Dietary habits and prostate cancer detection: a case–control study

Background

Many studies have suggested that nutritional factors may affect prostate cancer development. The aim of our study was to evaluate the relationship between dietary habits and prostate cancer detection.

Methods

We studied 917 patients who planned to have transrectal ultrasonography–guided prostatic biopsy based on an elevated serum prostate-specific antigen (PSA) level, a rising serum PSA level or an abnormal digital rectal examination. Before receiving the results of their biopsy, all patients answered a self-administered food frequency questionnaire. In combination with pathology data we performed univariable and multivariable logistic regression analyses for the predictors of cancer and its aggressiveness.

Results

Prostate cancer was found in 42% (386/917) of patients. The mean patient age was 64.5 (standard deviation [SD] 8.3) years and the mean serum PSA level for prostate cancer and benign cases, respectively, was 13.4 (SD 28.2) μg/L and 7.3 (SD 4.9) μg/L. Multivariable analysis revealed that a meat diet (e.g., red meat, ham, sausages) was associated with an increased risk of prostate cancer (odds ratio [OR] 2.91, 95% confidence interval [CI] 1.55–4.87, p = 0.027) and a fish diet was associated with less prostate cancer (OR 0.54, 95% CI 0.32–0.89, p = 0.017). Aggressive tumours were defined by Gleason score (≥ 7), serum PSA level (≥ 10 μg/L) and the number of positive cancer cores (≥ 3). None of the tested dietary components were found to be associated with prostate cancer aggressivity.

Conclusion

Fish diets appear to be associated with less risk of prostate cancer detection, and meat diets appear to be associated with a 3-fold increased risk of prostate cancer. These observations add to the growing body of evidence suggesting a relationship between diet and prostate cancer risk.     

Risk factors for sporadic giardiasis: a case-control study in southwestern England

To investigate risk factors for sporadic infection with Giardia lamblia acquired in the United Kingdom, we conducted a matched case-control study in southwest England in 1998 and 1999. Response rates to a postal questionnaire were 84% (232/276) for cases and 69% (574/828) for controls. In multivariable analysis, swallowing water while swimming (p<0.0001, odds ratio [OR] 6.2, 95% confidence intervals [CI] 2.3 to 16.6), recreational fresh water contact (p=0.001, OR 5.5, 95% CI 1.9 to 15.9), drinking treated tap water (p<0.0001, OR 1.3, 95% CI 1.1 to 1.5 for each additional glass per day), and eating lettuce (p?=0.01, OR 2.2, 95% CI 1.2 to 4.3) had positive and independent associations with infection. Although case-control studies are prone to bias and the risk of Giardia infection is minimized by water treatment processes, the possibility that treated tap water is a source of sporadic giardiasis warrants further investigation.     

An analysis of preoperative delays prior to radical cystectomy for bladder cancer in Quebec

Background

The province of Quebec has the highest incidence of urothelial tumours in Canada. Radical cystectomy remains the standard treatment for invasive bladder cancer. We have previously observed that prolonged delays between transurethral resection of bladder tumour (TURBT) and radical cystectomy lead to worse survival in Quebec.

Objective

The aim of our study was to characterize the various periods of delay sustained by bladder cancer patients before radical cystectomy across Quebec and to determine their relation to survival.

Methods

We obtained the billing records for all patients treated with radical cystectomies for bladder cancer across Quebec from 1990 to 2002. Collected information included patient age and sex; dates of family physician (FP) and specialist visits with accompanying diagnoses; dates of cystoscopy, TURBT and CT scanning; surgeon age; surgical volume and dates of death.

Results

We analyzed a total of 25 862 visits for 1633 patients. Median diagnostic delays from FP to specialist, then to cystoscopy, then to TURBT and finally from TURBT to CT were 20, 11, 4 and 14 days, respectively, over the entire study period. Median overall delay from FP visit to radical cystectomy was 93 days. In addition, median FP to radical cystectomy delay progressively increased from 1990 to 2000 from 58 to 120 days (p < 0.01). Multivariate analyses showed that patients with an overall delay of either < 25 or > 84 days had a 2.1 and 1.4 times increased risk of dying, respectively (p ≤ 0.01).

Conclusion

Preoperative delays have been progressively increasing over time. Overall, delays from FP to radical cystectomy of < 25 and > 84 days may translate into worse outcomes. Poor survival in cases with < 25 days delay may be attributed to case selection, with more advanced cases being managed much quicker. Poor survival in cases with delays of > 84 days may be attributed to disease progression while awaiting completion of management.     

Subsequent prostate cancer detection in patients with prostatic intraepithelial neoplasia or atypical small acinar proliferation

Introduction:

To evaluate the predictors of prostate cancer in follow-up of patients diagnosed on initial biopsy with high-grade prostatic intraepithelial neoplasia (HGPIN) or atypical small acinar proliferation (ASAP).

