Metastatic prostate cancer with normal level of serum prostate-specific antigen

Three-dimensional amide proton transfer-weighted and intravoxel incoherent motion imaging for predicting bone metastasis in patients with prostate cancer: A pilot study

PURPOSE

To explore the value of 3-dimensional amide proton transfer-weighted (APTw) and intravoxel incoherent motion (IVIM) imaging in predicting bone metastasis (BM) of prostate cancer (PCa) in addition to routine diffusion-weighted imaging (DWI).

METHODS

The clinical and imaging data of 39 PCa patients who were pathologically confirmed in our hospital from March 2019 to February 2022 were retrospectively analyzed, and they were divided into BM-negative (27 patients) and BM-positive (12 patients) groups. MR examination included APTw, DWI and IVIM imaging. The IVIM data was fitted by single-exponential IVIM model (IVIM_mono) and double-exponential IVIM model (IVIM_bi), respectively. The APTw, ADC, IVIM_mono (D_mono, D*_mono, and f_mono), and IVIM_bi (D_bi, D*_bi, and f_bi) parameters were independently measured by two radiologists. The synthetic minority oversampling technique (SMOTE) was conducted to balance the minority group. Mann-Whitney U test or Student's t-test was used to compare above values between the BM-negative and BM-positive groups. The diagnostic performance was evaluated with receiver operating characteristic (ROC) analysis of each parameter and their combination. The Delong test was used for ROC curve comparison.The relationship between APTw and IVIM was explored through Spearman's rank correlation analysis.

RESULTS

The APTw and D*_mono values were higher, and the ADC, f_mono, and f_bi values were lower in the BM-positive group than in the BM-negative group (all P < 0.05). Among the individual parameters, the AUC of f_mono was the highest (AUC = 0.865), and AUC (f_mono) was significantly higher than AUC (f_bi), AUC (D*_mono), and AUC (ADC) (all P < 0.05). The AUC (IVIM_mono) was higher than the AUC (IVIM_bi) (P = 0.0068). The combination of APTw and IVIM_mono further improved diagnostic capability, and the AUC of APTw+IVIM_mono was significantly higher than those of APTw and DWI (all P < 0.05). No correlation was found between IVIM-derived parameters and APTw value.

CONCLUSION

Both 3D APTw and IVIM imaging could predict BM of PCa. IVIM showed better performance than APTw and DWI, and the single-exponential IVIM model was superior to the double-exponential IVIM model. The combination of APTw and IVIM could further improve diagnostic performance.

Radioligand Therapy With 177Lu-Prostate-Specific Membrane Antigen in a Patient With Non-Prostate-Specific Antigen-Secreting Metastatic Prostate Cancer

Progression of prostate cancer and prostate-specific antigen (PSA) elevation are closely associated. In fewer than 1% of all cases, disease progression may occur despite low or undetectable PSA levels. In these conditions, androgen deprivation therapy is relatively ineffective, and the prostate cancer progresses very quickly. We present a 65-year-old man with non-PSA-secreting prostate cancer and widespread metastases with rather fair response to Lu-prostate-specific membrane antigen radioligand therapy.

The value of the plasma circulating cell-free DNA concentration and integrity index as a clinical tool for prostate cancer diagnosis: a prospective case-control cohort study in an Iranian population

Introduction: Prostate cancer (PCa) is the most common cancer among men and the second cause of cancer death among men. For early detection and differentiating PCa from benign prostate hyperplasia (BPH) tissue biopsy has been used for decades. However, circulating cell-free DNA (ccfDNA) testing is a noninvasive, fast, easily repeatable, and sensitive liquid biopsy for cancer detection. Hence, we aimed to investigate the value of the ccfDNA concentration and integrity index in peripheral blood of a population of Iranian prostatic patients for early diagnosis of the disease.

Materials and methods: 100 subjects including 30 PCa, 40 BPH, and 30 healthy individuals were selected. ccfDNA was extracted from fresh blood plasma, and its total concentration and the integrity index were estimated by amplification of ALU115 and ALU247 repeat elements using quantitative real-time PCR.

