Adjunctive Surgery Is Often Without Oncological Benefit at Time of Postchemotherapy Retroperitoneal Lymph Node Dissection

PURPOSE

Postchemotherapy retroperitoneal lymph node dissection (PC-RPLND) for advanced nonseminomatous germ cell tumors (GCTs) aims to resect all remaining metastatic tissue. Resection of adjacent visceral or vascular organs is commonly performed for complete resection. Resection of organs harboring only necrosis results in relevant overtreatment. The study aimed to describe the frequency of metastatic involvement of resected organs with teratoma or viable cancer and to analyze perioperative complications and relapse-free survival.

MATERIALS AND METHODS

In a 2-center study, we reviewed a cohort of 1204 patients who underwent PC-RPLND between 2008 and 2021 and identified 242 (20%) cases of adjunctive surgery during PC-RPLND. We analyzed the removed adjacent structures and the pathohistological presence of GCT elements in the resected organs: viable GCT, teratoma, or necrosis/fibrosis. Surgery-associated complications were reported according to the Clavien-Dindo classification.

RESULTS

Viable GCT, teratoma, and necrosis were present in 54 (22%), 94 (39%), and 94 (39%), respectively, of all patients with adjunctive resection of adjacent organs. Vascular resections or reconstructions (n = 112; viable: 23%, teratoma: 41%, necrosis: 36%) were performed most frequently, followed by nephrectomies (n = 77; viable: 29%, teratoma: 39%, necrosis: 33%). Perioperative complications of grade ≥ IIIa occurred in 6.6% of all patients, with no difference between the viable GCT and teratoma/necrosis groups (P = .1). A total of 76 patients have been followed without a relapse for at least 36 months. Median follow-up of the whole cohort was 22 months (quartile 7 and 48). Patients with viable GCT/teratoma in the resected specimens had a significantly increased risk of recurrence by 5 years compared to patients with only necrosis (19% vs 59% vs 81%, P < .001).

CONCLUSIONS

This study shows that 33% to 40% of all resections of adjacent organs do not harbor teratoma or viable GCT. This highlights the need for better patient selection for these complex patients.

Detection of Recurrence through microRNA-371a-3p Serum Levels in a Follow-up of Stage I Testicular Germ Cell Tumors in the DRKS-00019223 Study

PURPOSE

Surveillance of clinical stage I (CSI) testicular germ cell tumors (GCT) is hampered by low sensitivity and specificity of current biomarkers for detecting relapses. This study evaluated if serum levels of microRNA371a-3p (M371 test) can: (i) Accurately detect relapses, (ii) detect relapses earlier than conventional technology, and (iii) if elevated postoperative M371 levels may predict relapse.

EXPERIMENTAL DESIGN

In a multicentric setting, 258 patients with testicular CSI GCT were prospectively followed by surveillance for a median time of 18 months with serial measurements of serum M371 levels, in addition to standard diagnostic techniques. Diagnostic characteristics of M371 for detecting relapses were calculated using ROC curve analysis.

RESULTS

Thirty-nine patients recurred (15.1%), all with elevated M371 levels; eight without relapse had elevations, too. The test revealed the following characteristics: area under the ROC curve of 0.993, sensitivity 100%, specificity 96.3%, positive predictive value 83%, negative predictive value 100%. Earlier relapse detection with the test was found in 28%, with non-significant median time gain to diagnosis. Postoperative M371 levels did not predict future relapse.

CONCLUSIONS

The sensitivity and specificity of the M371 test for detecting relapses in CSI GCTs are much superior to those of conventional diagnostics. However, post-orchiectomy M371 levels are not predictive of relapse, and there is no significant earlier relapse detection with the test. In all, there is clear evidence for the utility of the M371 test for relapse detection suggesting it may soon be ready for implementation into routine follow-up schedules for patients with testicular GCT.

Relapse-free and overall survival in patients with non-seminomatous testicular germ cell tumours with teratoma-free primaries

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Background: Characteristics and outcome of non-seminomatous testicular germ cell tumours (NSGCT) with teratoma-containing primaries are still under debate. Methods: We performed a retrospective analysis including 557 patients with metastatic NSGCT as a registry study within the "German Testicular Cancer Study Group". Results: Of the eligible 557 patients with NSGCT, 237 (42%) of all orchiectomy specimens had teratoma-containing primaries, while 320 (58%) were teratoma-free. Teratoma-containing primaries had a significantly higher clinical stage (p=0.002) and worse prognosis (p=0.051) compared to teratoma-free specimens. Lymph node metastasis were significantly larger before (4.5 vs 2.5cm; p<0.001) and after chemotherapy (3.5 vs 2.5 cm; p<0.001) in teratoma-containing primaries. Post-chemotherapy retroperitoneal lymph node dissection was performed in 57% of all patients. As teratoma-containing specimens revealed a significantly lower number of complete responses after chemotherapy, PC-PRLND was more often performed, with teratomatous elements being more often present in the PC-RPLND specimens compared to non-teratoma containing primaries. Kaplan-Meier estimates revealed that 19% of all patients relapsed during a median follow-up of 56 months [29-112] with a median time to relapse of 10 months. Teratoma-containing had a significantly lower relapse-free survival (RFS) compared to teratoma-free NSGCT (relapse rate 24% vs 16%, p=0.020). 8% (45/533) of all patients died due to their disease. There was no difference regarding the tumour-specific survival between teratoma-containing NSGCT and teratoma-free NSGCT when looking at the entire cohort of patients (8% vs. 9%, p=0.563), however median overall survival was not reached. Conclusions: In our study, NSGCT patients with teratoma-containing primaries showed a significantly higher clinical stage and worse prognosis at time of presentation compared to teratoma-free primaries. Furthermore, patients with teratoma-containing primaries showed a significantly worse relapse-free survival. Consequently, treating physicians should be aware of these patients portending a dismal prognosis and the presence of teratomatous elements might act as a reliable stratification tool for treatment decision in TGCT patients.

