Site-specific relapse patterns of patients with biochemical recurrence following radical prostatectomy assessed by 68Ga-PSMA-11 PET/CT or 11C-Choline PET/CT: impact of postoperative treatments

Elective nodal radiotherapy with a gapless radiation field junction for oligorecurrent prostate cancer after previous radiotherapy

Purpose

To evaluate the feasibility of subsequent elective nodal radiotherapy (ENRT) for nodal recurrences after previous radiotherapy with a defined planning approach for a gapless radiation field junction.

Methods

Patients with 1) previous radiotherapy of prostate or prostatic fossa and subsequent pelvic ENRT or 2) previous pelvic radiotherapy and subsequent ENRT to paraaortic lymph nodes (LN) and gapless junction of both radiation fields were analyzed. The cumulative maximum dose (D_max-cum) and the maximum cumulative dose in 1 cc (D_1cc-cum) were estimated. Absolute toxicity and the toxicity exceeding baseline were evaluated.

Results

Twenty-two patients with PSMA-PET/CT-staged nodal oligorecurrence after prior radiotherapy were treated with pelvic (14 patients) or paraaortic ENRT (9 patients). One patient was treated sequentially at both locations. Median time between first and second RT was 20.2 months. Median doses to the lymphatic pathways and to PET-positive LN were 47.5 Gy and 64.8 Gy, respectively. The planning constraint of an estimated D_max-cum ≤ 95 Gy and of D_1cc-cum < 90 Gy were achieved in 23/23 cases and 22/23 cases, respectively. Median follow-up was 33.5 months. There was no additional acute or late toxicity ≥ grade 3. Worst acute toxicity exceeding baseline was grade 1 in 68.2% and grade 2 in 22.7% of patients. Worst late toxicity exceeding baseline was grade 1 in 31.8% and grade 2 in 18.2% of patients.

Conclusion

ENRT for nodal recurrences after a previous radiotherapy with gapless junction of radiation fields seems to be feasible, applying the dose constraints D_max-cum ≤ 95 Gy and D_1cc-cum < 90 Gy without grade 3 acute or late toxicities exceeding baseline.

Clinical and Biological Significance of DNA Methylation-Driven Differentially Expressed Genes in Biochemical Recurrence After Radical Prostatectomy

Background: Biochemical recurrence (BCR) after radical prostatectomy indicates poor prognosis in patients with prostate cancer (PCA). DNA methylation (DNAm) is a critical factor in tumorigenesis and has attracted attention as a biomarker for the diagnosis, treatment, and prognosis of PCA. However, the predictive value of DNAm-derived differentially expressed genes (DMGs) in PCA with BCR remains elusive.

Methods: We filtered the methylated genes and the differentially expressed genes (DGEs) for more than 1,000 clinical samples from the TCGA cohort using the chAMP and DESeq2 packages of R language, respectively. Next, we integrated the DNAm beta value and gene expression data with the Mithymix package of R language to obtain the DMGs. Then, 1,000 times Cox LASSO regression with 10-fold cross validation was performed to screen signature DMGs and establish a predictive classifier. Univariate and multivariate cox regressive analyses were used to identify the prognostic factors to build a predictive model, and its performance was measured by receiver operating characteristic, calibration curves, and Harrell’s concordance index (C-index). Additionally, a GEO dataset was used to validate the prognostic classifier.

Results: One hundred DMGs were mined using the chAMP and Methymix packages of R language. Of these, seven DMGs (CCK, CD38, CYP27A1, EID3, HABP2, LRRC4, and LY6G6D) were identified to build the prognostic classifier (Classifier) through LASSO analysis. Moreover, univariate and multivariate Cox regression analysis determined that the Classifier and pathological T stage (pathological_T) were independent predictors of BCR (hazard ratio (HR 2.2), (95% CI 1.4–3.5), p < 0.0012, and (HR 1.8), (95% CI 1.0–3.2), p < 0.046). A nomogram based on the Classifier was constructed, with high prediction accuracy for BCR-free survival in TCGA and GEO datasets. GSEA enrichment analysis showed that the DMGs were mainly enriched in the metabolism pathways.

