Role of radiotherapy in ductal (endometrioid) carcinoma of the prostate

The therapeutic efficacy of radical prostatectomy and external beam radiation therapy in patients with different pathological patterns of prostate cancer

BACKGROUND

We aim to investigate the prognostic value of different pathological patterns of non-adenocarcinoma prostate cancers (PCa) in radical prostatectomy (RP) and external beam radiation therapy (EBRT).

METHODS

Data of 470,258 localized PCa patients between 2004 and 2016 were collected from the Surveillance, Epidemiology, and End Results database. Propensity score matching was performed to balance the baseline characteristics of patients in different groups. Kaplan-Meier curves and Cox regression were used for survival analysis. Overall survival (OS) and cancer-specific survival (CSS) were set as endpoints.

RESULTS

Totally, 1044 patients with non-adenocarcinoma patterns of PCa were included. Patients with small cell neuroendocrine carcinoma (SCNC) and neuroendocrine differentiation (NED) harbored the worst prognosis in both RP and EBRT among all pathological groups. RP exhibited superior effects to EBRT for this group of cases. Ductal carcinoma (DA) was also related to poorer survival outcomes versus PAC in both local therapies. Yet, for men with DA, both RP and EBRT still improved patients' prognosis against no local therapy (NLT), with RP being the superior modality. Cases harboring mucinous adenocarcinoma (MA) and signet ring cell carcinoma (SRCC) shared comparable clinical outcomes to men with PAC. However, for cases with MA, neither RP nor EBRT was related to better survival outcomes against NLT, while for patients with SRCC, both RP and EBRT prolonged patients' survival with similar effects.

CONCLUSIONS

Our study provided a comprehensive view of the treatment effect of RP and EBRT in non-adenocarcinoma PCa patients. These findings could facilitate clinicians in making therapeutic decision-making for non-adenocarcinoma patients.

Ductal prostate cancer: Clinical features and outcomes from a multicenter retrospective analysis and overview of the current literature

Objective

The aim of the study is to evaluate clinical features and outcomes after different therapeutic strategies for ductal prostate adenocarcinoma (DPC), a rare but aggressive subtype of invasive prostate cancer (PCa) accounting for, in the pure and mixed form, 1% or less and 5% or less, respectively, of all the newly diagnosed PCa.

Materials and methods

Patients with a proven diagnosis of DPC undergoing surgery, radiotherapy, and androgen deprivation therapy, alone or in combination, were considered for this multicenter, retrospective study. The study assessed overall survival (OS), disease-free survival (DFS), and age-related disease-specific survival.

Results

Eighty-one patients met the study inclusion criteria. Pure DPC was found in 29 patients (36%) and mixed ductal-acinar-PCa in 52 patients (64%). After a median follow-up of 63 months (range, 3-206 months), 3- and 5-year OS rates were 84% and 67%, respectively, and 3- and 5-year DFS rates were 54% and 34%, respectively. There were no significant differences in OS or DFS between the pure and mixed DPC groups. Pure DPC was associated with a higher rate of metastatic disease at onset. Patients 74 years or younger had better disease-specific survival (p=0.0019). A subgroup analysis favored radiotherapy as the primary treatment for nonmetastatic, organ-confined DPC (3- and 5-year DFS of 80% and 50%, respectively, compared with 5-year DFS of 35% for surgical patients; p = 0.023).

Conclusions

Our study found DPC to be rarer, more aggressive, more likely to metastasize, and have a worse prognosis than the common acinar variant, especially in its pure form. Multicenter series are encouraged to obtain large data sets, or propensity score matching analyses with patients with conventional PCa are desirable to understand the best therapeutic approach and improve outcomes.

Survival after radical prostatectomy vs. radiation therapy in ductal carcinoma of the prostate

AIM

To compare cancer-specific mortality (CSM) rates between radical prostatectomy (RP) vs. external beam radiotherapy (RT) in patients with ductal carcinoma (DC) of the prostate.