Combining PSA and PET features to select candidates for salvage lymph node dissection in recurrent prostate cancer

Objective

To evaluate the relationship between pre-operative PSA value, ⁶⁸Ga-prostate-specific-membrane-antigen (PSMA) PET performance and oncologic outcomes after salvage lymph node dissection (sLND) for biochemical recurrent prostate cancer (PCa).

Patients and methods

The study included 164 patients diagnosed with ≤2 pelvic lymph-node recurrence(s) of PCa documented on ⁶⁸Ga-PSMA PET scan and treated with pelvic ± retroperitoneal sLND at 11 high-volume centres between 2012 and 2019. Pathologic findings were correlated to PSA values at time of sLND, categorized in early (<0.5 ng/ml), low (0.5-0.99 ng/ml), moderate (1-1.5 ng/ml) and high (>1.5 ng/ml). Clinical recurrence (CR)-free survival after sLND was calculated using multivariable analyses and plotted over pre-operative PSA value.

Results

Median [interquartile range (IQR)] PSA at sLND was 1.1 (0.6, 2.0) ng/ml, and 131 (80%) patients had one positive spot at PET scan. All patients received pelvic sLND, whereas 91 (55%) men received also retroperitoneal dissection. Median (IQR) number of node removed was 15 (6, 28). The rate of positive pathology increased as a function of pre-operative PSA value, with highest rates for patients with pre-operative PSA > 1.5 ng/ml (pelvic-only sLNDs: 84%; pelvic + retroperitoneal sLNDs: 90%). After sLND, PSA ≤ 0.3 ng/ml was detected in 67 (41%) men. On multivariable analyses, pre-operative PSA was associated with PSA response (p < 0.0001). There were 51 CRs after sLND. After adjusting for confounders, we found a significant, non-linear relationship between PSA level at sLND and the 12-month CR-free survival (p < 0.0001), with the highest probability of freedom from CR for patients who received sLND at PSA level ≥1 ng/ml.

Conclusions

In case of PET-detected nodal recurrences amenable to sLND, salvage surgery was associated with the highest short-term oncologic outcomes when performed in men with PSA ≥ 1 ng/ml. Awaiting confirmatory data from prospective trials, these findings may help physicians to optimize the timing for ⁶⁸Ga-PSMA PET in biochemical recurrent PCa.

Need for organ preservation in postchemotherapy retroperitoneal lymph node dissection (PC-RPLND)

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Background: The aim ofPC-RPLND for advanced nonseminomatous germ cell tumors is to resect all remaining metastatic tissue. So far, the resection of adjacent visceral or vascular organs is also commonly performed to achieve complete resection of the residual mass. To determine the possibility of more organ preservation, we aimed to analyze the pathohistology of patients with adjunctive surgery as the frequency of metastatic involvement in those organs with teratoma or vital cancer is currently unknown. Methods: We reviewed a cohort of 1204 patients who underwent PC-RPLND between 2008 and 2021 as a 2-center study and identified 242 (20.1%) cases of adjunctive surgery during PC-RPLND. We analysed the pathohistological presence of germ cell tumor elements in the resected organs: viable tumor (V), teratoma (T) or necrosis / fibrosis (N). Surgery associated complications were reported according to the Clavien-Dindo classification. Outcomes of subgroups were compared by using log-rank test. Results: V, T and N were present in 54 (22%), 94 (39%) and 94 (39%) of all patients with adjunct resected organs. In 242 patients, 325 adjunct organs were resected with 66 (27.3%) of these patients receiving a resection of multiple organs. The kidney was the most often resected organ (n = 77; V: 29% T: 39% N: 32%), followed by V. Cava (n = 67; V: 25% T: 36%, N: 39%) and partial liver resections (n = 50; V: 16%, T: 30%, N: 54%). Postoperative complications occurred in 30% of which 22% were Clavien grade III-V, showing no significant differences between V, T and N; p = 0.093. 27% of all patients suffered from a relapse during a median follow-up of 22 months [0-180]. Patients with T or V in the resected specimens had a significantly reduced 5-year RFS compared to patients with only N (39%, 81%, p < 0.001). Conclusions: This study shows tremendous need for more organ preservation as 40% of all resections of adjunct organs are oncologically unnecessary due to the presence of N only in the pathological specimens. Therefore, in case of doubt, we should increase intraoperative frozen section to avoid oncologically unnecessary adjunctive surgeries, especially nephrectomies and vascular resections. Additionally, serological or image-based means for a more accurate presurgical workup are required to spare patients with N from PC-RPLND in general.

Single-course bleomycin, etoposide, and cisplatin (1xBEP) as adjuvant treatment in testicular nonseminoma clinical stage 1: outcome, safety, and risk factors for relapse in a population-based study

Introduction:

Clinical stage 1 (CS1) nonseminomatous (NS) germ cell tumors involve a 30% probability of relapse upon surveillance. Adjuvant chemotherapy with one course of bleomycin, etoposide, and cisplatin (1xBEP) can reduce this risk to <5%. However, 1xBEP results are based solely on five controlled trials from high-volume centers. We analyzed the outcome in a real-life population.

Patients and Methods:

In a multicentric international study, 423 NS CS1 patients receiving 1xBEP were retrospectively evaluated. Median follow-up was 37 (range, 6–89) months. Primary end points were relapse-free and overall survival evaluated after 5 years. We also looked at associations of relapse with clinico-pathological factors using stratified Kaplan–Meier methods and Cox regression models. Treatment modality and outcome of recurrences were analyzed descriptively.

Results:

The 5-year relapse-free survival rate was 96.2%. Thirteen patients (3.1%; 95% confidence interval, 1.65–5.04%) relapsed after a median time of 13 months, of which 10 were salvaged (77%). Relapses were mostly confined to retroperitoneal nodes. Three patients succumbed, two to disease progression and one to toxicity of chemotherapy. Pathological stage >pT2 was significantly associated with relapse rate.

