Renal cell carcinoma in uremic acquired renal cystic disease: incidence, detection, and management

Increased Risk of Malignancy with Immunosuppression: A Population-Based Analysis of Texas Medicare Beneficiaries

Immunosuppressive drugs (IMD) are widely utilized to treat many autoimmune conditions and to prevent rejection in organ transplantation. Cancer has been associated with prolonged use of IMD in transplant patients. However, no detailed, systematic analysis of the risk of cancer has been performed in patients receiving IMD for any condition and duration. We analyzed Medicare data from Texas Medicare beneficiaries, regardless of their age, between 2007 and 2018, from the Texas Cancer Registry. We analyzed the data for the risk of cancer after IMD use associated with demographic characteristics, clinical conditions, and subsequent cancer type. Of 29,196 patients who used IMD for a variety of indications, 5684 developed cancer. The risk of cancer (standardized incidence ratio) was particularly high for liver (9.10), skin (7.95), lymphoma (4.89), and kidney (4.39). Patients receiving IMD had a four fold greater likelihood of developing cancer than the general population. This risk was higher within the first 3 years of IMD utilization and in patients younger than 65 years and minorities. This study shows that patients receiving IMD for any indications have a significantly increased risk of cancer, even with short-term use. Caution is needed for IMD use; in addition, an aggressive neoplastic diagnostic screening is warranted.

Incidence and Mortality of Renal Cell Carcinoma after Kidney Transplantation: A Meta-Analysis

Background: The incidence and mortality of renal cell carcinoma (RCC) after kidney transplantation (KTx) remain unclear. This study’s aims were (1) to investigate the pooled incidence/incidence trends, and (2) to assess the mortality/mortality trends in KTx patients with RCC. Methods: A literature search was conducted using the MEDLINE, EMBASE and Cochrane databases from inception through October 2018. Studies that reported the incidence or mortality of RCC among kidney transplant recipients were included. The pooled incidence and 95% CI were calculated using a random-effect model. The protocol for this meta-analysis is registered with PROSPERO; no. CRD42018108994. Results: A total of 22 observational studies with a total of 320,190 KTx patients were enrolled. Overall, the pooled estimated incidence of RCC after KTx was 0.7% (95% CI: 0.5–0.8%, I² = 93%). While the pooled estimated incidence of de novo RCC in the native kidney was 0.7% (95% CI: 0.6–0.9%, I² = 88%), the pooled estimated incidence of RCC in the allograft kidney was 0.2% (95% CI: 0.1–0.4%, I² = 64%). The pooled estimated mortality rate in KTx recipients with RCC was 15.0% (95% CI: 7.4–28.1%, I² = 80%) at a mean follow-up time of 42 months after RCC diagnosis. While meta-regression analysis showed a significant negative correlation between year of study and incidence of de novo RCC post-KTx (slopes = −0.05, p = 0.01), there were no significant correlations between the year of study and mortality of patients with RCC (p = 0.50). Egger’s regression asymmetry test was performed and showed no publication bias in all analyses. Conclusions: The overall estimated incidence of RCC after KTX was 0.7%. Although there has been a potential decrease in the incidence of RCC post-KTx, mortality in KTx patients with RCC has not decreased over time.

Imaging of renal cell carcinoma in patients with acquired cystic disease of the kidney: comparison 11C-choline and FDG PET/CT with dynamic contrast-enhanced CT

PURPOSE

To evaluate renal cell carcinoma (RCC) findings in acquired cystic disease of the kidney (ACDK) shown by ¹¹C-choline and FDG PET/CT, and contrast-enhanced CT.

MATERIALS AND METHODS

Six ACDK patients with 7 RCCs underwent ¹¹C-choline and FDG PET/CT, and contrast-enhanced CT before nephrectomy. Findings obtained with 3 imagings were evaluated and sensitivity detecting RCC was compared using 3-point grading scale (negative, equivocal, positive). The equivocal scale used for SUVmax ranged from 2.0 to 3.0 for PET/CT and a peak enhancement value ranging from 20 to 30 HU was used for CT.

