kidney vein, the blood has a long journey in the spermatic vein. When the blood flow is obstructed, it will cause the varicose expansion of the spermatic vein, which is manifested by the swelling of the scrotum, with a feeling of heaviness and swelling, and the varicose veins can be felt in the scrotum in a worm-like mass. When the patient lies down, the pressure of venous return decreases, the varicose veins naturally subside, and the symptoms disappear. This disease is very common in men, and 10% to 15% of young adults may have some disease, most of which do not require treatment. In some cases, the kidney tumor can grow into the renal vein or even the inferior vein, which seriously affects the blood return in the spermatic vein. Moreover, when the patient lies down, the pressure in the vein does not decrease with the change of body recuperation, so it becomes an important feature of varicose veins caused by kidney tumor that does not disappear after some lying down position.