Conclusion:

The relapse rate of 3.1% found in this population of NS CS1 patients treated with 1xBEP at the routine care level was not inferior to the median rate of 2.3% reported from a meta-analysis of controlled trials. Also, the cure rate of relapses of 77% is consistent with the previously reported rate of 80%. This study clearly shows that the 1xBEP regimen represents a safe treatment for NS CS1 patients.

The PRIMETEST trial: Prospective phase II trial of primary retroperitoneal lymph node dissection (RPLND) in stage II A/B patients with seminoma

420

Background: Primary retroperitoneal lymph node dissection (RPLND) in patients (pts) with stage II A/B seminoma without adjuvant local or systemic treatment is an experimental treatment to avoid radio- or chemotherapy–related toxicity. The prospective PRIMETEST trial (NCT 2015053664) evaluates recurrence-free (RFS) and overall survival (OS) as well as surgical safety of patients with clinical stage II A/B seminoma undergoing RPLND without adjuvant treatment. Interim results had been presented at ASCO GU 2019. Methods: Primary endpoint of the study is PFS after a median follow-up of 36 months. We performed unilateral open or robotic RPLND in pts with unilateral retroperitoneal lymphnode metastases < 5 cm (stage IIA and IIB) with human chorionic gonadotropin (HCG) < 5 mU/ml. Pts were included with either stage IIA/B at initial diagnosis, at time of recurrence under active surveillance, or after adjuvant carboplatin in clinical stage I. The phase II trial was designed to exclude the upper limit of a 95% confidence interval at 30% recurrences. Results: Trial accrual was completed in a single center from May 2016 to June 2021 with 33 consecutive pts. 13 and 20 pts presented with stage IIA and IIB, respectively. 9 pts had initial stage II, 19 pts presented with recurrence during active surveillance, 5 pts had adjuvant carboplatin. At time of RPLND median HCG was 0.1 mU/ml (range 0 – 2.2 mU/ml). Open and robotic RPLND was performed in 14 (42 %) and 19 (58 %) pts, respectively. One patient had to be converted from robotic to open surgery. Median size of metastasis on histological report was 28 mm (range 11 – 69 mm) with a median OR time of 169 min (range 101 – 351 min). Median estimated blood loss was 50 ml (range 0 – 400 ml). Higher grade complications (Clavien Dindo ≥ III) occurred in 3/ 33 pts (9 %; 2 x pulmonary embolism, 1 x ureteral stricture requiring ileal ureter substitute). Of 33 pts, 2 pts withdrew their consent during follow-up. As of September 1, 2021, the median follow-up is 26 months (range 2 – 56 months). Up to now we observed 10 recurrences (31 %). RFS is 69 % with a median time from RPLND to relapse of 6 months (range 3 – 36 months). The recurrences included infield recurrences in 3/ 10 cases. 5 and 5 recurrences were observed in stage II A and B pts, respectively. Analysis of predictive factors showed vascular invasion present in 5/ 10 recurrences. Half of pts with relapse were treated with robotic RPLND and open RPLND, respectively. All pts with relapse underwent standard chemotherapy and are currently without evidence of disease. Conclusions: Open and minimally invasive surgical resection of small volume, unilateral seminoma metastasis is feasible with acceptable toxicity. Current recurrence-free survival rates suggest this approach as an option to avoid standard treatment (chemotherapy, radiotherapy) in selected patients. Clinical trial information: NCT2015053664.

Preoperative clinical and radiographic predictors of major vascular surgery in patients with testicular cancer undergoing post-chemotherapy residual tumor resection (PC-RPLND)

PURPOSE

To evaluate the probability to correctly predict major vascular surgery (MVS) in patients undergoing postchemotherapy retroperitoneal lymph node dissection (PC-RPLND) for testicular cancer.

METHODS

From a database of 504 RPLNDs performed in 434 patients (2008-2018), 78 patients submitted to PC-RPLND for non-seminoma germ-cell cancer after cisplatin-based chemotherapy with available preoperative CT scans were identified. Second PC-PLNDs (Re-Dos), salvage RPLNDs, or RPLNDs for late-relapse were excluded as well as thoraco-abdominal approaches. Preoperative imaging was reviewed by a urologist and a radiologist blinded to operative details.

RESULTS

Of 78 patients, 16 (20.5%) underwent MVS (caval and/or aortic replacement or reconstruction). On univariable analyses, transversal diameter, sagittal diameter, tumor volume, aorta- and cava-tumor contact angle, poor IGCCCG score, clinical stage III and preoperative positive markers were predictors of MVS (all p values ≤ 0.01). At multivariable analyses aorta- (cut-off 64°) and cava-tumor contact angle (cut-off 98°) and poor IGCCCG score represented the three most important predictors of MVS (all p values ≤ 0.05). The model constructed has a PPV 100%, NPV 87% and an accuracy of 88%.

CONCLUSIONS

Presence of aorta-tumor contact angle ≥ 64°, cava-tumor contact angle ≥ 98° and poor IGCCCG score identify correctly 9 out of 10 patients requiring MVS at the time of first PC-RPLND.

Late relapsing germ cell tumors with elevated tumor markers

Purpose

Late relapsing germ cell tumors (LR-GCT) are considered a rare distinct biologic entity as their clinical presentation and response to treatment is different to early recurrences. While serum tumor markers (AFP and ß-HCG) play an important role at the time of first diagnosis to correctly classify prognosis and treatment of germ cell tumors, they may not have the same significance in a late relapse situation.

Patients and methods

Thirty-seven patients with LR-GCT with elevated serum tumor markers were identified in our database. Twenty-six patients underwent primary surgical resection of the late relapsing tumor. Eleven patients received salvage chemotherapy and a post-chemotherapy residual tumor resection. Serum tumor markers, histological findings and oncological outcome were analyzed.