RESULT

The histopathologic subtypes of 7 RCCs were clear-cell (n = 4) and ACD-associated RCC (n = 3). The negative/equivocal/positive grading results were 0/0/7 for ¹¹C-choline-PET/CT, 0/3/4 for FDG-PET/CT, and 2/2/3 for CT. Three equivocal cases by FDG-PET/CT were 2 clear-cell RCCs and 1 ACD-associated RCC. CT of 3 ACD-associated RCCs showed negativity for 2 and equivocality for 1. Sensitivity defining equivocal interpretation as negative for ¹¹C-choline-PET/CT, FDG-PET/CT, and CT was 100% (7/7), 57.1% (4/7), and 42.9% (3/7).

CONCLUSION

¹¹C-choline-PET/CT was more sensitive to detect RCC in ACDK as compared to FDG-PET/CT and contrast-enhanced CT in our series. FDG-PET/CT may be limited for detecting clear-cell RCC, while CT may have difficulty with detection of ACD-associated RCC.

Is there different risk of cancer among end-stage renal disease patients undergoing hemodialysis and peritoneal dialysis?

Cancer is a global issue in recent decade. Despite this alarming increase in the incidence of cancer, to date, whether the risk of developing cancer differs among peritoneal dialysis (PD) and hemodialysis (HD) patients is still uncertain. In this retrospective cohort study, data were obtained from the National Health Insurance Research Database of Taiwan, which provides coverage to almost 99% of the nation's population. After matching, a total of 4491 (or 3369) incident PD patients and 8982 (or 6738) incident HD patients between 2000 and 2009 were enrolled from the database. In addition, 22,455 (or 16,845) nondialysis patients were selected as a control group. The patients were monitored for the occurrence of cancer until 2010, and their data were analyzed using several different models. In general, the results showed that the risks of hepatocellular, kidney, bladder, extra kidney/bladder urinary tract, and thyroid cancers were higher in dialysis patients. We also compared the risk of cancer between two dialysis groups by using the HD patients as the reference group. The result showed that there is no significant different for each cancer risk between two dialysis groups. In conclusion, dialysis patients had a higher risk of certain types of cancer than those in the nonuremia group. However, there was no significant difference in the cancer risk between the two dialysis groups when compared directly.

Risk of chronic kidney disease after cancer nephrectomy

The incidence of early stage renal cell carcinoma (RCC) is increasing and observational studies have shown equivalent oncological outcomes of partial versus radical nephrectomy for stage I tumours. Population studies suggest that compared with radical nephrectomy, partial nephrectomy is associated with decreased mortality and a lower rate of postoperative decline in kidney function. However, rates of chronic kidney disease (CKD) in patients who have undergone nephrectomy might be higher than in the general population. The risks of new-onset or accelerated CKD and worsened survival after nephrectomy might be linked, as kidney insufficiency is a risk factor for cardiovascular disease and mortality. Nephron-sparing approaches have, therefore, been proposed as the standard of care for patients with type 1a tumours and as a viable option for those with type 1b tumours. However, prospective data on the incidence of de novo and accelerated CKD after cancer nephrectomy is lacking, and the only randomized trial to date was closed prematurely. Intrinsic abnormalities in non-neoplastic kidney parenchyma and comorbid conditions (including diabetes mellitus and hypertension) might increase the risks of CKD and RCC. More research is needed to better understand the risk of CKD post-nephrectomy, to develop and validate predictive scores for risk-stratification, and to optimize patient management.

Cancer risk among elderly persons with end-stage renal disease: a population-based case-control study

BACKGROUND

Patients with end-stage renal disease (ESRD) have elevated cancer risk. Cancer risk increases with age, but associations of ESRD with specific malignancies are incompletely studied for older individuals.

METHODS

We conducted a population-based case-control study (1,029,695 cancer and 99,610 controls) among the U.S. elderly using SEER-Medicare linked data. We defined ESRD as presence of dialysis claims in the 3 months prior to selection.