Results: In the PCa group, the ccfDNA concentration and its integrity were significantly higher than that of the BPH and healthy groups (P-value <0.001 and P-value <0.001). The ccfDNA concentration and its integrity were higher in BPH compared to the healthy group, although it was not statistically significant (P-value =0.836 and P-value =0.053, respectively).

Conclusion: A significant relation between ccfDNA concentration, its integrity, and PCa suggests that the liquid biopsy can be used as a noninvasive early diagnostic biomarker. Determination of a cutoff or a diagnostic range value of the measured parameters for healthy, BPH, and PCa subjects in more samples of Iranian population results in timely, correct, and early detection, which results in better treatment outcomes. Moreover, this method may reduce overdiagnosis and overtreatment procedures.

Extensive Metastases in Prostatic Carcinoma with Normal Prostate-Specific Antigen and Raised Carcinoembryonic Antigen – Small Cell Carcinoma of Prostate: A Rare Entity

Small cell carcinoma of prostate is a neuroendocrine tumor of prostate seen in 0.5%–2% of men with carcinoma prostate. Prostate-specific antigen (PSA) is a common tumor marker which is often raised in prostatic carcinoma. However, prostatic carcinoma can progress with normal or low serum PSA levels at the time of diagnosis. Carcinoembryonic antigen (CEA) is a tumor marker of different carcinomas. Small cell carcinoma prostate is a highly aggressive tumor which can progress with normal or low serum PSA levels and raised CEA levels. We report a case of 65-year-old male with enlarged prostate with extra-prostatic spread, hepatic metastases, metastatic retroperitoneal and pelvic lymph nodes, osteoblastic metastasis in lumbar spine with normal serum PSA, and raised CEA levels. Prostatic biopsy was suggestive of small cell carcinoma.

The U Shape of Prostate-specific Antigen and Prostate Cancer-specific Mortality in High-grade Metastatic Prostate Adenocarcinoma

BACKGROUND

Accumulated evidence suggests that metastatic prostate cancer (mPCa) with a low prostate-specific antigen (PSA) level may be a unique entity. However, its clinical features and prognosis have not been fully evaluated.

OBJECTIVE

To investigate the clinical features of low-PSA mPCa and the impact of low PSA level on overall survival (OS) and PCa-specific mortality (PCSM) of mPCa.

DESIGN, SETTING, AND PARTICIPANTS

A total of 8479 mPCa patients were retrieved from the Surveillance, Epidemiology, and End Results program (2010-2015). The median follow-up was 18 mo.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Cox regression and Fine-Gray competing risk were used to calculate the hazard ratio (HR) and subdistribution hazard ratio (sHR) for OS and PCSM, respectively.

RESULTS AND LIMITATIONS

A higher rate of T4 stage disease (19.8%) and visceral metastasis (18.2%) and the shortest median OS (34 mo) were observed in mPCa patients with Gleason 8-10 and PSA ≤4ng/ml. In the Cox regression model, PSA ≤4ng/ml was a significant predictor of OS for Gleason 8-10 disease. The distribution of PCSM by PSA was U-shaped for Gleason score 8-10 (PSA 4.1-10ng/ml as the referent), with an adjusted sHR of 1.52 for PSA ≤4.0ng/ml (95% confidence interval: 1.17-1.96) versus 0.99 for PSA 10.1-20ng/ml and 1.35 for PSA >20ng/ml. In contrast, the distribution of PCSM by PSA was linear for Gleason 5-7. Sensitivity analyses showed similar results in Gleason 9-10 and Gleason 10 subgroup. The study is limited by its retrospective design.

CONCLUSIONS

Low PSA, high-grade mPCa has a higher proportion of T4 stage disease, visceral metastasis, and PCSM.

PATIENT SUMMARY

We found that 2.8% of high-grade metastatic prostate cancer has a prostate-specific antigen level ≤4ng/ml at diagnosis. This population has aggressive clinical features and a poor cancer-specific outcome. Our results highlighted this under-reported population, and the management of these patients warrants further research.