MATERIALS AND METHODS

Within the Surveillance, Epidemiology, and End Results (SEER) database (2004-2016), we identified 369 DC patients, of whom 303 (82%) vs. 66 (18%) were treated with RP vs. RT, respectively. Kaplan-Meier plots and uni- and stepwise multivariate Cox regression models addressed CSM in the unmatched population. After propensity score matching (PSM) and inverse probability of treatment weighting (IPTW), Kaplan-Meier curve and Cox regression models tested the effect of RP vs RT on CSM.

RESULTS

Overall, RT patients were older, harbored higher PSA values, higher clinical T and higher Gleason grade groups. 5-year CSM rates were respectively 4.2 vs. 10% for RP vs. RT (HR 0.40, 95% CI 0.16-0.99, p = 0.048, favoring RP). At step-by-step multivariate Cox regression, after adding possible confounders, the central tendency of the HR for RP vs. RT approached 1. PSM resulted into 124 vs. 53 patients treated respectively with RP vs. RT. After PSM, as well as after IPTW, the protective effect of RP was no longer present (HR 1.16, 95% CI 0.23-5.73, p = 0.9 and 0.97, 95% CI 0.35-2.66, p = 0.9, respectively).

CONCLUSIONS

Although CSM rate of ductal carcinoma RP patients is lower of that of RT patients, this apparent benefit disappears after statistical adjustment for population differences.

Knowing what's growing: Why ductal and intraductal prostate cancer matter

Prostate cancer is a common malignancy, but only some tumors are lethal. Accurately identifying these tumors will improve clinical practice and instruct research. Aggressive cancers often have distinctive pathologies, including intraductal carcinoma of the prostate (IDC-P) and ductal adenocarcinoma. Here, we review the importance of these pathologies because they are often overlooked, especially in genomics and preclinical testing. Pathology, genomics, and patient-derived models show that IDC-P and ductal adenocarcinoma accompany multiple markers of poor prognosis. Consequently, "knowing what is growing" will help translate preclinical research to pinpoint and treat high-risk prostate cancer in the clinic.

Optimizing the diagnosis and management of ductal prostate cancer

Ductal adenocarcinoma (DAC) is the most common variant histological subtype of prostate carcinoma and has an aggressive clinical course. DAC is usually characterized and treated as high-risk prostatic acinar adenocarcinoma (PAC). However, DAC has a different biology to that of acinar disease, which often poses a challenge for both diagnosis and management. DAC can be difficult to identify using conventional diagnostic modalities such as serum PSA levels and multiparametric MRI, and the optimal management for localized DAC is unknown owing to the rarity of the disease. Following definitive therapy for localized disease with radical prostatectomy or radiotherapy, the majority of DACs recur with visceral metastases at low PSA levels. Various systemic therapies that have been shown to be effective in high-risk PAC have limited use in treating DAC. Although current understanding of the biology of DAC is limited, genomic analyses have provided insights into the pathology behind its aggressive behaviour and potential future therapeutic targets.

Ductal Prostate Cancers Demonstrate Poor Outcomes with Conventional Therapies

BACKGROUND

Ductal prostate adenocarcinoma (DAC) is a rare, aggressive, histologic variant of prostate cancer that is treated with conventional therapies, similar to high-risk prostate adenocarcinoma (PAC).

OBJECTIVE

To assess the outcomes of men undergoing definitive therapy for DAC or high-risk PAC and to explore the effects of androgen deprivation therapy (ADT) in improving the outcomes of DAC.

DESIGN, SETTING, AND PARTICIPANTS

A single-center retrospective review of all patients with cT1-4/N0-1 DAC from 2005 to 2018 was performed. Those undergoing radical prostatectomy (RP) or radiotherapy (RTx) for DAC were compared with cohorts of high-risk PAC patients.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Metastasis-free survival (MFS) and overall survival (OS) rates were analyzed using Kaplan-Meier and Cox regression models.

