Incidental carcinoma of prostate, Long-term follow-up

Incidental prostate cancer diagnosed following a transurethral resection of the prostate: A national database analysis in England

Objectives:

The aim was to compare prostate cancer and all-cause mortality in patients diagnosed with prostate cancer following a transurethral resection of the prostate (TURP) (incidental prostate cancer, IPC), to men diagnosed with localised non-incidental prostate cancer (NIPC).

Patients and methods:

Men diagnosed with localised prostate cancer between 2000 and 2008 were identified from the English national cancer registry. Their records were linked to the Hospital Episode Statistics (HES) database of hospital admissions in England to identify men who had a TURP. Men were considered to have IPC if prostate cancer was diagnosed less than 60 days after TURP. Mortality rates were calculated using the Kaplan–Meier method. Mortality rate ratios (RR) comparing IPC and NIPC were calculated with multivariable Poisson regression adjusting for age group, co-morbidities, year of diagnosis and radical treatment.

Results:

A total of 192,960 men were included. Of these, 6666 (3.5%) had IPC and 186,294 (96.5%) NIPC. Median follow-up was 4.7 years (0.5–11.0). Ten-year prostate cancer mortality was 17.1% in IPC, 19.0% in NIPC. With adjustment, the prostate cancer-specific mortality in IPC was 30% lower than NIPC (RR 0.70, 95% CI 0.65–0.75, p<0.001), with no difference in all-cause mortality.

Conclusion:

Ten-year prostate cancer mortality in IPC was 17%. Men with IPC had lower prostate cancer-specific mortality than other prostate cancer patients.

Outcome of radical prostatectomy for incidental carcinoma of the prostate

OBJECTIVE To evaluate a contemporary series of patients with incidental prostate cancer detected by transurethral resection of the prostate (TURP) and undergoing radical prostatectomy (RP). PATIENTS AND METHODS Between 1998 and 2004, 1931 patients had TURP for obstructive voiding symptoms and suspected BPH. Incidental prostate cancer was found in 104 (5.4%); 26 of these patients had a RP. The pathological staging and treatment of these patients were reviewed retrospectively and the follow-up results obtained. RESULTS Of the 26 patients who had RP, 17 had T1a and nine had T1b carcinoma of the prostate. After RP, six (35%) in the T1a group had no residual tumour (pT0) and 11 (65%) had pT2 cancer; the respective incidence in those with T1b was two and seven, with no pT3 disease in either group. The preoperative Gleason grading did not correspond well with that after RP; 30% of the patients had upgraded Gleason scores and 42% showed either downgrading or no residual tumour, with 81% having Gleason scores of <7. After a median follow-up of 47 months, one patient is receiving hormonal therapy because of biochemical relapse. Conclusion Subsequent to stringent PSA testing and prostate biopsy when indicated, the rate of incidental prostate cancer is low. Furthermore, substantially many patients will harbour either no residual cancer or tumours with favourable characteristics in their RP specimens. However, there is currently no possibility to reliably predict the absence of aggressive prostate cancer after TURP, and thus safely recommend observation instead of further therapy. Therefore, patients with incidental prostate cancer need to be counselled individually. The decision 'treatment or no treatment' should be determined by the patients' age and life-expectancy, tumour aggressiveness in the TURP specimen and the prostate-specific antigen level after TURP.

How much tissue sampling is required when unsuspected minimal prostate carcinoma is identified on transurethral resection?

CONTEXT

When minimal prostate cancer is detected in the initial transurethral resection of the prostate (TURP) sample, it is uncertain how extensively the remaining tissue should be sampled for accurate grading and staging.

OBJECTIVE

To identify whether additional partial or complete sampling is required to accurately evaluate TURP samples with minimal cancer (stage T1a).

DESIGN

We prospectively examined all TURP samples in our institution during 1 year. All specimens were sampled randomly in 6 cassettes. When minimal cancer was found, we performed additional partial sampling (1 block per 5 g of remaining tissue), followed by complete submission of all remaining tissue. All samples were evaluated separately to identify possible changes in Gleason score and tumor volume. We performed a cost analysis for the additional tissue sampling.

RESULTS

Of 747 TURP samples evaluated on the initial 6 cassettes, 125 (16.7%) contained prostate cancer. Minimal cancer involving less than 5% of sampled tissue was found in the initial submission in 26 (3.5%) patients. Additional partial examination required 3.5 blocks per case (median; range, 1-23), while complete processing required an additional 5.5 blocks per case (median; range, 2-25). Initial Gleason scores and tumor volumes were not changed in any of the studied cases after evaluating the additional partial and complete samples. In our laboratory, we calculated a cost of $4336 per year for the additional sampling of TURPs with minimal cancer ($1681 for partial and $2655 for complete sampling).

CONCLUSIONS

When minimal cancer was found in the first 6 cassettes of transurethral resections, additional partial and complete sampling did not change the initial Gleason scores and tumor volumes.