RESULTS

Although ESRD was not associated with excess cancer risk overall (odds ratio 1.02; 95%CI 0.91-1.14), risk was specifically increased for cancers of the stomach (1.45; 1.16-1.81), small intestine (1.92; 1.27-2.92), colon (1.17; 1.00-1.36), liver (1.53; 1.16-2.01), biliary tract (1.78; 1.20-2.65), lung (1.17; 1.02-1.34), cervix (2.12; 1.39-3.23), kidney (2.42; 2.01-2.92), and for multiple myeloma (1.77; 1.40-2.24) and chronic myeloid leukemia (1.74; 1.08-2.80). The association between liver cancer and ESRD was attenuated upon adjustment for hepatitis B and C infection or diabetes mellitus. Multiple myeloma risk was highest with short ESRD duration (p < 0.0001), possibly reflecting reverse causality, while kidney cancer risk showed a borderline rise over time (p = 0.08).

CONCLUSIONS

Among elderly individuals with ESRD, the excess risks for some cancers may reflect immune dysfunction or a high prevalence of other risk factors, such as viral infections or diabetes mellitus. Our results underscore the need for studying biological pathways of carcinogenesis in ESRD.

Spontaneous renal hemorrhage in hemodialysis patients

Dialysis patients have a tendency to bleed, and clinicians sometimes encounter cases with a significant amount of spontaneous hemorrhage. We herein report two cases of spontaneous renal hemorrhage in hemodialysis patients.

Insulin resistance and lower plasma adiponectin increase malignancy risk in nondiabetic continuous ambulatory peritoneal dialysis patients

End-stage renal disease patients have a higher risk for developing cancer. Although several causes for this increased risk have been proposed, the risk factors for cancer development in this population have not been elucidated. The aim of this study was to determine whether metabolic derangements, including insulin resistance and altered adipokines, increase the risk of developing malignancies in peritoneal dialysis (PD) patients, who are vulnerable to metabolic disorders because of excessive glucose absorbed from the dialysate. Study subjects comprised 106 nondiabetic PD patients who had been on PD for a minimum of 3 months with no overt malignancy. Baseline anthropometry, fasting glucose, insulin, and adiponectin were measured. The development of malignancy was evaluated during the follow-up period. During the mean follow-up of 47.0 ± 23.7 months, malignancy occurred in 15 patients (14.2%). The most common site of cancer was the kidney (26.7%), followed by thyroid (13.3%) and stomach (13.3%). Baseline insulin levels and homeostasis model assessment of insulin resistance were significantly higher, whereas plasma adiponectin levels were significantly lower, in patients who developed malignancy. Cox proportional hazards analysis revealed that insulin levels, homeostasis model assessment of insulin resistance, and lower adiponectin were independent predictors of malignancy. These findings demonstrate that insulin resistance and lower adiponectin levels could be risk factors for malignancy in nondiabetic PD patients.

Risk of malignancy with long-term immunosuppression in renal transplant recipients

BACKGROUND

Improvements in immunosuppressive regimens have significantly enhanced patient and graft survival in renal transplant recipients. However, susceptibility to neoplastic disorders is increased as a consequence of prolonged immunosuppression. Available data pertaining to cancer risks in renal transplant recipients have been inconsistent, and much of it is derived from international studies, which may not be truly representative of the United States population.

METHODS

We studied a total of 1979 transplants performed in 1739 patients from a single center in the United States with a mean follow-up of 6.1 years, and a total of 9852 person-years' follow-up.

RESULTS

The mean age at the time of diagnosis of cancer was 50 years, and the mean interval between transplant and diagnosis of cancer was 95 months. Older patients receiving a transplant had a significantly higher risk for developing cancer as opposed to younger patients (RR 6.2 for >60 years compared with <40 years). When compared with the general population using data from the Surveillance, Epidemiology and End Results (SEER) registry, the overall risk for nonskin malignancies was modestly increased in our transplant recipients, with a standardized incidence ratio (SIR) of 1.4 (P= 0.01). When stratified by age groups, younger age at transplant (<40 years) had the highest SIR, at 2.3 (P < 0.001). Similarly, duration post-transplant >10 years had an SIR of 2.4 (P < 0.001).

CONCLUSION

We believe that this study is representative of the United States' renal transplant population, and highlights the need for reduced immunosuppression in the long-term and increased vigilance for cancers in younger patients receiving renal transplantation.