RESULTS AND LIMITATIONS

A total of 228 men with DAC were identified; 163 underwent RP, 34 underwent RTx, and 31 had neoadjuvant therapy prior to RP. In this study, 163 DAC patients and 155 PAC patients undergoing RP were compared. Similarly, 34 DAC patients and 74 PAC patients undergoing RTx were compared. DAC patients undergoing RP or RTx had worse 5-yr MFS (75% vs 95% and 62% vs 93%, respectively, p < 0.001) and 5-yr OS (88% vs 97% and 82% vs 100%, respectively, p < 0.05) compared with PAC patients. In the 76 men who received adjuvant/salvage ADT after RP, DAC also had worse MFS and OS than PAC (p < 0.01). A genomic analysis revealed that 10/11 (91%) DACs treated with ADT had intrinsic upregulation of androgen-resistant pathways. Further, none of the DAC patients (0/15) who received only neoadjuvant ADT prior to RP had any pathologic downgrading. The retrospective nature was a limitation.

CONCLUSIONS

Men undergoing RP or RTx for DAC had worse outcomes than PAC patients, regardless of the treatment modality. Upregulation of several intrinsic resistance pathways in DAC rendered ADT less effective. Further evaluation of the underlying biology of DAC with clinical trials is needed.

PATIENT SUMMARY

This study demonstrated worse outcomes among patients with ductal adenocarcinoma of the prostate than among high-grade prostate adenocarcinoma patients, regardless of the treatment modality.

Impact of treatment modality on overall survival in localized ductal prostate adenocarcinoma: A national cancer database analysis

PURPOSE

Ductal adenocarcinoma is considered a rare histological variant of prostate adenocarcinoma (PCa). Given the rarity of this subtype, optimal treatment strategies for men with nonmetastatic ductal PCa is largely unknown. We aimed to describe the impact of surgery, radiotherapy, systemic therapy, and observation on overall survival (OS) in men with nonmetastatic ductal PCa.

MATERIALS AND METHODS

We selected 1,656 cases of nonmetastatic ductal PCa, diagnosed between 2004 and 2015, within the National Cancer Database. Covariates included age, race, Charlson comorbidity score, clinical T stage, clinical lymph node stage, serum prostate specific antigen (PSA), income, hospital type, insurance status, year of diagnosis, and location of residence. Cox regression analysis tested the impact of treatment (surgery, radiotherapy, systemic therapy, and observation) on OS.

RESULTS

In men with nonmetastatic ductal PCa, median (interquartile range [IQR]) age and PSA were 67 (60-73) years and 6.2 (4.2-10.7) ng/ml, respectively. Advanced local stage (≥cT3a) was most frequently observed in patients initially treated with systemic therapy (34.8%), followed by those treated with radiotherapy (18.1%), surgery (7.1%) and observation (6.4%, P< 0.001). Serum PSA at presentation was highest in the systemic therapy cohort (median 16.0 ng/ml, IQR: 4.9-37.7), followed by the radiotherapy cohort (median 7.2 ng/ml, IQR: 4.1-12.2), observation cohort (median 7.0 ng/ml, IQR: 4.3-13.3) and surgery cohort (median 5.9 ng/ml, IQR: 4.3-9.2, P< 0.001). Multivariable analysis showed that in comparison to men treated surgically, OS was significantly lower for patients receiving radiotherapy (HR 2.2; 95% CI: 1.5-3.2), under observation (HR 4.6; 95% CI: 2.8-7.6) and receiving systemic therapy (HR 5.2; 95% CI: 3.0-9.1) as an initial course of treatment.

CONCLUSIONS

While limited by its retrospective nature, our study shows that starting treatment with surgery is associated with more favorable long-term OS outcomes than radiotherapy, systemic therapy or observation.

The Role of Radiotherapy Among Patients With Prostate Ductal Adenocarcinoma

INTRODUCTION

The aim of this study was to perform a Surveillance, Epidemiology, and End Results (SEER) analysis on the effect of radiotherapy (RT) on survival among patients with prostate ductal adenocarcinoma (DA), a rare variant of prostate cancer.