Predictors of cancer progression in T1a prostate adenocarcinoma

BACKGROUND

The biologic behavior of T1a prostate adenocarcinoma is variable. A critical issue in the management of patients with T1a prostate adenocarcinoma is to distinguish those who will develop cancer progression from those who will not. Predictive factors that identify those at high risk of cancer progression are needed to stratify patients for treatment. In the current study the authors attempted to identify such predictors of cancer progression in a large series of untreated patients with lengthy follow-up.

METHODS

The authors studied 102 patients who were diagnosed with T1a prostate adenocarcinoma (incidental tumor involving < or = 5% of the resected prostatic tissue) at the time they underwent transurethral resection of the prostate (TURP) at the Mayo Clinic between 1960-1970. None of these patients were treated. Patient ages ranged from 48-91 years (mean +/- standard deviation, 69 +/- 7 years). The average weight of the resected prostate tissue was 24 +/- 18 g (range, 3-115 g; median, 18 g). Tumor volume was measured by the grid method. Cox proportional hazards models were used to identify factors associated with cancer progression. Survival curves were estimated using the Kaplan-Meier method.

RESULTS

Five-year and 10-year progression free survival rates were 93% and 87%, respectively. During the mean follow-up of 9.5 +/- 6.8 years (range, 0.3-31 years; median, 9.0 years), 14 patients developed clinical cancer progression, including 5 patients with systemic progression (1 with distant metastases and 4 who died of prostate adenocarcinoma). The interval from diagnosis to clinical cancer progression ranged from 1-23 years (mean, 7.3 years). The amount of resected prostate tissue (TURP weight) was associated with progression (P = 0.04). Patients with a TURP weight > or = 30 g had 100% progression free survival at 10 years compared with a progression free survival rate of 73% in patients with a TURP weight < 12 g. Gleason score, tumor volume, number of chips involved by tumor, number of tumor foci, and the presence of high grade prostatic intraepithelial neoplasia were not significant in predicting cancer progression. There was a trend toward a worse prognosis with the increasing number of chips involved by cancer (P = 0.16). Patients with < 3 chips involved by cancer had a 88% 10-year progression free survival rate compared with 73% in patients with > or = 3 chips involved by cancer.

CONCLUSIONS

The clinical course of T1a prostate adenocarcinoma is variable. If left untreated, a small but significant proportion of patients are at risk for disease progression and death. However, the current study found that patients with a TURP weight > or = 30 g have an excellent prognosis and can be managed conservatively.

Anatomy of the prostate and distribution of early prostate cancer

Many of the difficulties in understanding diseases of the prostate have arisen through poor understanding of the anatomy of the prostate. The recent description of histologically separate zones in the prostate has been an important advance, allowing evaluation of separate cancers arising in the transition and peripheral zones of the prostate. While the majority of cancers sampled at transurethral resection of the prostate (TURP) are of transition zone origin, most of these prostates contain separate cancers in the peripheral zone. The peripheral zone cancers have a higher grade-to-volume ratio and are more frequently associated with histological features of progression (extracapsular extension, seminal vesicle invasion) than transition zone cancers. Furthermore, peripheral zone cancers are frequently associated with prostatic intraepithelial neoplasia, in contrast to transition zone cancers. These findings suggest a greater biological activity for cancers arising in the peripheral zone. The majority of cancers detected by digital rectal examination are of peripheral zone origin. While associated transition zone cancers are less frequently present than in TURP sampled prostates, a similarly high association of peripheral zone cancers with histological indicators of biological activity is seen. DNA ploidy analysis of separate foci in radical prostatectomy specimens confirms a significantly higher rate of non-diploidy in cancers of peripheral zone origin, some of very small volume, which further suggests a greater biological activity compared to transition zone cancers.

Radical prostatectomy for impalpable prostate cancer: the Johns Hopkins experience with tumors found on transurethral resection (stages T1A and T1B) and on needle biopsy (stage T1C)

We review the pathological findings of impalpable prostate cancer detected by transurethral resection (stages T1a and T1b) and needle biopsy (stage T1c). The short-term (4 years) and long-term (8 to 10 years) natural histories of untreated stage T1a prostate cancer are examined, as are options to follow patients expectantly. The findings on radical prostatectomy for stages T1a and T1b disease are reviewed and compared. Of the 64 cases of stage T1a disease 13 (20%) showed substantial tumor, including 7 with more than 1 cc of tumor, 5 with capsular penetration and 1 with a Gleason grade 4 + 5 = 9 tumor. Based on preoperative pathological parameters, one could not predict which cases had minimal versus substantial tumor. In a study from our institution that undertook complete histological examination of 39 radical prostatectomy specimens of stage T1b carcinoma, we found that all prostates contained residual carcinoma, 26% had capsular penetration and 10% had invasion of the seminal vesicles. When comparing morphometrically determined volumes of carcinoma with similar data from 56 patients with stage T2 carcinoma, stage T1b tumors were much more heterogeneous in grade, location and volume than were stage T2 lesions. Unless all 3 variables (grade, volume and location) were known, the final pathological stage of T1b cancers could not be predicted with confidence. Finally, we examined preoperative clinical and pathological parameters in 157 men with clinical stage T1c disease undergoing radical prostatectomy, and correlated these findings with pathological extent of disease in the surgical specimen in an attempt to identify a subset of patients with potentially biologically insignificant tumor who might be followed conservatively. Of the tumors 16% were insignificant (less than 0.2 cc, organ confined and Gleason grade less than 7), 10% were minimal (0.2 to 0.5 cc, organ confined and Gleason grade less than 7), 37% were moderate (more than 0.5 cc or capsular penetration with Gleason sum less than 7) and 37% were advanced (capsular penetration with Gleason sum 7 or more, or positive margins, positive seminal vesicles or positive lymph nodes). These findings are intermediate between those found in clinical stages T1a and T2 disease. The best model predicting insignificant tumor was a prostate specific antigen (PSA) density of less than 0.1 and no adverse pathological finding on needle biopsy or PSA density of 0.1 to 0.15 with less than 3 mm. low to intermediate grade cancer on only 1 needle biopsy core. The positive predictive value of the model was 95% with a negative predictive value of 66%.(ABSTRACT TRUNCATED AT 400 WORDS)

