[Small renal cell carcinomas and synchronous metastases]. / Litil nyrnafrumukrabbamein og fjarmeinvorp.

OBJECTIVE: The incidence of renal cell carcinoma (RCC) is rising in part due to small tumors (≤4cm) detected incidentally with abdominal imaging. Survival for small RCCs has been regarded as favorable and guidelines recommend partial rather than total nephrecteomy. We studied the frequency of synchronous metastasis in patients with small RCCs in Iceland. MATERIALS AND METHODS: A retrospective study on 257 patients with RCC ≤4cm out of 1102 RCC patients diagnosed in Iceland 1971-2010. Patients with metastasis were compared to those with localized disease. Hospital charts were reviewed and histology, TNM-stage and disease-specific survival compared between groups. RESULTS: The proportion of small tumors increased from 9% in 1971-1980 to 33% in 2001-2010 (p<0,001) and incidental detection increased from 14% to 39% during the same period. Out of the 257 patients with small RCCs, 25 (10%) had synchronous metastases, most frequently in lungs or bones. Patients with metastases were on average 1.9 years older, their tumors were 0.2 cm larger and more often located in the right kidney, their hemoglobin was lower and nuclear grade and T-stage higher. Histology was similar in both groups. Five-year survival of patients with and without metastases was 7 vs. 94%, respectively (p<0.001). CONCLUSIONS: One out of ten patients with small RCC has synchronous metastases at diagnosis. This is higher than in most previous reports that usually include surgical patients only. Patients with metastases are significantly older, more often symptomatic, their tumor are larger and their prognosis worse. Our results indicate that small RCC is a potentially systemic disease at diagnosis that has to be taken seriously.

Incidental detection of renal cell carcinoma is an independent prognostic marker: results of a long-term, whole population study.

PURPOSE: The true effect of incidental detection on the survival of patients with renal cell carcinoma has been debated. We used centralized databases in Iceland to study prognostic factors of survival, focusing on the effect of incidental detection. MATERIALS AND METHODS: This retrospective study included all living patients diagnosed with renal cell carcinoma in Iceland from 1971 to 2005. Hospital charts and histology were reviewed. Incidentally diagnosed renal cell carcinomas were compared to symptomatic tumors and prognostic factors were evaluated using Cox multivariate analysis. RESULTS: Of the 910 patients 254 (27.9%) were diagnosed incidentally, most often by abdominal ultrasound (29.5%) or computerized tomography (28.3%). The incidental detection rate increased from 11.1% in 1971 through 1975 to 39.2% in 2001 through 2005 (p <0.001). During the same period the incidence increased significantly in males but in females only during the last 5 study years. Mortality remained unchanged for each gender. Incidentally detected tumors were an average of 2.6 cm smaller and diagnosed at lower stage and lower grade than symptomatic tumors. Age and histology were similar in each group. TNM stage was by far the strongest independent prognostic factor of survival but age, calendar year of diagnosis and ESR were also significant. After correcting for confounders patients with symptomatic renal cell carcinoma had worse survival than those diagnosed incidentally. CONCLUSIONS: With increased incidence and unchanged mortality the survival of patients with renal cell carcinoma has improved. This is mainly related to a steep increase in incidental detection. Incidental detection affects survival favorably and to a greater extent than can be explained by lower stage compared to the survival of patients diagnosed with symptoms.

[Renal cell carcinoma diagnosed at autopsy in Iceland 1971-2005]. / Nýrnafrumukrabbamein greind vid krufningu á Islandi 1971-2005: Samanburdur vid aexli greind í sjúklingum á lífi.

INTRODUCTION: The incidence of renal cell carcinoma (RCC) is rising in Iceland. This has been attributed to increased diagnostic activity, such as abdominal imaging of unrelated diseases, rather than changes in the behavior of the disease. The aim of this study was to compare RCCs diagnosed in living patients and at autopsy, but also to investigate the relationship between the incidence of RCC and autopsy findings. MATERIAL AND METHODS: RCC found incidentally in individuals at autopsy was compared to patients diagnosed alive over three decades in Iceland (1971-2005). Stage at diagnosis and tumor histology was reviewed. RESULTS: 110 tumors were diagnosed at autopsy with a rate of 7.1/1000 autopsies. When compared to patients diagnosed alive (n = 913) the mean age at diagnosis was higher in the autopsy group (74.4 vs. 65 yrs.) while male to female ratio and laterality was similar. Tumors found at autopsy were smaller (3.7 vs. 7.3 cm), at lower stage (88% at stage I+II vs. 42%) and at lower tumor grade (85% at grade I+II vs. 56%). A difference, although smaller, is present when the autopsy detected cases are compared to only incidentally detected RCCs in living patients. Furthermore the autopsy detected tumors were more frequently of papillary cell type (21% vs. 8%). After correcting for declining autospy rate (>50%), a slight trend for a reduced rate of autopsy dectected RCC cases was seen during the last 10 years of the period but the difference was not significant. CONCLUSION: RCCs diagnosed at autopsy are at a lower stage and tumor grade than in patients diagnosed alive. The autopsy-rate is declining in Iceland with fewer RCCs found per autopsy. After correcting for the decline in autopsy rate, the rate of RCC detected at autopsy is relatively unchanged. The increase in incidence of RCC is therefore not explained by findings at autopsy.