PATIENTS AND METHODS

Cases of T1 to 4 N0 M0 prostate DA diagnosed between 2004 and 2013 were extracted from SEER. The association between categorical variables and radiation therapy was assessed for statistical significance using the χ² test or Fisher exact test. Difference in continuous variables across the RT groups was assessed for statistical significance using the 2-sample t test or non-parametric test. The distribution of overall survival (OS) and disease-specific survival (DSS) between the RT groups was assessed using the Kaplan-Meier method and the log rank test and after propensity matching. The association between hazards of death (HR) and covariates was examined using Cox proportional hazards model. A 2-sided P-value of .05 was used to determine statistical significance.

RESULTS

A total of 205 patients met inclusion criteria. On univariate analysis, RT was associated with significant improvement in OS and DSS. On multivariate Cox regression, RT significantly decreased risk of death for both OS and DSS (HR, 0.516; 95% confidence interval [CI], 0.273-0.978 and HR, 0.232; 95% CI, 0.082-0.658, respectively). After propensity score matching, RT demonstrated a persistent improvement in both OS and DSS.

CONCLUSIONS

RT decreased risk of death for both OS and DSS in patients with node-negative, nonmetastatic prostate DA on multivariable analysis. RT was also associated with improved OS and DSS after propensity matching.

Non-metastatic ductal adenocarcinoma of the prostate: pattern of care from an uro-oncology multidisciplinary group

PURPOSE

To retrospectively review our 20 year experience of multidisciplinary management of non-metastatic ductal prostate cancer (dPC), a rare but aggressive histological subtype of prostate cancer whose optimal therapeutic approach is still controversial.

METHODS

Histologically confirmed dPC patients undergoing primary, curative treatment [radical prostatectomy (RP), external beam radiotherapy (EBRT), and androgen deprivation therapy (ADT)] were included, and percentage of ductal and acinar pattern within prostate samples were derived. Survival outcomes were assessed using the subdistribution hazard ratio (SHR) and Fine-and-Gray model.

RESULTS

From January 1997 to December 2016, 81 non-metastatic dPC fitted selection criteria. Compared to surgery alone, SHR for progression-free survival and cancer-specific mortality were 2.8 (95% CI 0.6-13.3) and 1.3 (95% CI 0.1-16.2) for exclusive EBRT, 2.7 (95% CI 0.6-13.0) and 6.5 (95% CI 0.6-69.8) for adjuvant EBRT, 4.9 (95% CI 0.7-35.5) and 5.8 (95% CI 0.5-65.6) for salvage EBRT post-prostatectomy recurrence, and 3.2 (95% CI 0.7-14.0) and 3.9 (95% CI 0.3-44.1) for primary ADT (P = 0.558; P = 0.181), respectively. Comparing multimodal treatment and monotherapy confirmed the above trends. Local recurrence more typically occurred in pure dPC patients, mixed histology more frequently produced metastatic spread (29.6% relapse in total, P = 0.026).

CONCLUSION

Albeit some limitations affected the study, our findings support the role of local treatment to achieve better disease control and improve quality of life. Different behavior, with typical local growth in pure dPC, higher distant metastatization in the mixed form, might influence treatment response. Given its poor prognosis, we recommend multidisciplinary management of dPC.

HoxB13 expression in ductal type adenocarcinoma of prostate: clinicopathologic characteristics and its utility as potential diagnostic marker

The histologic criteria and selective biomarkers of prostate ductal type adenocarcinoma (DAC) are relatively unknown compared to that known about acinar type adenocarcinoma (AAC). It is known that genetic alteration in Hox13 gene is associated with carcinogenesis of prostate cancer. In this study, we investigated clinicopathologic characteristics of HoxB13 expression in prostate cancer and compared clinicopathologic profiles of DAC and AAC of prostate. After slide review, some morphological variants of DAC, equivalent to Gleason pattern 3 and 5 of AAC were identified. High level of HoxB13 expression was identified in 46.5% (46 out of 99 cases) and 39.2% (31 out of 79 cases) of cases that belong to the training set and test set, respectively. In the training set, high level of HoxB13 expression was significantly correlated with DAC (P < 0.001), higher Gleason score (P < 0.001), advanced pathologic T stage (P = 0.010), and occurrence of biochemical recurrence (BCR; P < 0.001). The test set confirmed that high level of HoxB13 expression was associated with DAC (P < 0.001), higher Gleason score (P = 0.001), advanced pathologic T stage (P < 0.001), and occurrence of BCR (P < 0.001). Our findings suggest that HoxB13 may be a useful diagnostic marker for detection of DAC and a prognostic marker for prediction of BCR.

