Tumors of the calyx and pelvic duct system

Tumors of the renal pelvis and calyceal system develop from the urothelium and in the overwhelming majority are cancers of varying degrees of malignancy; they are 10 times less common than tumors of the renal parenchyma.

Tumors of the renal pelvis and ureter arise from the transitional epithelium lining the upper urinary tract; they are usually exophytic papillary neoplasms.

Epidemiology

These neoplasms are relatively rare and account for 6-7% of primary renal tumors. The vast majority of them (82-90%) are transitional cell carcinoma; squamous cell carcinoma is observed in 10-17%, adenocarcinoma - in less than 1% of cases. The annual increase in incidence is about 3%, which may be due to deteriorating environmental conditions, although it may also be the result of improved diagnostics.

Men get sick 2-3 times more often than women, the age peak of incidence is in the 6th-7th decades of life. In childhood, these neoplasms are extremely rare. Tumors of the calyces and pelvis are diagnosed 2 times more often than tumors of the ureter. When localized in the ureter, its lower third is most often affected. Tumor formations can be solitary, but multifocal growth is more often recorded. Bilateral damage to the upper urinary tract is observed in 2-4% of cases, but it mainly develops in patients with Balkan nephropathy - a risk factor for this disease.

[ 1 ], [ 2 ], [ 3 ], [ 4 ], [ 5 ], [ 6 ], [ 7 ]

Causes tumors of the calyx and pelvic duct system

The causes of tumors of the renal pelvis and ureter, as well as bladder tumors, are largely known. The influence of environmental factors, the effect of which can be significantly delayed, has been established. These include exposure to aniline dyes, beta-naphthylamines. The incidence rate in this case increases by 70 times, and the average time period from the onset of exposure to tumor development is about 18 years.

Systematic use of phenacetin-containing analgesics for decades with the development of nephropathy increases the risk of such neoplasms by 150 times, and the time until the tumor appears can last up to 22 years. A prominent place in the development of the disease is occupied by Balkan endemic nephropathy: men and women, usually employed in agricultural production in Romania, Bulgaria, and the countries of the former Yugoslavia, suffer equally often; the latent period of the disease is up to 20 years; the peak incidence occurs in the 5th-6th decade of life. The risk of the disease in this endemic area is 100 times higher; tumors occur in 40% of people suffering from Balkan nephropathy. In 10% of cases, neoplasms are bilateral, most of them are poorly differentiated transitional cell carcinoma.

An important predisposing factor in the development of these tumors is contact with organic solvents, petroleum products, and automobile exhaust gases. Recent studies have shown that urban residents have a higher risk of disease than rural residents; in the city, drivers, auto repairmen, and traffic police officers are the most vulnerable. Smoking increases the risk of disease by 2.6-6.5 times in men and by 1.6-2.4 times in women compared to non-smokers. There may be a connection between the development of neoplasms and chronic inflammatory processes in the wall of the upper urinary tract.

Pathomorphological features of tumors of the renal pelvis and calyces system

Tumors are most often (82-90%) papillary neoplasms with the structure of transitional cell carcinoma of high (30%), medium (40%) and low (30%) differentiation, often with multicentric growth. 60-65% of neoplasms are located in the renal pelvis, 35-40% - in the ureter (15% in the upper and middle third and 70% in the lower third). According to the histological type, urothelial, squamous cell, epidermoid cancer and adenocarcinoma are distinguished.

Tumors metastasize lymphogenously to the nodes of the renal pedicle, paracaval (on the right), paraaortic (on the left), retroperitoneal, corresponding periureteral, iliac and pelvic. Lymph node involvement is an extremely unfavorable prognostic sign, while the outcome of the disease is little affected by the size, number and localization of lymphogenous metastases. There is a point of view on the possibility of implantation metastasis down the ureter into the bladder, but the intramural lymphogenous pathway is more likely. Tumors are insensitive to chemo- and radiation therapy and have an unfavorable prognosis.

[ 8 ], [ 9 ], [ 10 ]

Symptoms tumors of the calyx and pelvic duct system

Most patients report total macrohematuria with passage of worm-like clots. Hematuria may be initially painless, but with ureteral occlusion by clots it may be accompanied by an attack of pain similar to renal colic on the affected side, which stops as the clots pass. Constant dull aching pain is a sign of chronic obstruction of urine outflow with the development of hydronephrosis. In this case, bleeding into the lumen of the renal pelvis and calyces may be accompanied by the development of hematohydronephrosis with tamponade of the renal pelvis and calyces by blood clots, and the development of acute pyelonephritis.

The classic triad of symptoms described for renal tumors (hematuria, pain, palpable mass), as well as anorexia, weakness, weight loss, and anemia, indicate an advanced tumor and a poor prognosis for the disease. According to the literature, 10-25% of patients may not have any clinical symptoms.

Forms

The clinical classification was created to assess the depth of the lesion, the prevalence and severity of the cancer process. As with parenchymal tumors, the International Classification System TNM is adopted.

T (tumor) - primary tumor:

• Ta is a papillary noninvasive carcinoma.
• T1 - the tumor grows into the subepithelial connective tissue.
• T2 - the tumor grows into the muscular layer.
• TZ (pelvis) - the tumor grows into the peripelvic tissue and/or renal parenchyma.
• T3 (ureter) - the tumor grows into the periureteral tissue.
• T4 - the tumor grows into adjacent organs or through the kidney into the paranephric tissue.