Methods:

We studied 201 patients with HGPIN and 22 patients with ASAP on initial prostatic biopsy who had subsequent prostatic biopsies. The mean time of follow-up was 17.3 months (range 1–62). The mean number of biopsy sessions was 2.5 (range 2–6), and the median number of biopsy cores was 10 (range 6–14).

Results:

On subsequent biopsies, the rate of prostate cancer was 21.9% (44/201) in HGPIN patients. Of these, 32/201 patients (15.9%), 9/66 patients (13.6%) and 3/18 patients (16.6%) were found to have cancer on the first, second and third follow-up biopsy sessions, respectively. In ASAP patients, the cancer detection rate was 13/22 (59.1%), all of whom were found on the first follow-up biopsy. There was a statistically significant difference between the cancer detection rate in ASAP and HGPIN patients (p < 0.001). Multivariate analysis showed that the independent predictors of cancer were the number of cores in the initial biopsy, the number of cores (> 10) in the follow-up biopsy and a prostate specific antigen (PSA) density of ≥ 0.15 (odds ratio 0.77, 3.46 and 2.7,8 respectively; p < 0.04). Conversely, in ASAP patients none of these variables were found to be associated with cancer diagnosis.

Conclusion:

ASAP is a strong predictive factor associated with cancer when compared with HGPIN. The factors predictive of cancer on follow-up biopsy of HGPIN are number of cores on initial biopsy, more than 10 cores in rebiopsy and elevated PSA density. As the cancer detection rate on repeated biopsy of HGPIN patients is the same as that of patients without HGPIN, perhaps the standard of repeat biopsy in all patients with HGPIN should be revisited.Owing to the widespread use of prostate specific antigen (PSA) as a screening tool for prostate cancer associated with increasing use of transrectal ultrasound (TRUS) guided prostate needle biopsy and the increasing number of sampling cores per biopsy, the histological findings of high-grade prostatic intraepithelial neoplasia (HGPIN) and atypical small acinar proliferation (ASAP) has also increased.The detection rate of HGPIN in TRUS-guided needle biopsies performed owing to an elevated PSA level or an abnormal digital rectal examination (DRE), was found to be between 4% and 25% of patients^1–4 and the cancer detection rate on repeated biopsy was reported from 2% to 47% of patients.^1,3,5,6,7 Conversely, the rate of ASAP on initial biopsy was reported to range from 2.4% to 3.7%^3,8,9 the cancer detection rate on repeated biopsy was found to be as high as 52% in isolated ASAP^3,8,10 and 72% in ASAP associated with HGPIN.^3,11The management of patients found to have HGPIN on initial biopsy varies considerably, ranging from immediate rebiopsy to close observation at varying intervals.^12–15 Our aim was to examine our experience with prostatic rebiopsy in patients with HGPIN, ASAP or both.     

Practice patterns and recurrence after partial cystectomy for bladder cancer

Purpose  

Partial cystectomy (PC) remains a viable alternative to radical cystectomy (RC) for management of invasive bladder cancer in approximately 5% of patients. We used a population-based database to examine practice patterns and recurrence after partial cystectomy.     

Role of repeated biopsy of the prostate in predicting disease progression in patients with prostate cancer on active surveillance

BACKGROUND: Active surveillance (AS) with deferred treatment is an established management option for patients with prostate cancer and favorable clinical parameters. The impact of repeat biopsy after diagnosis was examined in a cohort of men with prostate cancer on AS. METHODS: In all, 186 men with prostate cancer with favorable parameters or who refused treatment were conservatively managed by AS. Of these, 92 patients had at least 1 biopsy after diagnosis. Patients were followed every 3 to 6 months with prostate-specific antigen (PSA) and physical examination and were offered rebiopsy annually or if there were any changes on physical examination or in the PSA value. Disease progression while on AS was defined as having > or =1 of the following: > or =cT2b disease, > or =3 positive cores, >50% of cancer in at least 1 core, or a predominant Gleason pattern of 4 in rebiopsies. RESULTS: The median age of the patients at the time of diagnosis was 67 years (range, 49-78 years). The median follow-up was 76 months (range, 20-169 months). Of the 92 patients who underwent repeat biopsies, 42 patients, 25 patients, 13 patients, 10 patients, and 2 patients had 1, 2, 3, 4, and 5 rebiopsies, respectively. A total of 34 patients (36%) demonstrated disease progression on rebiopsy. The first rebiopsy was positive for cancer in 48 patients (52.2%) and negative in 44 patients (47.8%). The 5-year actuarial progression-free probability was 82% for patients with a negative first repeat biopsy compared with 50% for patients with a positive first rebiopsy (P = .02). A PSA doubling time <67 months was associated an increased risk of disease progression on biopsy. CONCLUSIONS: Negative rebiopsy in patients with prostate cancer on AS is associated with low-volume disease. The result of first repeated biopsy appears to have a strong impact on disease progression. Patients with a positive first repeated biopsy should be considered for treatment. An intensive biopsy protocol within the first 2 years is required to identify and treat those patients.