Expectant management: an option for localized prostate cancer

The 20-Yr Outcome in Patients with Well- or Moderately Differentiated Clinically Localized Prostate Cancer Diagnosed in the Pre-PSA Era: The Prognostic Value of Tumour Ploidy and Comorbidity

OBJECTIVE

This observational cohort study describes the long-term outcome of patients with clinically localized prostate cancer managed with watchful waiting, the prognostic value of tumour ploidy, and the impact of comorbidity.

METHODS

A total of 119 patients with clinically localized (T1-2) prostate cancer consecutively diagnosed from 1978 to 1982 were prospectively managed by watchful waiting, with treatment given if progression occurred.

RESULTS

Median age was 68 yr. Median observation time was 24 yr+/-6.25 (SD). Of the 112 patients who died, 42 died of prostate cancer. Disease-specific survival rates were 85% (95% CI: 77-93%), 58% (46-70%), and 32% (19-46%) at 10, 15, and 20 yr, respectively. Treatment-free survival rate was 43% (95% CI: 33-54%) at 10 yr. Patients aged 70 yr and over had a statistically significant increased risk of dying from any cause. There was a statistically significant increased risk of dying from prostate cancer for patients with nondiploid tumours.

CONCLUSION

In the present series from the pre-PSA era, watchful waiting yielded a relatively high long-term disease-specific survival rate in patients with well- or moderately differentiated clinically localized prostate cancer, and almost half were not treated 10 yr after diagnosis. Watchful waiting may be an option at least for such patients with a 10- to 15-yr life expectancy. Age of 70 yr or more predicted an increased overall mortality. High comorbidity increased the risk (although not statistically significant) for death from any cause and for death from prostate cancer. Patients with nondiploid tumours were at an increased risk to die from prostate cancer.

The utility of magnetic resonance imaging and spectroscopy for predicting insignificant prostate cancer: an initial analysis

OBJECTIVE

To design new models that combine clinical variables and biopsy data with magnetic resonance imaging (MRI) and MR spectroscopic imaging (MRSI) data, and assess their value in predicting the probability of insignificant prostate cancer.

PATIENTS AND METHODS

In all, 220 patients (cT stage T1c or T2a, prostate-specific antigen level <20 ng/mL, biopsy Gleason score 6) had MRI/MRSI before surgery and met the inclusion criteria for the study. The probability of insignificant cancer was recorded retrospectively and separately for MRI and combined MRI/MRSI on a 0-3 scale (0, definitely insignificant; - 3, definitely significant). Insignificant cancer was defined from surgical pathology as organ-confined cancer of </= 0.5 cm(3) with no poorly differentiated elements. The accuracy of predicting insignificant prostate cancer was assessed using areas under receiver operating characteristic curves (AUCs), for previously reported clinical models and for newly generated MR models combining clinical variables, and biopsy data with MRI data (MRI model) and MRI/MRSI data (MRI/MRSI model).

RESULTS

At pathology, 41% of patients had insignificant cancer; both MRI (AUC 0.803) and MRI/MRSI (AUC 0.854) models incorporating clinical, biopsy and MR data performed significantly better than the basic (AUC 0.574) and more comprehensive medium (AUC 0.726) clinical models. The P values for the differences between the models were: base vs medium model, <0.001; base vs MRI model, <0.001; base vs MRI/MRSI model, <0.001; medium vs MRI model, <0.018; medium vs MRI/MRSI model, <0.001.

CONCLUSIONS

The new MRI and MRI/MRSI models performed better than the clinical models for predicting the probability of insignificant prostate cancer. After appropriate validation, the new MRI and MRI/MRSI models might help in counselling patients who are considering choosing deferred therapy.