Results

In the histopathological specimen, viable cancer was found in 20 cases (54%) and teratoma was found in 16 cases (43%). In nine cases (24%), a somatic-type malignant transformation was present. In 19 of 37 patients (51.4%), the late relapse specimen presented a histological type of GCT, which was not present in the primary histology. Twenty-two patients (59.5%) were included in follow-up analysis. Mean and median follow-up time was 62.2 and 53 months, respectively. Seventeen patients (77.3%) suffered a relapse or had progressive disease after LR therapy. Five patients (22.7%) have been relapse-free after LR therapy (mean FU 61.6 months). Ten patients died of disease during follow-up (45.5%) and had a mean time from LR to death of 66.4 months. Eleven patients were alive at last follow-up (mean FU 62.2 months). Relapse and survival rate were similar between patients who received primary resection of LR tumor and patients who received salvage chemotherapy followed by surgery.

Conclusion

Patients with a late relapsing germ cell tumor and elevated markers have a poor prognosis and a high risk for another relapse independent on primary treatment. The histological type and aggressiveness of a late relapsing tumor cannot be predicted with serum tumor marker levels at the time of diagnosis of LR. In up to 54% of cases, primary histology did not coincide with LR histology. Therefore, we propose primary surgical resection of a late relapsing tumor if a complete resection is feasible in order to gain exact histology and tailor further treatment.

Definition and Impact on Oncologic Outcomes of Persistently Elevated Prostate-specific Antigen After Salvage Lymph Node Dissection for Node-only Recurrent Prostate Cancer After Radical Prostatectomy: Clinical Implications for Multimodal Therapy

BACKGROUND

The optimal definition and prognostic significance of persistently elevated prostate-specific antigen (PSA) after salvage lymph node dissection (sLND) for node-only recurrent prostate cancer (PCa) remain unknown.

OBJECTIVE

To assess the definition and clinical implications of persistently elevated PSA after sLND for node-only recurrent PCa after radical prostatectomy.

DESIGN, SETTING, AND PARTICIPANTS

The study included 579 patients treated with sLND at 11 high-volume centers between 2000 and 2016.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We assessed the linear relationship between the first PSA after sLND and death from PCa. Different definitions of PSA persistence were included in a multivariable model predicting cancer-specific mortality (CSM) after surgery to identify the best cutoff value. We investigated the association between PSA persistence and oncologic outcomes using multivariable regression models. Moreover, the effect of early androgen deprivation therapy (ADT) after sLND was tested according to PSA persistence status and estimated risk of CSM.

RESULTS AND LIMITATIONS

We found an inverse relationship between the first PSA after sLND and the probability of cancer-specific survival. PSA persistence defined as first postoperative PSA ≥0.3 ng/ml provided the best discrimination accuracy (C index 0.757). According to this cutoff, 331 patients (57%) experienced PSA persistence. The median follow-up for survivors was 48 mo (interquartile range 27-74). After adjusting for confounders, men with persistently elevated PSA had higher risk of clinical recurrence (hazard ratio [HR] 1.61), overall mortality (HR 2.20), and CSM (HR 2.59; all p < 0.001) after sLND. Early ADT administration after sLND improved survival only for patients with PSA persistence after surgery (HR 0.49; p = 0.024). Similarly, when PSA persistence status was included in multivariable models accounting for pathologic features, early ADT use after sLND was beneficial only for patients with a predicted risk of CSM at 5 yr of >10%.

CONCLUSIONS

PSA persistence after sLND independently predicts adverse prognosis, with the best discrimination accuracy for CSM provided by a definition of PSA ≥ 0.3 ng/ml. We showed that when stratifying patients by final pathology results and PSA persistence status, early ADT use after sLND was beneficial only for patients with PSA persistence or with a calculated 5-yr risk of CSM of >10%, which could be useful as we await results from ongoing prospective trials.

PATIENT SUMMARY

We found that for patients with prostate cancer who had lymph nodes removed after their cancer recurred, persistently elevated prostate-specific antigen (PSA) levels predict poorer prognosis. We showed that a PSA level of ≥0.3 ng/ml provides the best accuracy in identifying patients with worse prognosis. This may help to improve risk stratification after lymph node removal and allow physicians to optimize treatment strategies after surgery.

Treatment of clinical stage I non-seminoma

Germ cell cancers are the most common solid tumors among men between 15 and 40 years. Non-seminomatous germ cell tumors (NSGCTs) represent a unique and exclusive cohort of germ cell tumor patients. Non-seminoma can harbor different histologic components. The most commonly found histologies are embryonal cell cancer, teratoma, yolk sack tumor and choriocarcinoma, as well as teratocarcinoma and seminoma, in combination with non-seminomatous germ cell tumors histologic types. The clinical definition of stage I non-seminoma is the absence of metastatic lesions on imaging and normal tumor markers. The cure rate for clinical stage I NSGCT is 99% and this can be achieved by three therapeutic strategies: Active surveillance with treatment at the time of relapse, retroperitoneal lymph node dissection or adjuvant chemotherapy. The balancing of these various strategies should always be based on an individual risk profile of NGSCG patient depending on the lymphovascular invasion of the tumor.

Reasons for missing clinically significant prostate cancer by targeted magnetic resonance imaging/ultrasound fusion-guided biopsy

OBJECTIVES

This study evaluates cases with clinically significant prostate cancer (csPCa) missed by targeted biopsy (TB) and analyzes the diagnostic impact of an additional systematic biopsy (SB) in a large patient collective.

METHODS

Consecutive patients with a 3 T multiparametric prostate MRI (mpMRI) and a subsequent MRI/US fusion-guided TB plus 12-core US-guided SB from 01/2014 to 04/2019 were included in this study. Primary study endpoint was the analysis of cases with a csPCa missed by TB and detected by SB. Secondary study objectives were the PCa detection and the correlation with clinical and MRI parameters.