Does ductal adenocarcinoma of the prostate (DA) have any prognostic impact on patients with de novo metastatic prostate cancer?

BACKGROUND

The prognostic value of ductal adenocarcinoma of the prostate (DA) in nonmetastatic prostate cancer (PCa) has been identified in many studies. However, it remains unknown whether DA is an adverse prognostic factor in metastatic PCa (mPCa).

METHOD

Data from 634 mPCa patients histopathologically documented with DA or/and acinar adenocarcinoma of the prostate in our center between 2012 and 2018 were retrospectively analyzed. Propensity score matching (PSM) was used to balance the baseline features. Data from the Surveillance, Epidemiology, and End Results (SEER) database were utilized to validate our findings. Castration-resistant PCa-free survival (CFS), overall survival (OS), and cancer-specific survival (CSS) were set as endpoints.

RESULTS

DA was confirmed in 35 of 634 (5.5%) patients. Among the DA-positive patients, 7 of 35 (20%) and 28 of 35 (80%) harbored high (DA ≥ 50%) and low (DA < 50%) DA components, respectively. DA was not associated with poorer median CFS (mCFS) or median OS (mOS) either before PSM (mCFS: 16.9 vs 18.4 month, P = .814; mOS: 42.0 vs 70.1 month, P = .796) or after PSM (mCFS: 16.9 vs 16.9 month, P = .949; mOS: 42.0 vs 79.9 month, P = .960). Likewise, in the SEER data, DA-positive patients (n = 15 153) shared similar median CSS (25.0 vs 28.0 month, P = .206) and OS (26.0 vs 35.0 month, P = .095) with DA-negative patients (n = 70). No prognostic difference was found between patients with high and low DA components.

CONCLUSION

We conducted the first study investigating the prognostic value of DA in de novo mPCa. DA was not associated with adverse clinical outcomes in mPCa patients. These findings are helpful for prognostic evaluation, treatment decision making and counseling in mPCa patients.

Flourodeoxyglucose positron emission tomography scan may be helpful in the case of ductal variant prostate cancer when prostate specific membrane antigen ligand positron emission tomography scan is negative

Gallium-68 prostate specific membrane antigen ligand (Ga-68 PSMA) positron emission tomography/computed tomography (PET/CT) scanning is emerging as a useful imaging modality for the staging of suspected and known recurrent or metastatic prostate cancer and in staging of newly diagnosed higher grade prostate cancer. However, we have observed at our institution that in some cases of the more aggressive ductal variant, Ga-68 PSMA uptake has sometimes been poor compared with prominent 18-flourodeoxyglucose (F-18 FDG) avidity seen in F-18 FDG PET/CT, which would suggest that FDG PET/CT scans are important in staging of ductal pattern prostate cancer.

Diagnostic criteria for ductal adenocarcinoma of the prostate: interobserver variability among 20 expert uropathologists

AIMS

Ductal adenocarcinoma of the prostate (DAC) is clinically important, because its behaviour may differ from that of acinar adenocarcinoma. Our aims were to investigate the interobserver variability of this diagnosis among experts in uropathology and to define diagnostic criteria.