Conclusion: We identified and validated the nomogram of BCR-free survival for PCA patients, which has the potential to guide treatment decisions for patients at differing risks of BCR. Our study deepens the understanding of DMGs in the pathogenesis of PCA.

Radium-223 in patients with prostate specific antigen (PSA) progression and without clinical metastases following maximal local therapy: A pilot study

BACKGROUND

Despite the curative intent of radical prostatectomy (RP) (+/- radiotherapy (RT)), 30% of the clinically localized prostate cancer (CaP) patients will develop rising PSA (prostate specific antigen). In absence of clinical recurrence, there is a lack of effective treatment strategies in order to control the disease at its earliest (micro)metastatic stage. The aim of this study was to assess safety, tolerability, and biochemical response of off-label Radium-223 (Xofigo) treatment in CaP patients with PSA relapse following maximal local therapy.

METHODS

We conducted a prospective, single arm, single center open-label, pilot study with Radium-223 in CaP patients with rising PSA (>0.2 ng/ml) following RP + adjuvant/salvage RT. Negative staging with ⁶⁸Ga-PSMA-11 PET/CT and whole-body MRI was mandatory at time of inclusion. Patients were eligible if they exhibited adverse clinico-pathological features predictive of significant recurrence. Safety, tolerability, biochemical progression (defined as PSA increase >50% from PSA nadir) and clinical recurrence were assessed.

RESULTS

In total, 23 patients were screened of whom 8 patients were included is the study. Radium-223 treatment was safe with no serious treatment related adverse events. One patient developed grade 3 lymphopenia. All patients rapidly developed PSA progression (median PSA progression-free survival: 5.5 months). Eventually all patients experienced clinical recurrence (median clinical recurrence-free survival 11.0 months) of whom only 2 patients developed skeletal recurrence.

CONCLUSIONS

Radium-223 in patients with PSA relapse following maximal local treatment without clinical metastases is safe. However, the clinical benefit of Ra-223 in this setting is doubtful as significant oncological benefit is lacking.

Oligorecurrent prostate cancer treated with metastases-directed therapy or standard of care: a single-center experience

BACKGROUND

The optimal treatment for oligorecurrent prostate cancer (PCa) is a matter of debate. We aimed to assess oncologic outcomes of patients treated with metastasis-directed therapy (MDT) vs. androgen deprivation therapy (ADT) for oligorecurrent PCa.

METHODS

We analyzed data from patients with oligorecurrent PCa treated with ADT (n = 121), salvage lymph node dissection (sLND) (n = 191) or external beam RT (EBRT) (n = 178). Radiological recurrence (RAR) was defined as a positive positron emission tomography imaging after MDT or ADT. Second-line systemic therapies (SST) were defined as any systemic therapy administered for progression. Oncologic outcomes were evaluated separately for patients with node-only or bone metastases. Kaplan-Meier method was used to assess time to RAR, SST, and cancer-specific mortality (CSM). Predictors of RAR, SST, and castration-resistant PCa (CRPCa) were assessed with Cox regression analyses.

RESULTS

Overall, 74 (22.6%), 63 (19.2%), and 191 (58.2%) patients were treated with ADT, EBRT, and sLND for lymph node-only recurrence. Both sLND (HR 0.56, 95% CI 0.33-0.94) and EBRT (HR 0.46, 95% CI 0.25-0.85) were associated with better RAR than ADT. Similarly, sLND (HR 0.25, 95% CI 0.13-0.50) and EBRT (HR 0.41, 95% CI 0.19-0.87) were associated with longer SST, as compared with ADT. Similar results were found for CRPCa status. Oncologic outcomes were similar between sLND and EBRT. MDT was not associated with survival benefit in patients with bone metastases as compared with ADT.

CONCLUSIONS

sLND and EBRT were associated with better RAR, SST, and CRPCa-free survival as compared with ADT in patients with oligometastatic PCa nodal recurrence. No difference in survival outcomes was observed between sLND and EBRT. MDT was not associated with survival benefit in patients with bone metastases, as compared with ADT.