Stage T1A carcinoma of prostate

When presented with a post-TURP patient with pathologically confirmed Stage T1a disease, several points should be considered (Fig. 1). Is the patient's anticipated longevity and quality-of-life likely to be affected by the confirmed diagnosis? From current knowledge, men over the age of seventy or with co-morbid risk factors probably will not be adversely affected, and no treatment is required apart from expectant follow-up with semiannual DRE and serum PSA determinations. The group at risk seems to be the young patient with a Stage T1a tumor who is likely to survive more than ten years after the diagnosis. Data showing progression rates without treatment as high as 16-25 percent at eight to ten years seem to indicate the need for additional therapy. If the patient belongs to this category and is ready to pursue more aggressive treatment, reestablishing the diagnosis might be suggested, as well as an evaluation of the pre- and post-TUR PSA levels. This can be done by TRUS-guided biopsies of the prostate (or repeat TURP, which we regard as less preferable). If residual tumor is not found, we would counsel a "wait and see" approach. If subsequent tissue sampling identifies other than well-differentiated cancer or indicates the likelihood of more extensive cancer than the T1a staging, treatment would be suggested. If the restaging reveals some residual well-differentiated disease that would not alter the initial staging of T1a, the patient should be offered the alternatives of close monitoring, radical prostatectomy, or radiation therapy. Until prognostic factors such as DNA ploidy and nuclear roundness are better studied, we are unable to counsel the patient on the biologic significance/aggressiveness of his Stage T1a disease.

The long-term risk of development of prostate cancer in patients with benign prostatic hyperplasia: correlation with stage A1 disease

Although historical data generally attest to a relatively benign course for stage A1 prostate cancer, at least some recent studies suggest that with prolonged followup patients have a significant risk of disease progression. This study was done with the hypothesis that such disease progression is a function of patient age and close, prolonged followup, and not the mere presence of stage A1 disease. A total of 304 patients who underwent transurethral resection of the prostate for histologically confirmed benign prostatic hyperplasia was reviewed, with a minimum followup of 8 years. Of 269 patients with full followup data 187 (70%) are alive without prostate cancer and 61 (23%) died without development of the disease. A total of 21 patients (7.8%) had clinically apparent prostate cancer at a mean of 7.0 years following transurethral resection, of whom 3 (14%) died of prostate cancer and 1 died of other causes. These data suggest that the risk of progression and death from prostate cancer may not be significantly greater in patients with stage A1 disease than in those reported to have benign disease at transurethral prostatectomy.

Prognosis of localised prostatic cancer managed by "watch and wait" policy

Progression (within 2-7 years) and cancer-specific mortality (within 4-9 years) were examined in 94 patients with localised (T0-T2 NXM0) prostatic cancer. The patients received no initial anti-cancer treatment. A significant difference was found according to the initial T category both in progression (T0 focal 1/13, T0 diffuse 9/53, T1-2 13/28) and in cancer-related death (T0 focal 0/13, T0 diffuse 3/53, T1-2 6/28). Progression (G1 4/48, G2 17/42, G3 2/4) and cancer-related deaths (G1 1/48, G2 7/42, G3 1/4) also showed significant differences according to histological differentiation. No difference could be demonstrated according to age.

Diagnosis, prognosis and management of incidentally found prostate cancer

Incidentally discovered cancer of the prostate may be divided into focal and diffuse disease. The focal tumour tends to be of low grade and low-volume and in the majority of patients runs a clinically benign course. In 10-15% of untreated patients, however, progression occurs by 10 years after diagnosis. At the same stage of follow-up 30-63% of the patients have died of other causes, with no evidence of recurrence. In patients with low-grade focal cancer of the prostate, radical prostatectomy may be curative. An alternative management option is to closely observe these patients. Digital rectal examination, prostatic specific antigen, transrectal prostatic ultrasound and repeated prostatic biopsies can all make contributions to the follow-up of these patients.