Prostate cancer in a patient with multiple pulmonary metastases alone and respiratory symptoms

An 87-year-old man was admitted complaining of cough after he had been treated with drugs at another hospital. Chest X-ray revealed multiple nodules, and chest computed tomography (CT) showed metastatic lung tumors. Abdominal CT revealed staining of the outer portion of the prostate by contrast medium, though this finding was considered nonspecific and nondiagnostic. A CT-guided biopsy of a lung tumor was performed, and the lung tumor was found to be positive for prostate-specific antigen (PSA). Prostate carcinoma was diagnosed by prostate biopsy, which yielded the same findings as the lung tumor. The serum PSA level was high. No metastases except for pulmonary lesions were observed on a bone scintigram and abdominal CT. Prostate carcinoma with pulmonary metastases alone was therefore diagnosed. The present case represents a rare case of pulmonary metastases without any other metastases.

Progression of prostate cancer despite an extremely low serum level of prostate-specific antigen

A 61-year-old man who had been diagnosed with prostate cancer 9 years ago and had been treated with pelvic irradiation and intermittent androgen deprivation therapy visited the emergency room because of back pain and weakness in both legs. Spine magnetic resonance imaging showed a lumbar epidural mass and spine metastasis. The whole-body workup revealed multiple metastases to the lymph nodes, bone, liver, and lung. The serum prostate-specific antigen was 0.02 ng/ml. He underwent laminectomy, posterior fixation, and epidural mass excision, and metastatic adenocarcinoma from the prostate was diagnosed. The patient underwent 1 cycle of docetaxel-based chemotherapy. More chemotherapy could not be done because of his general weakness. The patient died one month later of multiple organ failure.

Integrated proteomic analysis of human cancer cells and plasma from tumor bearing mice for ovarian cancer biomarker discovery

Background

The complexity of the human plasma proteome represents a substantial challenge for biomarker discovery. Proteomic analysis of genetically engineered mouse models of cancer and isolated cancer cells and cell lines provide alternative methods for identification of potential cancer markers that would be detectable in human blood using sensitive assays. The goal of this work is to evaluate the utility of an integrative strategy using these two approaches for biomarker discovery.

Methodology/Principal Findings

We investigated a strategy that combined quantitative plasma proteomics of an ovarian cancer mouse model with analysis of proteins secreted or shed by human ovarian cancer cells. Of 106 plasma proteins identified with increased levels in tumor bearing mice, 58 were also secreted or shed from ovarian cancer cells. The remainder consisted primarily of host-response proteins. Of 25 proteins identified in the study that were assayed, 8 mostly secreted proteins common to mouse plasma and human cancer cells were significantly upregulated in a set of plasmas from ovarian cancer patients. Five of the eight proteins were confirmed to be upregulated in a second independent set of ovarian cancer plasmas, including in early stage disease.

Conclusions/Significance

Integrated proteomic analysis of cancer mouse models and human cancer cell populations provides an effective approach to identify potential circulating protein biomarkers.

Prostate-specific antigen and prostate cancer: prediction, detection and monitoring

Testing for prostate-specific antigen (PSA) has profoundly affected the diagnosis and treatment of prostate cancer. PSA testing has enabled physicians to detect prostate tumours while they are still small, low-grade and localized. This very ability has, however, created controversy over whether we are now diagnosing and treating insignificant cancers. PSA testing has also transformed the monitoring of treatment response and detection of disease recurrence. Much current research is directed at establishing the most appropriate uses of PSA testing and at developing methods to improve on the conventional PSA test.

Is digital rectal examination still necessary in the early detection of prostate cancer?

BACKGROUND

PSA measurement is important in prostate cancer detection. However, applying cut-off values of >4 ng/ml as indication for biopsy misses 20-30% of tumours.

AIMS

To determine the number of patients with prostate cancer and normal age-related PSA, referred for TRUS biopsy due to abnormal DRE alone.

METHODS

We reviewed patients referred for biopsy over 12 months. Indication for biopsy included abnormal PSA, abnormal DRE, or both.

RESULTS

Four-hundred and sixty-five (465) TRUS biopsies were performed, 209 were positive. Of the 183 (183/209) positive on whom complete data were available, 4 (2.2%) had a normal age-related PSA but an abnormal DRE.