N (nodnlus) - regional lymph nodes:

• N0 - there are no metastases in regional lymph nodes.
• N1 - metastasis in a single lymph node from 2 to 5 cm, multiple sizes no more than 5 cm.
• N3 - metastasis in a lymph node more than 5 cm.

M (metastes) - distant metastases:

• M0 - no distant metastases.
• Ml - distant metastases.

[ 11 ]

Diagnostics tumors of the calyx and pelvic duct system

Diagnosis of tumors of the renal pelvis and ureter is based on clinical, laboratory, ultrasound, X-ray, magnetic resonance, endoscopic and morphological data.

Laboratory tests and instrumental diagnostics of tumors of the renal pelvis and calyces system

The most common and persistent signs are microhematuria of varying intensity, associated false proteinuria, and detection of atypical cells in the urine sediment. Leukocyturia and bacteriuria indicate the addition of an inflammatory process, and hypoisosthenuria and azotemia indicate a decrease in the overall function of the kidneys. Repeated massive macrohematuria can cause anemia. An extremely unfavorable prognostic sign is an accelerated ESR.

Ultrasound diagnostics of tumors of the renal pelvis and calyces system

Indirect signs of a tumor are manifestations of impaired urine outflow in the form of hydronephrosis, pyelectasis and hydronephrosis in case of damage to the renal pelvis, ureterohydronephrosis in case of involvement of the ureter in the process. Against the background of expansion of the calyceal-pelvic system, parietal filling defects characteristic of an exophytic tumor can be detected. In the absence of an image of the calyces and pelvis, the informativeness of the study increases against the background of drug-induced polyuria after the administration of 10 mg of furosemide.

Endoluminal ultrasound examinations have recently begun to play an important role in diagnostics, significantly complementing endoscopic ones. A scanning sensor, resembling a ureteral catheter, can be passed along the ureter into the pelvis. The appearance of a parietal filling defect with changes in the underlying tissues allows not only to diagnose the neoplasm, but also to clarify the nature and depth of wall invasion.

X-ray diagnostics of tumors of the renal pelvis and calyces system

X-ray examinations are traditionally widely used in diagnostics of neoplasms of the upper urinary tract. Papillary tumors can be seen on a survey image only in cases of their calcification, usually against the background of necrosis and inflammation. On excretory urograms, the symptom of these tumors is a parietal filling defect on images in direct and semi-lateral projections, which should be differentiated from a radiolucent stone. Ultrasound examination is invaluable in this regard. The absence of signs of a calculus on ultrasound and a filling defect on the urogram are characteristic of a papillary tumor.

Computer tomography

Computer tomography is currently becoming increasingly important, especially with the introduction of multispiral CT, in the diagnostics of papillary neoplasms of the renal pelvis and ureter. Not only transverse contrasted sections at the level of the suspected lesion play an invaluable role in this, but also the ability to construct three-dimensional images of the upper urinary tract and so-called virtual endoscopy, which allows, using digital X-ray image processing technologies, to construct an image of the internal surface of a given segment of the upper urinary tract (calyx, renal pelvis, ureter).

[ 12 ], [ 13 ], [ 14 ]

Magnetic resonance imaging

The advantages of this method are the possibility of detailed analysis of images along the border of dense and liquid media, which is very effective in assessing filling defects in the renal pelvis. Obtaining very demonstrative and useful diagnostic information in papillary tumors of the upper urinary tract allows avoiding retrograde pyeloureterography, which is fraught with inflammatory complications.

Endoscopic examinations

Modern endoscopic diagnostics using thin rigid and flexible ureteropyeloscopes under general or spinal anesthesia allows to examine the inner surface of the cups, pelvis, ureter, bladder and urethra and in the vast majority of cases to see the neoplasm. Based on the condition of the mucous membrane covering the tumor and surrounding it, it is possible to visually assess the stage of the tumor process. Using special instruments, it is possible to perform a biopsy of the neoplasm, as well as, in the case of small superficial tumors, organ-preserving treatment - electrosurgical resection of the wall of the pelvis, ureter with removal of the tumor within healthy tissues using special miniature loops (endoscopic electroresection).

[ 15 ], [ 16 ], [ 17 ], [ 18 ]

Morphological studies

Cytological examination of centrifuged urine sediment may reveal atypical cells characteristic of transitional cell carcinoma. Histological examination of biopsy specimens obtained during endoscopy may identify the tumor.

Treatment tumors of the calyx and pelvic duct system

In addition to endoscopic electroresection, which is possible only for small superficial tumors and in large medical institutions equipped with special endoscopic and endosurgical equipment, the main method of treating papillary neoplasms of the upper urinary tract is surgery: the kidney and ureter are removed along their entire length and the urinary bladder is resected around the mouth of the corresponding ureter with the removal of fascia and regional lymph nodes. The scope of the operation is associated with the possible downward spread of the tumor in the form of daughter tumor formations along the ureter. If there are daughter tumors in the urinary bladder, they are removed endosurgically. Radiation and chemotherapy are ineffective in these patients.

Medical examination of patients with tumors of the renal pelvis and calyces

The clinical examination of patients who have undergone nephroureterectomy with bladder resection for papillary neoplasms of the upper urinary tract, in addition to examination, clinical blood and urine tests, must necessarily include cystoscopy every 3 months during the first year after surgery, every 6 months during the second and third years, and then once a year for life. Endoscopic examinations are aimed at promptly identifying and removing daughter tumors of the bladder, which may occur quite late after nephroureterectomy.

[ 19 ], [ 20 ], [ 21 ], [ 22 ]