RESULTS

In total 785 patients met the inclusion criteria. 342 patients had a csPCa (median PSAD 0.29 ng/mL/cm³). In 42 patients (13 %), a csPCa was detected only by SB. In 36 of these cases, the localization of the positive SB cores matched with the cancer suspicious region described on mpMRI (mCSR). Cases with a csPCA missed by TB showed either an insufficient MRI segmentation (prostate boundary correlation) (31 %) and/or insufficient lesion registration (lesion transfer, tracking, and/or matching) (48 %), a missed small lesion (14 %), or a failed center of a large lesion (10 %). Median PSAD of patients with non-significant PCa detected by SB was 0.15 ng/mL/cm³.

CONCLUSIONS

Main reasons for missing a csPCa by TB were insufficient prostate segmentation or imprecise lesion registration within MRI/US fusion-guided biopsy. Consequently, verification of MRI quality, exact mCSR assessment, and advanced biopsy experience may improve accuracy. Altogether, an additional SB adds limited clinical benefit in men with PSAD ≤ 0.15 ng/mL/cm³.

PSMA PET/CT vs. CT alone in newly diagnosed biochemical recurrence of prostate cancer after radical prostatectomy: Comparison of detection rates and therapeutic implications

OBJECTIVES

To compare prostate specific membrane antigen (PSMA) Positron Emission Tomography/Computed Tomography (PET/CT) and computed tomography (CT) alone for the detection of biochemical recurrence of prostate cancer (PCa) and effect on treatment.

METHODS

This retrospective study included 59 patients with recently recorded biochemical recurrence of PCa (mean PSA 1.96 ± 1.64 ng/mL) after radical prostatectomy. Patients received PET/CT with either ⁶⁸Ga-PSMA-11 (n = 36) or ¹⁸F-PSMA-1007 (n = 23). PET/CT and CT images were evaluated separately in regard to PCa lesion count, type, and localisation by two physicians. Histopathology, follow-up imaging and PSA levels after salvage irradiation served as reference standard. A McNemar test was used to compare detection rates. Changes in therapeutic approaches based on staging differences between CT alone and PET/CT were assessed in a virtual multidisciplinary tumour board.

RESULTS

There were 142 lesions in 50 of 59 patients. PSMA PET/CT detected 141 lesions (99.3 %) in 50 patients (84.7 %), while CT detected 72 lesions (50.7 %) in 29 patients (49.2 %). A significantly higher detection rate of PSMA PET/CT was observed on a lesion-based analysis (p < 0.0001) and on a patient based analysis (p < 0.0001). Herein, both ⁶⁸Ga- and ¹⁸F-PSMA PET/CT performed significantly better than CT alone (p < 0.0001, respectively). In 9 patients (15.3 %) no relapse was detectable by either modality. All lesions detected by CT were also detected by PSMA PET/CT. In 38 patients PSMA PET/CT detected more lesions than CT alone, altering the treatment approach in 22 of these patients.

CONCLUSION

PSMA PET/CT is superior to CT alone in detecting biochemical recurrence in PCa patients after radical prostatectomy and offered additional therapeutic options in a substantial number of patients.

[Retroperitoneal lymph node dissection in testicular germ cell tumours: indications, complications and special cases]

Die retroperitoneale Lymphadenektomie ist integraler Bestandteil der stadienadaptierten Therapie von testikulären Keimzelltumoren. Verschiedene Ansätze der retroperitonealen Lymphadenektomie werden auf Basis unterschiedlicher Indikationen durchgeführt.

Die nervschonende retroperitoneale Lymphadenektomie als primäre Therapieoption bei nicht seminomatösen Keimzelltumoren im klinischen Stadium I sollte risikoadaptiert erfolgen. Geringfügige perioperative Komplikationen wie Wundinfekte, Lymphozelen und paralytischer Ileus treten bei in etwa 14 % der Patienten auf. Schwerwiegendere Komplikationen wie chylärer Aszites und Lungenarterienembolien treten bei ca. 5,4 % der Patienten auf. Die häufigste Langzeitkomplikation ist hierbei das Auftreten einer Retrograden Ejakulation. Der Erhalt der antegraden Ejakulation kann jedoch bei weit über 90 % der Patienten erreicht werden.

Die postchemotherapeutische retroperitoneale Lymphadenektomie ist integraler Bestandteil der multimodalen Therapie bei retroperitonealen Residualbefunden. Bei residuellen Befunden > 3 cm beim fortgeschrittenen Seminom dient das FDG PET als zuverlässige Entscheidungshilfe zur Durchführung einer retroperitonealen Lymphadenektomie.

Bei ca. 30 % der Patienten mit nicht seminomatösen Keimzelltumoren finden sich residuelle retroperitoneale Tumorbefunde. Diese sollten unabhängig von der Größe der Befunde bei negativen Serumtumormarkern oder Serumtumormarkern im Plateau komplett reseziert werden. Die postchemotherapeutische retroperitoneale Lymphadenektomie stellt einen herausfordernden Eingriff dar und sollte primär an ausgewiesenen Zentren durchgeführt werden. Bei bis zu 25 % der Patienten ist im Rahmen der postchemotherapeutischen retroperitonealen Lymphadenektomie die Resektion umgebender Strukturen indiziert. Eine Beteiligung der aorta abdominalis liegt in 6 – 10 % der Fälle vor, eine Beteiligung der vena cava in ca. 2 % der Fälle. Komplikationsraten liegen bei der postchemotherapeutischen retroperitonealen Lymphadenektomie höher als bei der primären nervschonenenden Lymphadenektomie mit signifikant höherem intraoperativen Blutverlust und signifikant höherer Transfusionsrate. Mit einer Wahrscheinlichkeit von 2 – 7 % tritt chylärer Aszites nach postchemotherapeutischer retroperitonealer Lymphadenektomie häufiger auf. Jedoch kann auch im Rahmen der postchemotherapeutischen Lymphadenektomie bei bis zu 85 % der Erhalt der antegraden Ejakulation erreicht werden. Entscheidend für den Erhalt der antegraden Ejakulation und einer Verbesserung der Morbidität insgesamt ist auch hier das nach Möglichkeit das Anstreben eines nervsparenden Vorgehens durch Anpassung der Felder.