METHODS AND RESULTS

Photomicrographs of 21 carcinomas with ductal features were distributed among 20 genitourinary pathologists from eight countries. DAC was diagnosed by 18 observers (mean 13.2 cases, range 6-19). In 11 (52%) cases, a 2/3 consensus was reached for a diagnosis of DAC, and in five (24%) there was consensus against. In DAC, the respondents reported papillary architecture (86%), stratification of nuclei (82%), high-grade nuclear features (54%), tall columnar epithelium (53%), elongated nuclei (52%), cribriform architecture (40%), and necrosis (7%). The most important diagnostic feature reported for DAC was papillary architecture (59%), whereas nuclear and cellular features were considered to be most important in only 2-11% of cases. The most common differential diagnoses were intraductal prostate cancer (52%), high-grade PIN (37%), and acinar adenocarcinoma (17%). The most common reason for not diagnosing DAC was lack of typical architecture (33%).

CONCLUSIONS

Papillary architecture was the most useful diagnostic feature of DAC, and nuclear and cellular features were considered to be less important.

Ductal adenocarcinoma of the prostate: immunohistochemical findings and clinical significance

INTRODUCTION

To investigate the clinical features, diagnosis, treatment, and prognosis of ductal adenocarcinoma of the prostate.

METHODS

The clinicopathological and immunohistochemical data of seven patients with ductal adenocarcinoma of the prostate were retrospectively analyzed. All patients underwent physical examination, magnetic resonance imaging (MRI), bone scan, cystoscopy, and computed tomography (CT) scan. The level of prostate-specific antigen (PSA) before and after surgery was assessed. Different prostate cancer markers were used for immunohistochemical staining.

RESULTS

The mean age of the seven patients diagnosed with prostatic ductal adenocarcinoma in this study was 76.2 years (range 57-88). Five patients presented with intermittent and painless gross hematuria, one patient with progressive dysuria, and one patient with elevated serum PSA on routine health examination. The level of PSA before surgery ranged from 1.3 to 45.0 ng/mL. Immunohistochemical staining results of the prostatic ductal adenocarcinoma confirmed positivity for PSA, prostatic acid phosphatase, androgen receptor, and alpha-methyacyl co-enzyme A (CoA)-reductase markers. Two of the patients underwent bilateral orchiectomy combined with anti-androgen therapy, three underwent transurethral resection of prostate, one received radical prostatectomy, and one received medical castration therapy. The clinical outcomes of all patients were satisfactory, based on follow-up data. The symptoms of hematuria and dysuria were ameliorated well, and the postoperative PSA level decreased below 4.0 ng/mL. Recurrence or metastasis of disease was not detected on MRI and bone scan.

CONCLUSION

Ductal adenocarcinoma of the prostate is a rare subtype of prostate carcinoma, the diagnosis of which could be based on pathological and immunohistochemical examination. Earlier management promises better prognosis.

Histopathological features of ductal adenocarcinoma of the prostate in 1,051 radical prostatectomy specimens

Ductal adenocarcinoma (DAC) of the prostate is thought to have worse prognosis than prostatic acinar carcinoma (PAC). We aimed to evaluate the prognostic significance of histopathological patterns of DAC. A series of 1,051 radical prostatectomy specimens from Karolinska University Hospital 1998-2005 was reviewed. A ductal component was classified as classical DAC (DACC) if it had columnar, pseudostratified epithelium, elongated nuclei, and papillary, glandular, or cribriform architecture; borderline DAC (DACB) if it lacked elongated nuclei or classical architecture; and prostatic adenocarcinoma with ductal features (PCDF) if stratified high-grade nuclei were found. DACC, DACB, and PCDF were seen in 2.6, 4.0, and 1.6 % of the cases. DAC was usually mixed with PAC and constituted 10-100 % (mean 40 %) of the main tumor. Location was periurethral, peripheral, or both in 69.8, 3.5, and 26.7 %. Necrosis was seen in 31.3 %, stromal invasion of DAC in 52.3 %, and intraductal spread in 91.9 %. In DACC/DACB and PAC, extraprostatic extension was seen in 66.7 and 42.4 % (p < 0.001) and seminal vesicle invasion in 13.0 and 5.0 % (p = 0.0045). DACC, DACB, and PCDF had a hazard ratio for biochemical recurrence of 1.5 (0.7-2.8), 1.4 (0.8-2.6) and 1.2 (0.5-2.7). When PCDF was excluded from DAC, hazard ratio was 1.4 (95 % CI 0.9-2.3, p = 0.12). Location, % DAC, necrosis, stromal invasion, or Gleason score were not predictive of recurrence. This suggests that DACC and DACB are more aggressive than average PAC, while cancers with acinar architecture and pseudostratified high-grade nuclei should not be included in DAC.