Molecular Markers for Early Detection of Renal Carcinoma

Molecular markers for renal cell carcinoma could guide early detection of localized disease in defined populations at high risk for the disease or early disease recurrence after nephrectomy for renal cell carcinoma. In addition, sensitive and specific markers may provide surrogate end points for clinical trials of treatment and/or disease prevention. Powerful techniques of genomic and proteomic analysis of human renal carcinoma cell lines, tumor samples, and biological fluids, such as plasma and urine, obtained from patients with renal cell carcinoma, are likely to identify candidate markers. Careful selection among early candidate markers and further testing in independent patient populations are required for marker validation.

Concurrent renal cell carcinoma and transitional cell carcinoma in a chronic hemodialysis patient

A 60-year-old female patient had been on maintenance hemodialysis for 12 years was suffering from gross hematuria. Subsequent image studies revealed left renal and ureteral tumors. She then received left radical nephroureterectomy. Histological examination revealed the renal tumor was renal cell carcinoma and ureteral tumor was transitional cell carcinoma respectively. To our knowledge, this is the first reported case of simultaneous occurrence of these two urological cancers in a chronic hemodialysis patient. Our case may imply the increased susceptibility of urological malignancy in dialysis patients. Physicians should always raise the possibility of urological malignancy when a dialysis patient with gross hematuria is encountered. A thorough and careful screening for the malignancy should be performed on a regular basis in these patients with high risk.

Hyperparathyroidism and subsequent cancer risk in Denmark

BACKGROUND

There is increasing evidence that hyperparathyroidism (HPT), a condition that leads to elevated serum calcium levels, is associated with endocrine and other malignancies, suggesting a possible causal link between HPT and carcinoma.

METHODS

To investigate the relation of HPT to subsequent cancer risk, the authors conducted a record-linkage study among 2425 patients who were diagnosed with HPT in Danish hospitals. Patients were identified in hospital discharge records, and records were then linked with the Danish National Cancer Registry for the years 1977-1993 to identify cancer incidence. To estimate cancer risk, standardized incidence ratios (SIRs) were computed.

RESULTS

After excluding patients who were diagnosed in the first year of follow-up, a total of 219 malignancies were observed, resulting in an SIR of 1.25 (95% confidence interval [95%CI], 1.1-1.4). Cancer risk among women was higher than among men. Among those with primary (idiopathic) HPT, hematopoetic malignancies were elevated significantly (SIR, 1.88; 95%CI, 1.0-3.2; based on 13 patients), with the excess derived primarily from 4 observed patients with multiple myeloma. Patients with secondary HPT had an insignificantly increased risk of overall cancers. Patients who were diagnosed with other or unspecified types of HPT had significant increases in carcinoma of the urinary tract (SIR, 2.71; 95%CI, 1.2-5.3; based on 8 patients) and carcinoma of the thyroid gland (SIR, 21.19; 95%CI, 4.3-61.9; based on 3 patients).

CONCLUSIONS

Future studies should monitor whether specific endocrine alterations associated with HPT may affect the long-term risk of hematopoetic, thyroid, and urinary tract carcinomas.

Cancer in patients on dialysis for end-stage renal disease: an international collaborative study

BACKGROUND

Previous studies have suggested that the frequency of cancer is higher in patients with end-stage renal disease (ESRD) than in the general population, but have not established whether this increase is confined to certain cancers or to certain categories of ESRD patients. The aim of this study was to examine the risk of cancer in a large cohort of patients treated by dialysis but not transplantation.

METHODS

We assembled a cohort of 831,804 patients who received dialysis during the period 1980-94 for ESRD in the USA, Europe, Australia, or New Zealand. We compared the observed frequency of cancer among these patients during 2,045,035 person-years of follow-up with the frequency of cancer in the respective background populations.

FINDINGS

During average follow-up of 2.5 years, 25,044 (3%) of 831,804 patients developed cancer compared with an expected number of 21,185 (standardised incidence ratio 1.18 [95% CI 1.17-1.20]). We observed a higher risk of cancer in patients younger than 35 years (3.68 [3.39-3.99]), and the risk gradually decreased with increasing age. High risks were observed for cancer of the kidney (3.60 [3.45-3.76]), bladder (1.50 [1.42-1.57]), and thyroid and other endocrine organs (2.28 [2.03-2.54]). Excess cancers appeared in several organs for which viruses have been suspected as causative agents, whereas cancers of the lung, colorectum, prostate, breast, and stomach were not consistently increased.

