The natural history of incidentally detected small renal masses.

BACKGROUND: The incidence of renal cell carcinoma (RCC) is increasing, largely due to the widespread use of cross-sectional imaging. Most renal tumors are detected incidentally as small, asymptomatic masses. To study their natural history, the authors prospectively followed a series of patients with this type of lesion who were unsuited for or refused surgery. METHODS: Twenty-nine patients with 32 masses that measured < 4 cm in greatest dimension (25 solid masses and 7 complex cystic masses) were studied. The primary outcome was tumor size, which was calculated as volume over time. All patients were followed with serial abdominal imaging, and each mass had at least three follow-up measurements. The median follow-up was 27.9 months (range, 5.3-143.0 months). RESULTS: Overall, the average growth rate did not differ statistically from zero growth (P = 0.09; 95% confidence interval, - 0.005-0.2 cm per year) and was not associated with either initial size (P = 0.28) or mass type (P = 0.41). Seven masses (22%) reached 4 cm in greatest dimension after 12-85 months of follow-up. Eight masses (25%) doubled their volumes within 12 months. Overall, 11 masses (34%) fulfilled 1 of these 2 criteria of rapid growth. Nine tumors were removed surgically after an average of 3.1 years of follow-up because it was believed that they were growing fast. No patient had disease progression. CONCLUSIONS: Approximately one-third of small renal masses that are presumed RCCs grow if they are managed conservatively and are followed with serial imaging. The growth rate is slow or undetectable in the majority of patients. These observations raise the possibility of a period of initial observation in selected patients, particularly the elderly or infirm.

Prostate cancer grade assignment: the effect of chronological, interpretive and translation bias.

PURPOSE: Surveillance, Epidemiology and End Results (SEER) data reveal an increasing incidence in the detection of moderately differentiated prostate cancer and a stable or decreasing incidence in well and poorly differentiated cancer. Plausible reasons for this phenomenon include the decrease in transurethral resections performed and an increase in the number of prostate specific antigen triggered ultrasound guided needle biopsies. We examined additional explanations for the grade shift with time and addresses the impact of this grade shift on clinical end points. MATERIALS AND METHODS: Archived slides from 100 patients (82 needle biopsy specimens and 18 transurethral resection specimens) treated for prostate cancer between 1975 and 1985 were reexamined. Current grades were assigned using the WHO and the Gleason grading systems, and they were compared with the original grade assignments. Current Gleason score was translated to WHO grade by operational SEER criteria (2 to 4-well, 5 to 7-moderately and 8 to 10-poorly differentiated). Analysis of the 100 specimens by life table methodology calculated cancer specific survival according to the era of grade assignment. RESULTS: There was significant upward grade migration from the historic to the current WHO grade and from the translation by SEER methodology of the current Gleason score to WHO grade (p <0.0001). Interpretive and chronological bias caused expansion of the moderately differentiated category at the expense of well differentiated cancer and significant deviation in cancer specific survival curves (p <0.013). SEER translation bias resulted in expansion of the moderately differentiated grade category at the expense of poorly differentiated cancer and eliminated the significant difference in cancer specific survival between Gleason 5/6 and 7 (p <0.006). CONCLUSIONS: Contemporary understanding of Gleason grading has lowered the threshold for assignment to higher grade. While a change in tumor biology may be partially responsible for the trend toward higher grade assignment, grade migration as described is also a significant contributing factor in reported histological trends for newly diagnosed prostate cancer and it significantly compromises efforts at historical comparisons.

Acquired bladder diverticula can mimic obstructive extrabiliary jaundice.

A rare case that relates benign prostatic hyperplasia-associated bladder diverticula and obstructive uropathy to extrabiliary obstructive jaundice in an older patient is presented. Immediate decompression of the bladder allowed for prompt restoration of the biliary drainage and normalization of the creatinine within a few days. A hepatobiliary etiology was discarded through prompt radiologic and serologic testing along with computed tomography-guided liver biopsy. Long-term management included open suprapubic prostatectomy and diverticulectomy. This unusual case expands the amount of sound anatomic and pathophysiologic links between urinary and extraurinary manifestations.