CONCLUSIONS

Metastatic prostate cancer remains incurable. Therefore detection of organ-confined and potentially curable disease, is crucial. Though PSA has led to earlier detection, this study emphasises the importance of clinical examination, illustrating a normal PSA cannot eliminate the possibility of cancer. DRE and PSA should be interpreted as being collaborative, not competitive.

Prostate cancer progression in the presence of undetectable or low serum prostate-specific antigen level

BACKGROUND

The serum prostate-specific antigen (PSA) level after definitive treatment for prostate cancer (PC) is a powerful predictor of outcome. Occasionally, PC progression can occur despite low or undetectable PSA levels. The authors report on the clinical and pathologic characteristics of patients who experienced PC progression with undetectable or low PSA levels.

METHODS

From an electronic database of all patients with PC who were treated at The University of Texas M. D. Anderson Cancer Center between 1999 and 2004, a group of 46 patients was identified who had progression to metastatic PC detected with concomitant PSA levels from 0.1 ng/mL to 2 ng/mL. Patient charts were reviewed for tumor stage, Gleason score, pretreatment PSA level, and the presence of atypical histologic variants (ie, ductal, sarcomatoid, or small cell cancers). The nadir PSA level after treatment and the PSA level at the time metastatic PC was detected were determined. The patients were followed semiannually, and imaging studies were obtained at the discretion of treating physicians. The sites of metastasis and histologic confirmation were reported when available.

RESULTS

Twenty-three of 46 patients underwent radical prostatectomy, 11 patients received radiation therapy, and 12 received hormone treatment as their initial form of therapy. Progression to metastatic disease with concomitant, undetectable PSA levels occurred in 10 patients, including 3 patients who had not received treatment with hormones. The sites of metastasis included bone (n = 35 patients), liver (n = 7 patients), retroperitoneal lymph nodes (n = 5 patients), lungs (n = 4 patients), and brain (n = 1 patient). Aggressive and locally advanced PC were common features in these patients: Eighty-five percent had Gleason scores >or=7, 63% had clinical T3 or T4 tumors, and 41% had pretreatment PSA levels >10 ng/mL. Atypical histologic variants were observed in 21 patients (46%) and in 8 of 10 patients who progressed with undetectable PSA levels. In 10 patients (22%), metastasis were detected in the presence of an undetectable PSA level. Eight of those patients had small cell carcinoma. In 19 patients (41%), progression to metastasis occurred without any increase in their PSA from the nadir level. Thirty-one patients (67%) were asymptomatic at the time metastasis was detected, and the detection of metastasis in these patients occurred only because of routine imaging studies.

CONCLUSIONS

Progression of PC may occur despite undetectable or low PSA levels. Complete physical evaluation and imaging studies may be indicated in the surveillance of patients with high-grade, locally advanced tumors, especially when atypical histologic variants are present.

EGFR signaling pathway negatively regulates PSA expression and secretion via the PI3K-Akt pathway in LNCaP prostate cancer cells

Epidermal growth factor (EGF) and its receptor (EGFR) are involved in hormone-refractory growth and poor prognosis of a subgroup of human prostate cancer. In this communication, we investigated the regulation of PSA by the EGFR signaling pathway using LNCaP C-81 prostate cancer cells. Administration of EGF stimulated the growth of LNCaP C-81 cells, however, PSA expression and secretion were suppressed. An EGFR inhibitor, AG1478, abrogated the PSA suppression effect by EGF, in concurrence with the suppression of tyro-phosphorylation levels of EGFR. Interestingly, the AR level was also decreased in EGF-treated LNCaP C-81 cells. Moreover, LY294002, but not PD98059, inhibited the PSA and AR suppression effect by EGF in concurrence with the suppression of phosphorylation levels of Akt. In conclusion, our results strongly suggest the existence of a novel androgen-independent PSA regulatory mechanism, i.e., the EGFR signaling pathway negatively regulates PSA expression which may be induced by the alteration of AR expression via the PI3K-Akt pathway in LNCaP C-81 cells.