[Systemic therapy for metastatic urothelial carcinoma - Current status and what comes after checkpoint inhibitors?]

The increasing knowledge of the influence of the immune system on tumour development and progression has fundamentally changed our understanding of tumour biology in recent years. While the available treatment options for patients with metastatic urothelial carcinoma of the urinary bladder have hardly improved over decades, the advent of immune checkpoint inhibitors has caused major changes in the corresponding treatment landscape.Although cisplatin-based combination therapies remain the main element, additional effective treatment options now exist with the PD-(L)-1 inhibitors atezolizumab, pembrolizumab and nivolumab, which have been approved in Europe. A remarkable long-term response is balanced by the occurrence of occasionally severe immune-mediated side effects and an overall low response rate of approximately 25 %. A large number of current clinical trials therefore address possible combinatory approaches in order to make optimal use of possible synergisms and additive effects of the substances available to date, taking into account an acceptable side effect profile. In addition, many new therapeutic approaches are also being tested in clinical trials. In this context, developments in the field of antibody-drug conjugates and FGFR inhibitors with regards to the very recent FDA approvals are particularly noteworthy.The present review provides an overview of currently available treatment options in metastatic urothelial carcinoma of the bladder and especially focuses on future therapeutic approaches based on current clinical trials.

Long-term Outcomes of Salvage Lymph Node Dissection for Nodal Recurrence of Prostate Cancer After Radical Prostatectomy: Not as Good as Previously Thought

BACKGROUND

Long-term outcomes of patients treated with salvage lymph node dissection (sLND) for nodal recurrence of prostate cancer (PCa) remain unknown.

OBJECTIVE

To investigate long-term oncological outcomes after sLND in a large multi-institutional series.

DESIGN, SETTING, AND PARTICIPANTS

The study included 189 patients who experienced prostate-specific antigen (PSA) rise and nodal-only recurrence after radical prostatectomy (RP) and underwent sLND at 11 tertiary referral centers between 2002 and 2011. Lymph node recurrence was documented by positron emission tomography/computed tomography (PET/CT) scan using either ¹¹C-choline or ⁶⁸Ga prostate-specific membrane antigen ligand.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary outcome of the study was cancer-specific mortality (CSM). The secondary outcomes were overall mortality, clinical recurrence (CR), biochemical recurrence (BCR), and androgen deprivation therapy (ADT)-free survival after sLND. The probability of freedom from each outcome was calculated using Kaplan-Meier analyses. Cox regression analysis was used to predict the risk of prostate CSM after accounting for several parameters, including the use of additional treatments after sLND.

RESULTS AND LIMITATIONS

At long term, 110 and 163 patients experienced CR and BCR, respectively, with CR-free and BCR-free survival at 10 yr of 31% and 11%, respectively. After sLND, a total of 145 patients received ADT, with a median time to ADT of 41 mo. At a median (interquartile range) follow-up for survivors of 87 (51, 104) mo, 48 patients died. Of them, 45 died from PCa. The probabilities of freedom from cancer-specific and all-cause death at 10 yr were 66% and 64%, respectively. Similar results were obtained in sensitivity analyses in patients with pelvic-only positive PET/CT scan, as well as after excluding men on ADT at PET/CT scan and patients with PSA level at sLND higher than the 75th percentile. At multivariable analyses, patients who had PSA response after sLND (hazard ratio [HR]: 0.45; p = 0.001), and those receiving ADT within 6 mo from sLND (HR: 0.51; p = 0.010) had lower risk of death from PCa.

CONCLUSIONS

A third of men treated with sLND for PET-detected nodal recurrence of PCa died at long term, with PCa being the main cause of death. Salvage LND alone was associated with durable long-term outcomes in a minority of men who significantly benefited from additional treatments after surgery. Taken together, all these data argue against the use of metastasis-directed therapy alone for patients with node-only recurrent PCa. These men should instead be considered at high risk of systemic dissemination already at the time of sLND.

PATIENT SUMMARY

We assessed long-term outcomes of patients treated with salvage lymph node dissection (sLND) for node-recurrent prostate cancer (PCa). In contrast with prior evidence, we found that the majority of these men recurred after sLND and eventually died from PCa. A significant survival benefit associated with the administration of androgen deprivation therapy after sLND suggests that sLND should be considered part of a multimodal approach rather than an exclusive treatment strategy.

Assessing the Best Surgical Template at Salvage Pelvic Lymph Node Dissection for Nodal Recurrence of Prostate Cancer After Radical Prostatectomy: When Can Bilateral Dissection be Omitted? Results from a Multi-institutional Series

