Concomitant intraductal carcinoma of the prostate and response to hormonal therapy in metastatic prostate carcinoma

INTRODUCTION AND OBJECTIVE

Most prostate cancers are classified as acinar adenocarcinoma. Intraductal carcinoma of the prostate (IDC-P) is a distinct histologic entity that is believed to represent retrograde spread of invasive acinar adenocarcinoma into prostatic ducts and acini. We have analyzed the impact of IDC-P in hormonal naïve and castration resistant metastatic prostate cancer patients.

PATIENTS AND METHODS

We retrospectively evaluated 118 metastatic castration resistant prostate cancer (mCRPC) patients who were initially diagnosed with distant metastases from May 2010 to September 2018. Group 1 patients included 81 metastatic PCa patients with acinar adenocarcinoma and Group 2 included 37 metastatic PCa patients with IDC-P.

RESULTS

Mean age at presentation was 76 years (IQR 73.4-78.7) in group 1 and 74 years (68.5-80.6) in group 2. Mean PSA at diagnosis was 619 ng/mL (IQR 85-1113) and 868 ng/mL (IQR 186-1922), respectively. Time to castration resistance was 24.7 months (IQR 16.7-32.7) in group 1 and 10.2 months (IQR 4.2-16.2) in group 2 (P = .007). Time to progression in CPRC patients was: 10.6 months (IQR 5.6-15.6) and at 6.2 months (3.2-9.2), respectively (P = .05). Overall survival was 57.9 months in group 1(CI 95% 56.4-59.5) and 38 months (CI 95% 19.9-48.06) in group 2 (P = .001). In the multivariate analysis, adenocarcinoma subtype was statistically significant P .014, CI 95% (HR 0.058, 0.006-0.56) CONCLUSIONS: IDC-P seems to be a subtype of prostate cancer that is associated with a shorter response to hormonal treatment when compared to acinar adenocarcinoma in metastatic patients. New drugs in CRPC scenario as abiraterone and enzalutamide also obtained less response in IDC-P patients. Once IDC-P is identified, clinicians could extrapolate the relative poor response to hormonal therapy. Consequently, follow-up of these patients in this scenario should be more strict.

Concomitant intraductal carcinoma of the prostate and response to hormonal therapy in metastatic prostate carcinoma

INTRODUCTION AND OBJECTIVE

Most prostate cancers are classified as acinar adenocarcinoma. Intraductal carcinoma of the prostate (IDC-P) is a distinct histologic entity that is believed to represent retrograde spread of invasive acinar adenocarcinoma into prostatic ducts and acini. We have analyzed the impact of IDC-P in hormonal naïve and castration resistant metastatic prostate cancer patients.

PATIENTS AND METHODS

We retrospectively evaluated 118 metastatic castration resistant prostate cancer (mCRPC) patients who were initially diagnosed with distant metastases from May 2010 to September 2018. Group 1 patients included 81 metastatic PCa patients with acinar adenocarcinoma and Group 2 included 37 metastatic PCa patients with IDC-P.

RESULTS

Mean age at presentation was 76 years (IQR 73.4-78.7) in group 1 and 74 years (68.5-80.6) in group 2. Mean PSA at diagnosis was 619 ng/mL (IQR 85-1113) and 868 ng/mL (IQR 186-1922), respectively. Time to castration resistance was 24.7 months (IQR 16.7-32.7) in group 1 and 10.2 months (IQR 4.2-16.2) in group 2 (p = 0.007). Time to progression in CPRC patients was: 10.6 months (IQR 5.6-15.6) and at 6.2 months (3.2-9.2), respectively (p = 0.05). Overall survival was 57.9 months in group 1(CI 95% 56.4-59.5) and 38 months (CI 95% 19.9-48.06) in group 2 (p = 0.001). In the multivariate analysis, adenocarcinoma subtype was statistically significant p 0.014, CI 95% (HR 0.058, 0.006-0.56).

CONCLUSIONS

IDC-P seems to be a subtype of prostate cancer that is associated with a shorter response to hormonal treatment when compared to acinar adenocarcinoma in metastatic patients. New drugs in CRPC scenario as abiraterone and enzalutamide also obtained less response in IDC-P patients. In daily clinical practice it might be interesting to take into account that patients with IDC-P may present shorter responses to first and second line hormonal treatments.