INTERPRETATION

The overall risk of cancer is increased in patients with ESRD, and the distribution of tumour types resembles the pattern seen after transplantation (although we have no data to make the comparison with skin cancer). The excess risk can largely be ascribed to effects of underlying renal or urinary-tract disease, or of loss of renal function, on the kidney and bladder, and to increased susceptibility to viral carcinogenesis. The relative risk, which is especially high in younger patients, gradually diminishes with age.

Cytokine levels in cystic renal masses associated with renal cell carcinoma

PURPOSE

We compared cytokine levels in fluid from renal cysts with and without renal cell carcinoma.

MATERIALS AND METHODS

Fluid was aspirated from 18 renal cysts without (benign) and 21 with renal cell carcinoma (malignant). Serum from patients with renal cell carcinoma and healthy controls was collected and cytokines were measured by enzyme-linked immunosorbent assay.

RESULTS

Interleukin-6 (IL-6) and basic fibroblast growth factor concentrations were higher in malignant than benign cysts or serum (p <0.006). Epidermal growth factor levels were significantly higher in malignant cysts and serum than in benign cysts (p <0.01). IL-6 levels in malignant cysts positively correlated with the erythrocyte sedimentation rate (R=0.80) and C-reactive protein (R=0.86), and they were higher in grade 3 than in grade 2 tumors. Basic fibroblast growth factor levels were significantly higher in malignant cysts associated with hypervascular than hypovascular tumors (p=0.029).

CONCLUSIONS

Cytokine levels in aspirated fluid may help to identify malignant renal cysts and indicate the characteristics of coexisting tumors.

Role of magnetic resonance imaging in renal transplant recipients with acquired cystic kidney disease

OBJECTIVES

To evaluate the impact of magnetic resonance imaging (MRI) in renal transplant recipients whose ultrasound (US) examinations of the native kidneys have met the criteria of acquired cystic kidney disease (ACKD).

METHODS

The US scans of 840 renal allograft recipients were prospectively studied. In addition, 46 of 169 patients diagnosed with ACKD by US scans underwent MR examination. MRI protocols included (a) T1 and T2-weighted fast spin echo imaging, (b) T2-weighted gradient echo imaging, and (c) gadolinium-enhanced T1-weighted imaging in 7 patients with evidence of complex cysts. In the case of complex lesions, both US and MRI follow-up examinations were performed between 6 and 12 months after the prior examination.

RESULTS

US examination showed ACKD in 169 of 840 patients. In addition, US revealed 8 patients with renal cell carcinomas (RCC). Of these 8 patients, 7 had evidence of ACKD. The median number of cysts depicted on US examination in native kidneys of renal transplant recipients was 3 (range 0 to 10) on both sides. MRI revealed significantly more and smaller cysts compared to US. The median number of cysts was seven on the left and nine on the right native kidneys, respectively. MRI revealed 18 complex lesions in 7 patients. Thirteen of 18 complex lesions were undetected by US.

CONCLUSIONS

MRI is superior to US in depiction of simple and complex lesions of native kidneys in renal allograft recipients. MRI exhibits no overestimation of the prevalence of ACKD on the basis of the US criteria already mentioned. Advantages of MRI do not justify routine screening tests by this imaging modality. However, MRI should be used for further evaluation of complex lesions detected by US.

Current concepts and controversies in imaging of renal cystic diseases

Renal cystic disease compromises a diverse group of inherited and acquired entities. This article reviews the clinical, pathologic, and radiologic findings of eight renal cystic diseases. For each entity, the current concepts of pathogenesis and pathophysiology are discussed. When appropriate, controversies concerning terminology, management, and malignant potentials are addressed. Renal cystic diseases that are discussed include autosomal dominant and autosomal recessive polycystic kidney disease, medullary sponge kidney, medullary cystic disease, multicystic, dysplastic kidney, von Hippel-Lindau disease, acquired cystic kidney disease, and tuberous sclerosis.