The best surgical template for salvage pelvic lymph node dissection (sLND) in patients with nodal recurrence from prostate cancer (PCa) after radical prostatectomy (RP) is currently unknown. We analyzed data of 189 patients with a unilateral positive positron emission tomography (PET) scan of the pelvic lymph node areas, who were treated with bilateral pelvic sLND after RP at 11 high-volume centers. The primary endpoint was missed contralateral disease at final pathology, defined as lymph node positive for PCa in the side opposite to the positive spot(s) at the PET scan. Overall, 93 (49%) and 96 (51%) patients received a ¹¹C-choline and a ⁶⁸Ga prostate-specific membrane antigen (PSMA) PET scan, respectively, and 171 (90%) and 18 (10%) men had one and two positive spots, respectively. The rate of missed contralateral PCa was 18% (34/189), with the rates being 17% (29/171) and 28% (5/18) in men with one and two positive spots, respectively. While the rate of contralateral disease did not differ between ⁶⁸Ga-PSMA and ¹¹C-choline (29% and 27%, respectively) among men with two positive spots, the rate of contralateral PCa was only 6% with ⁶⁸Ga-PSMA versus 28% with ¹¹C-choline in patients with a single positive spot. This finding was confirmed at multivariable logistic regression analysis predicting missed disease at final pathology after accounting for confounders (odds ratio: 0.24; p =  0.001). However, in men with a single positive spot at ⁶⁸Ga-PSMA PET/computed tomography, the rate of single confirmed lymph node metastasis at final pathology was only 33%, suggesting the need for extended template even if unilateral dissection is performed. Awaiting confirmatory studies, patients diagnosed with a single positive spot at the ⁶⁸Ga-PSMA PET scan might be considered for unilateral extended pelvic sLND. PATIENT SUMMARY: We assessed the risk of missing contralateral disease in patients with a positron emission tomography (PET) scan suggestive of unilateral nodal recurrence from prostate cancer (PCa) after radical prostatectomy and who were treated with bilateral salvage lymph node dissection (sLND). Variability exists according to the number of positive spots and PET tracer, with the lowest rate of missed PCa in men diagnosed with a single positive spot at a ⁶⁸Ga prostate-specific membrane antigen PET scan (6%). If replicated, our data suggest that these patients might be considered for unilateral extended pelvic sLND.

Multiparametric magnetic resonance imaging can exclude prostate cancer progression in patients on active surveillance: a retrospective cohort study

Objectives

To assess the ability of multiparametric MRI (mp-MRI) of the prostate to exclude prostate cancer (PCa) progression during monitoring patients on active surveillance (AS).

Methods

One hundred forty-seven consecutive patients on AS with mp-MRI (T2WI, DWI, DCE-MRI) at 3T were initially enrolled. Fifty-five received follow-up mp-MRI after a minimum interval of 12 months and subsequent targeted MR/US fusion-guided biopsy (FUS-GB) plus concurrent systematic transrectal ultrasound-guided (TRUS-GB) biopsy as reference standard. Primary endpoint was the negative predictive value (NPV) of the follow-up mp-MRI to exclude histopathologic tumor progression using PRECISE recommendations. Secondary endpoints were the positive predictive value (PPV), sensitivity, specificity, Gleason score (GS) upgrades, and comparison of biopsy method.

Results

Of 55 patients, 29 (53%) had a GS upgrade on re-biopsy. All 29 patients showed a tumor progression on follow-up mp-MRI. Fifteen of 55 patients (27%) displayed signs of tumor progression, but had stable GS on re-biopsy. None of the 11 patients (20%) without signs of progression on follow-up mp-MRI had a GS upgrade on re-biopsy. The NPV was 100%, PPV was 66%, sensitivity was 100%, and specificity 42%. FUS-GB resulted in GS upgrade significantly more often (n = 28; 51%) compared with TRUS-GB (n = 12; 22%; p < 0.001).

Conclusions

(Follow-up) Mp-MRI can reliably exclude PCa progression in patients on AS. Standard serial re-biopsies might be waived if follow-up mp-MRIs are stable. Over 60% of patients with signs of tumor progression on mp-MRI during AS had a GS upgrade on re-biopsy. Targeted re-biopsies should be performed if cancer progression or higher-grade PCa is suspected on mp-MRI.

Key Points

• None of the patients with unsuspicious mp-MRI had a GS upgrade in re-biopsy and mp-MRI might replace serial biopsies in these cases

• More than 60% of patients with mp-MRI signs of tumor progression had subsequent Gleason score (GS) upgrades

• Targeted re-biopsies should be performed in case of higher GS cancer suspicion on mp-MRI

Late toxicities and recurrences in patients with clinical stage I nonseminomatous germ cell tumor after one cycle of adjuvant BEP versus primary retroperitoneal lymph node dissection: A 13-years follow-up analysis of a phase III trial cohort

5512

Background: One cycle of adjuvant BEP has shown superiority in recurrence free survival over RPLND in patients (pts) with clinical stage (CS) I nonseminomatous germ cell tumor of the testis (NSGCT) (JCO 2008). We report recurrences and late toxicities of this randomized trial after 13 yrs of follow-up (FU). Methods: Questionnaires of 382 unselected pts with CS I NSGCT treated within a phase III trial comparing recurrence rate after 1 cycle of adjuvant BEP (arm A) vs. RPLND (arm B) were evaluated regarding recurrences and late toxicity. Overall (OS) and progression free survival (PFS) was calculated by Kaplan-Meier and arms were compared using logrank test. Categorial data were analyzed by chi-square test (PRISM v8). Results: In each arm 191 pts were analyzed as intention-to-treat with a median FU of 13.75 yrs (0-22.9 yrs); 3/191 pts (1.6 %) in arm A and 16/191 pts (8.4 %) in arm B had a recurrence. 20-yrs PFS in arm A / B was 97 % (CI 96-99 %) / 92 % (CI 90-95 %), ( p = .0049). 20-yrs OS in arm A / B was 90 % (CI 86-94 %) / 88 % (CI 86-94 %), ( p = .83). 23/382 (6 %) pts have died, 22/23 not related to testis cancer, 1/23 died of a recurrence in arm B. 8/191 pts (4.2 %) in arm A and 4/191 pts (2.1 %) in arm B showed metachronous secondary testis cancer ( p = .26). 5/191 pts (2.6 %) in arm A and 4/191 pts (2.1 %) in arm B developed other malignancies. 170/382 questionnaires were evaluable (arm A: 95; arm B: 75). 45 pts were lost to FU. There were no significant differences comparing both treatment arms regarding potentially treatment-related late toxicities. However, excluding pre-existing complaints, ototoxicity (9/95 (9 %) vs. 4/75 (5 %) pts, p = .31) was reported more frequently in arm A. Excluding pre-existing neurological conditions, peripheral neuropathy of all grades was more frequently reported in arm A (15/95 pts; 16 % vs. 9/75 pts; 12 % pts; p = .48). Retrograde ejaculation occurred more frequently after RPLND (9/95 pts; 9% vs. 18/75 pts; 24 %, p = .01). Conclusions: After more than 13 yrs of FU, recurrences in non-risk factor selected pts with CS I NSGCT remain to be significantly more frequent with RPLND. No excess mortality due to secondary malignancies was observed. Late toxicities did not differ between 1 cycle of BEP and RPLND. Only retrograde ejaculation was observed significantly more frequent after RPLND. With long-term observation, 1 cycle of BEP has not only a high efficacy to prevent recurrence but also seems to be tolerated without clinically relevant long-term toxicity.