[Ductal adenocarcinoma of the prostate: a report of 7 cases]

Ductal adenocarcinoma of the prostate is a rare subtype of prostatic adenocarcinoma, defined by morphological criteria as one that has papillary or cribriform architecture composed of high columnar cells with pseudostratified nuclei. We clinically evaluated 7 cases of ductal adenocarcinoma of the prostate in our hospital. The median age was 69 years old and median initial serum PSA level was 22.8 ng/ml. Two cases presented with dysuria, two with macrohematuria and one with abnormality on chest radiograph. Five cases were diagnosed on prostate biopsy, one on TUR-P and one on radical prostatectomy. Two had pure ductal adenocarcinoma and five had mixed ductal adenocarcinoma. Four had metastatic disease, and were treated by hormonal therapy. Among three with non-metastatic disease, two underwent radical prostatectomy with adjuvant radiotherapy and one underwent external beam radiotherapy with hormonal therapy. Three cases with non-metastatic disease have no biochemical recurrence. Among four with metastatic disease, one underwent chemotherapy of Docetaxel and one had found a new lesion in lung.

Variants and unusual patterns of prostate cancer: clinicopathologic and differential diagnostic considerations

Beyond the typical acinar morphology observed in the majority of prostatic adenocarcinomas, a spectrum of morphologic variants and prostate cancer subtypes exists. These unusual entities may be classified as: (1) cancer morphologies arising by divergent differentiation of prostatic ductal, acinar, or basal cells and associated with unique clinical features and/or therapeutic approaches, and (2) histologies occurring in the context of usual prostatic adenocarcinoma that may result in diagnostic misinterpretation or difficulties in Gleason grade assignment, especially in limited samples. This article details a number of variants, with emphasis on diagnostic criteria, differential diagnoses, and clinical significance.

Metastatic ductal carcinoma of the prostate: a rare variant responding to a common treatment

Ductal carcinoma of the prostate is a rare histologic subtype of prostate carcinoma. It represents 0.4% to 0.8% of all prostate cancers and is associated with a poor prognosis. Given the paucity of cases reported in the literature on ductal prostate carcinoma, little is known about how this cancer responds to cytotoxic chemotherapy. We report the case of a 56-year-old male who presented to our clinic with hemoptysis, cough and hematuria and was found to have metastatic ductal carcinoma of the prostate. He was initiated on docetaxel chemotherapy, which has been previously shown to improve overall survival in patients with metastatic prostate adenocarcinoma, but has never been studied in this less common subtype of prostate cancer. To the best of our knowledge, the following is the first reported case of a patient with metastatic ductal carcinoma of the prostate responding to docetaxel chemotherapy.

Ductal adenocarcinoma of the prostate: clinical features and implications after local therapy

BACKGROUND

Ductal or endometrioid adenocarcinoma of the prostate may be a subtype of prostate cancer that is amenable to aggressive local therapeutic strategies. The authors of this report investigated the clinical outcome of patients who had prostate ductal adenocarcinoma after primary radical prostatectomy or radiotherapy.

METHODS

The clinical features of 108 patients with locally confined or advanced prostate ductal adenocarcinoma who had undergone primary radical prostatectomy (surgical group, n = 76 men) or no surgery (nonsurgical group, n = 32 men) were evaluated retrospectively. Clinical records were reviewed, and Gleason scores, clinical/pathologic stages, and preoperative prostate-specific antigen levels were examined. The clinical features that were assessed included local recurrence, distant metastasis, and progression-free and overall survival after primary therapy.