Cancer among patients on renal replacement therapy: a population-based survey in Lombardy, Italy

Longer and better survival of End-Stage Renal Disease (ESRD) patients undergoing renal replacement therapy (RRT) is now associated with a higher prevalence of new elderly patients receiving renal replacement therapy (dialysis). In order to help clarify the association of cancer risk with RRT, the incidence of cancer in a population-based cohort of uraemic patients in the Region of Lombardy, northern Italy, was undertaken using data from the Lombardy Regional Dialysis and Renal Transplant Registry. A total of 479 cases of cancer of all sites was recorded in this population. There were statistically significantly elevated risks of primary liver cancer, kidney cancer, thyroid cancer, lymphoma and multiple myeloma. When the data were examined according to primary renal diseases, there did not appear to be any particular association between excess cancer risk and the underlying pathology. While some caution must be expressed in interpreting these data, due to the relatively small numbers of cases expected in many of the disease entities, the results indicate an excess of renal-cell and liver carcinomas and lymphomas in patients receiving RRT and highlight the necessity of careful follow-up and awareness of these associations, together with the need for early detection of such tumours.

Patients with renal cysts associated with renal cell carcinoma and the clinical implications of cyst puncture: a study of 223 cases

OBJECTIVES

To clarify the association between renal cysts and renal cell carcinoma (RCC), we analyzed patient demographics, types of cystic disease, and modes of cyst-tumor coexistence along with the results of cyst puncture.

METHODS

A total of 507 hospitals provided information regarding clinical experiences with RCC and cyst puncture over a 2-year period.

RESULTS

Renal cysts were identified by preoperative imaging in 223 (4%) of 5721 patients with RCC. Histologic examination revealed cystic RCC in 56 patients (25%) and RCC associated with cystic diseases in 167 (75%). Cystic disease included simple cysts in 72 patients (32%), acquired cystic disease of the kidney (ACDK) in 62 (28%), multilocular renal cysts in 20 (9%), polycystic kidney in 3 (1%), and unspecified or miscellaneous in 10. Cyst puncture performed in 47 (21%) of 223 patients demonstrated bloody fluid in 20 cases and nonbloody fluid in 27. Cytologic analysis of cystic fluid obtained from 37 patients revealed a malignancy in 5 (14%), accounting for 25% of the bloody and 4.8% of nonbloody specimens. Cytology failed to detect RCC in ACDK and multilocular cysts but was positive in cases of cystic RCC and solitary cysts. Four of 5 cytology-positive cases comprised those of tumor in cyst and cyst within tumor.

CONCLUSIONS

Simple cysts and ACDK accounted for 60% of the renal cysts associated with RCC. Cystic RCC was involved in 25% of cases. Positive cytology may be expected in select cases, including those with close cyst-tumor relationships and those involving bloody cyst fluid. However, negative cytology does not exclude RCC.

Polycystic kidney disease: etiology, pathogenesis, and treatment

Once viewed as hopelessly incurable disorders and the dustbin for careers in academic medicine, the polycystic kidney diseases have emerged as prime targets of pathophysiologic study and palliative and definitive treatment in the era of molecular medicine. Polycystic kidney disease (PKD) may be hereditary or acquired. The major inherited types are autosomal dominant (AD) and autosomal recessive (AR). ADPKD is caused by at least two (and possibly three) genes located on separate chromosomes, while ADPKD-1 is due to a 14 kb transcript in a duplicated region on the short arm of chromosome 16 very near the alpha-globin gene cluster and the gene for one form of tuberous sclerosis. ADPKD-2 has been assigned to the long arm of chromosome 4. ARPKD is due to a mutated gene on both copies of the long arm of chromosome 6. Cysts originate in renal tubules. Proliferation of tubule epithelial cells modulated by endocrine, paracrine, and autocrine factors is a major element in the pathogenesis of renal cystic diseases. In addition, fluid that is abnormally accumulated within the cysts is derived from glomerular filtrate and, to a greater extent, by transepithelial fluid secretion. Abnormal synthesis and degradation of matrix components associated with interstitial inflammation are additional features in the pathogenesis of renal cystic diseases. The ADPKD genotypes are characterized by bilateral kidney cysts, hypertension, hematuria, renal infection, stones, and renal insufficiency. ADPKD is a systemic disorder; cysts appear with decreasing frequency in the kidneys, liver, pancreas, brain, spleen, ovaries, and testis. Cardiac valvular disorders, abdominal and inguinal hernias, and aneurysms of cerebral and coronary arteries and aorta are also associated with ADPKD. Treatment is supportive: dietary regulation of salt and protein intake, control of hypertension and renal stones, and dialysis and transplantation at the end stage. ARPKD is a relatively rare disease that causes clinical symptoms at birth, with significant mortality in the first month of life. The cysts develop primarily in the collecting ducts because of a failure in the maturation process. Early complications include Potter's syndrome; excessive size of the kidneys, causing respiratory dysfunction; hypertension; and renal insufficiency. Hepatic fibrosis is an associated extrarenal problem that results in significant morbidity in young children and adolescents. Treatment includes supportive care, dialysis, and renal transplantation. Acquired cysts (solitary/simple) are commonplace in older persons. Multiple cysts may be seen in association with potassium deficiency, congenital disorders, metabolic diseases, and toxic renal injury.(ABSTRACT TRUNCATED AT 400 WORDS)

