Tubular kidney carcinoma is a type of kidney cancer originating from the renal tubules (Henle loops). The symptoms of the disease are similar to other types of cancer. There is hematuria, soreness and palpable swelling in the projection of the kidney, anemia, intoxication. Diagnosis of pathology is carried out on the basis of laboratory tests, ultrasound of the kidneys, urography, aortography, nephroscintigraphy, CT, MRI. The main method of treatment is surgical. Total nephrectomy is performed, with gross violations of the function of the paired kidney, the affected area of the organ is removed.
Meaning
Tubular carcinoma of the kidney (tubular cancer, cancer of the renal tubules of Bellini), according to the observations of practical oncourologists, occurs in less than 1% of cases of malignant kidney lesions. Tubular carcinoma refers to tumors with a malignancy potential above average. Like other types of kidney cancer, neoplasia is approximately 2-3 times more common in men aged 40-60 years.
Causes
The etiology of tubular kidney carcinoma has not been fully studied. Factors that increase the likelihood of developing the disease include genetic defects in chromosomes, immunodeficiency states, obesity, prolonged hemodialysis, hereditary diseases (Hippel-Lindau disease), exposure to ionizing radiation, smoking, chemical and drug intoxication.
Pathanatomy
Microscopically, tubular carcinoma contains tubular and papillary structures lined with single-layer cubic epithelial cells and creating a picture of the so-called “cobblestone pavement”. The growth of the tumor node is rapidly progressing, having no clear boundaries with the spread to the medulla and papillae. Macroscopically, on the incision, the carcinoma has the appearance of a light gray node with massive foci of necrosis.
Symptoms
Pathology can develop asymptomatically for a long time and manifest itself clinically only at late, difficult-to-treat stages. A general nonspecific sign may be a deterioration in general well-being, which is a consequence of tumor intoxication. Often patients note causeless weakness, decreased appetite and activity, weight loss, arthralgia. Subfebrility is often noted, sometimes the body temperature rises to 38-39 ° C, accompanied by chills, which is often perceived as an infectious disease. 5-10% of patients with tubular renal carcinoma develop arterial hypertension.
Local manifestations of kidney cancer are hematuria, pain in the lower back and a tumor determined by touch. Hematuria is pain-free, which distinguishes it from a similar symptom with kidney stones. Blood in the urine, as a rule, appears suddenly, against the background of a general satisfactory condition, and just as unexpectedly disappears on its own. The blood clots formed during bleeding can cause obstruction of the ureter and lead to the development of a painful attack that proceeds according to the type of renal colic. Lower back pain is dull, aching, sometimes radiating into the hip or groin. Palpable tumor in kidney cancer is characteristic, but the most recent of the triad of local symptoms.
Complications
With severe hematuria, there is a high probability of bladder tamponade and acute urinary retention. Sometimes there is a varicocele, which can occur in men when a tumor sprouts or inflection of the left renal vein, compression of the inferior vena cava or testicular vein, thrombosis of the inferior vena cava.
Metastasis of tubular kidney carcinoma more often occurs in the lungs, is accompanied by hemoptysis and is often mistaken for bronchogenic cancer, pneumonia or pulmonary tuberculosis. Bone metastases are manifested by persistent intense pain, often regarded as manifestations of sciatica or intercostal neuralgia. Metastatic spinal lesion is accompanied by lower paraplegia, a violation of the functioning of the pelvic organs. Metastases to the tubular bones can lead to pathological fractures. Regional metastases are detected in paraaortic and paracaval lymph nodes.
Diagnostics
Examination and palpation can reveal only large tumors. At the same time, there may be an increase and asymmetry of the abdomen, dilation of the abdominal wall veins, varicocele, swelling of the legs. The study of the general urinalysis reveals erythrocyturia, proteinuria, leukocyturia (when cancer is combined with pyelonephritis). In the biochemical study of blood, attention is drawn to an increase in the activity of alkaline phosphatase, the level of a2-globulin. With the help of immunological tests, violations of the metabolism of serum proteins (ferritin, albumin, transferrin, etc.) are detected.
The screening method for diagnosing tumors in modern oncourology is ultrasound of the kidneys, which allows detecting deformation of the contours of the affected kidney and its uneven echostructure. Ultrasound helps to differentiate kidney cancer with hydronephrosis, pionephrosis, nephrolithiasis, polycystic kidney disease, abscess, kidney tuberculosis, solitary cyst.
X-ray diagnostics in case of suspected kidney cancer begin with performing an overview urography, which allows you to see changes in the size and configuration of the kidney. With the help of excretory urography, the morphological and functional state of the kidneys is clarified. Renal angiography is performed to determine the vascularization of the affected organ. Nephroscintigraphy, MRI and CT of the kidneys play an important role in the diagnostic complex. A kidney biopsy is usually not performed due to the high risk of cancer cell dissemination.
Treatment
Surgical treatment is indicated even in the presence of single metastases. Radical surgery can significantly prolong the patient’s life. The standard volume for tubular carcinoma is total nephrectomy with adrenalectomy, lymphodissection and removal of tumor clots from the renal and inferior vena cava. With a single kidney or an unsatisfactory function of the second organ, partial nephrectomy is possible. Due to the resistance of tubular kidney carcinoma to radiation therapy, systemic chemotherapy, immunochemotherapy, these methods are indicated only as palliative care.