RESULTS

In the surgical group, patients who had pure ductal prostate cancer survived longer (median, 13.8 years; 95% confidence interval [CI], from 13.8 years to not attained) than patients who had mixed ductal prostate cancer (median, 8.9 years; 95% CI, from 7.1 years to not attained; P = .05). In addition, the median time to local progression was shorter (2.8 years vs 4.9 years) and the median time to distant metastasis was longer (3.9 years vs 2.0 years) for patients who had pure ductal adenocarcinoma than for patients who had mixed ductal adenocarcinoma of the prostate after surgery, respectively.

CONCLUSIONS

The results of this preliminary study suggested that pure ductal prostate adenocarcinoma tends to pursue an indolent clinical course and poses an increased risk for local recurrence. Local control (particularly prostatectomy) may improve the clinical outcome of patients with pure prostate ductal adenocarcinoma. These results need to be confirmed in prospective studies.

[Ductal Adenocarcinoma of the prostate with infiltration of the bladder. Can radical cystectomy and antiandrogen therapy cure the disease?]

Ductal adenocarcinoma of the prostate is a rare entity. The lack of correlation between the prostate-specific antigen value and the tumor stage, as well as early dissemination, are major differences from acinar cancer. Due to a lack of early symptoms, the tumor is often found in an advanced stage. Urinary obstruction and hematuria lead to clinical assessment. The characteristic tumor growth near the seminal colliculus can yield a negative digital rectal examination. Despite a lack of treatment guidelines, authors recommend an aggressive surgical concept. First approaches include radical prostatectomy, transurethral resection, and high-dose radiotherapy. Subsequent androgen deprivation is recommended. We report the case of a 64-year-old man with ductal prostate cancer who underwent radical cystectomy followed by androgen deprivation therapy. This is the first such case reported in both the German and the English literature.

Variants and Unusual Patterns of Prostate Cancer

Beyond the typical acinar morphology observed in most prostatic adenocarcinoma, a spectrum of morphologic variants and prostate cancer subtypes exists. These unusual entities may be further classified into (1) cancer morphologies arising by divergent differentiation of prostatic ductal, acinar, or basal cells and associated with unique clinical features or therapeutic approaches, and (2) histologies occurring in the context of usual prostatic adenocarcinoma that may result in diagnostic misinterpretation or difficulties in Gleason grade assignment, especially in limited samples. This article details several variants, with emphasis on diagnostic criteria, differential diagnoses, and clinical significance.

A case of prostatic adenocarcinoma recurrence presenting as ductal carcinoma of the prostate

BACKGROUND

A 61-year-old man with a history of recurrent prostate cancer presented with obstructive urinary symptoms. He had been diagnosed with locally invasive adenocarcinoma of the prostate 10 years previously and treated with neoadjuvant hormonal and external beam radiation therapies. Because of the patient's rising PSA level, he had been started on goserelin 6 years after this diagnosis and bicalutamide 6 months before the current presentation. The patient presented to the urology clinic with worsening lower urinary tract symptoms consisting of nocturia, urgency, and weak stream.

INVESTIGATIONS

Physical examination revealed a largely normal digital rectal examination, although there was slight asymmetry. The post-void residual urine volume was approximately 200 ml. Laboratory tests showed no evidence of urinary tract infection, but confirmed a rising PSA level despite low serum testosterone levels. Cystoscopic examination revealed hypervascular, large lateral prostatic lobes obstructing the bladder neck. The bladder was normal.

DIAGNOSIS

The patient underwent transurethral resection of the prostate. Soon after the resection started, bilateral papillary tumors arising from the stroma of both prostatic lobes were uncovered. Owing to the diffuse nature of the papillary tumors, complete resection was not possible. Pathologic analysis confirmed the presence of ductal carcinoma of the prostate.

MANAGEMENT

The patient had an uneventful postoperative course and reported improvement of voiding symptoms. Staging with bone scan and CT of the abdomen and pelvis demonstrated multi-focal bony metastasis. The patient was started on docetaxel-based chemotherapy for hormone refractory recurrence of prostate cancer as ductal carcinoma of the prostate. He remains under close surveillance for clinical response and progression of disease.