Renal neoplasm in acquired cystic kidney disease

The development of renal cell neoplasms ranging from adenoma to metastatic carcinoma is the most serious complication of acquired cystic kidney disease (ACKD). A comprehensive review of the pertinent literature shows that there is up to 50-fold increased risk of renal cell carcinoma in ACKD compared to the general population. The ACKD-associated renal cell carcinoma is seen predominantly in males, occurs approximately 20 years earlier than in the general population, and is frequently bilateral (9%) and multicentric (50%). Acquired cystic kidney disease-associated renal cell carcinoma is frequently asymptomatic (86%), but may be associated with bleeding, abrupt changes in hematocrit, fever, and flank pain or rarely with hypoglycemia, hypercalcemia, or metastases at presentation. Computed tomography seems to provide a better diagnostic yield than sonography or magnetic resonance imaging; nevertheless, large (up to 8 cm) tumors not visualized by any imaging techniques have been reported. It is generally agreed that there is a need for regular screening of symptomatic ACKD patients for early detection of renal cell carcinoma; however, whether screening is needed for asymptomatic patients remains controversial. Nephrectomy is indicated for tumors larger than 3 cm. Management for tumors smaller than 3 cm with persistent symptoms, such as back pain or hematuria, remains controversial, but nephrectomy may be recommended since many of these tumors turn out to be unequivocal renal cell carcinoma. Asymptomatic tumors smaller than 3 cm should be serially screened, and tumor enlargement may be an indication for nephrectomy. Acquired cystic kidney disease-associated renal cell carcinoma accounts for approximately 2% of deaths in renal transplant patients. A median length of survival of approximately 14 months and a 5-year survival rate of 35% are comparable to the same data for renal cell carcinoma in the general population. Successful renal transplant probably decreases the risk of renal cell carcinoma in ACKD patients, but this preliminary observation needs confirmation. The development of ACKD-associated renal carcinoma is a continuous process with evolving phenotypic expression, including damaged renal tubule, simple cyst, cyst with atypical lining, adenoma, and, finally, carcinoma. The pathogenesis of this continuous process is not entirely known, but growth factor-induced compensatory growth of tubular epithelium initiated by the changes of end-stage kidney disease, and probably perpetuated by activation of proto-oncogenes, seems to be the most significant factor.

Renal cell carcinoma in a natural remaining kidney after two kidney transplantations. Case report

A 57-year-old woman with nephropathy following a streptococcal infection had received a kidney transplant in 1980 and 1986 and immunosuppressive treatment since 1980. Renal cell carcinoma was found in the right native kidney in 1991, with skeletal metastases. Nephrectomy was performed and radiotherapy given. Removal of non-functioning kidneys would prevent development of such cancer.

Renal cell carcinoma in patients with acquired cystic renal disease. A case report

A patient with renal cell carcinoma in primitive kidney with acquired cystic renal disease following hemodialysis for 9 years was discovered during a routine ultrasonographic follow-up. Differences with these tumors in transplanted patients are stressed.