Multicenter analysis of serum tumor markers, treatment patterns, and relapse in patients with testicular cancer in clinical stage IS

5052

Background: Testicular germ cell tumors (TGCT) in clinical stage I (CSI) are tumors confined to the testis without evidence of metastasis. Around 50% of all TGCT patients present with elevated serum tumor markers (TM) such as alpha-feto protein (AFP), beta-humanochoriongonadotropin (ß-HCG) and lactate-dehydrogenase (LDH). After ablatio testis, TMs usually return to normal according to half-life kinetics, however, in clinical stage IS (CSIS) TMs remain elevated or increase after surgery. Follow-up data on CSIS is scarce and our study aims to assess clinical characteristics and oncologic outcomes in a large TGCT cohort. Methods: In this multicenter study we collected data from 5 tertiary referring hospitals in Germany, included patients with CSIS and evaluated TM levels, treatment and the primary outcome relapse-free survival. False CSIS was defined as documented CSIS but TMs that returned to normal after respective half-life kinetics. Differences between predefined groups (chemotherapy, TM, true/false CSIS) was analyzed with fisher’s exact and chi-square test. Results: Overall, 2616 patient data files were analyzed. Forty-three patients (1.6%) were documented as CSIS of which 27 (63%) were true and 16 (37%) false CSIS. Six (14%) had seminomas and 37 (86%) non-seminomas. In the true CSIS group AFP, ß-HCG, AFP plus ß-HCG and LDH were elevated in 13, 6, 3 and 2 cases. Four true CSIS patients received surveillance, 21 had 3x or 2x courses of BEP (bleomycin, etoposide and cisplatin) and 2 carboplatin. Within the false CSIS group, 2 patients were treated with surveillance, 10 received 3x BEP, one 3x PEI (cisplatin, etoposide and ifosfamid) and 3 had carboplatin. Chi-Square test revealed no difference between true or false CSIS classification in respect to application of chemotherapy (any chemotherapy, p = 0.83). Relapse-free survival after 5 and 10 years was 88.9% and 77.8%, respectively. Three patients in the true CSIS group relapsed (2 seminomas had carboplatin, 1 non-seminoma had surveillance). All relapses were treated with 3 courses of BEP with no documented death in the CSIS population. Conclusions: Overall, less than 2% of all TGCT were documented CSIS of which 37% were falsely classified. We report a high proportion of relapse-free survival in CSIS treated with surveillance or BEP with a high heterogeneity in treatment patterns. Correct classification of CSIS remains of critical importance to avoid toxicity for patients that could be safely treated with surveillance.

Validation of the two best models to predict “benign” pathohistology in patients with advanced nonseminomatous germ cell tumors (NSGCT) undergoing postchemotherapy retroperitoneal lymph node dissection (PC-RPLND)

389

Background: The aim of our study is to validate and evaluate the two currently best performing prediction models (Vergouwe and Leao) for final pathohistology in NSGCT patients undergoing PC-RPLND and we introduce a new radiomics approach. Methods: We performed a retrospective analysis including 496 patients who underwent a PC-RPLND between 2008 and 2018 to validate the two prediction models using published formulas and thresholds. ROC were plotted and AUC was calculated. We determined the optimal cut point and used bootstrapping (1,000 replications) to estimate its variability. For radiomics, lymph nodes of 80 patients were identified on CT images, semiautomatically segmented with 93 radiographic features (pyRadiomics package). A linear support vector machine algorithm was applied to analyze reproducible radiomics features. A continuous reduction of features analyzed was performed using Random Forest algorithms and ROC analysis. Results: In our validation cohort, the Vergouwe model had a significantly better AUC compared to Leao model (0.749 [CI 0.706-0.792] vs. 0.689 [0.642-0.736], p=0.004) to predict benign histology. At a threshold of > 70% for the probability of benign disease, the Leao model would have avoided PC-RPLND in 8.6% with benign disease with an error rate of 5.6% for viable tumor. The Vergouwe model would avoid PC-RPLND in 23.4% with benign disease with an error rate of 12.7% for viable tumor/teratoma. Of the 93 radiomic features analyzed, 51 features were reproducible. Applying the trained algorithm on the training dataset resulted in an accuracy of 0.96 (93% sensitivity, 100% specificity, 100% PPV), on an independent validation cohort the accuracy was 0.81 (88% sensitivity, 72% specificity, 78% PPV). Conclusions: According to our data, the discriminatory accuracy of both models is not sufficient to safely select patients for surveillance strategy instead of PC-RPLND. The radiomics model is promising but needs prospective validation. Further studies including new biomarkers are needed to optimize the accuracy of potential prediction models.

Evaluation of the oncologic benefit of adjunctive surgery at time of postchemotherapy retroperitoneal lymph node dissection (PC-RPLND)

388

Background: PC-RPLND for advanced nonseminomatous germ cell tumors aims to resect all remaining metastatic tissue. The resection of adjacent visceral or vascular organs is commonly performed to achieving complete resection of the residual masses. However, the frequency of metastatic involvement of those organs with teratoma or vital cancer is currently unknown. Methods: We reviewed a cohort of 1181 patients who underwent PC-RPLND between 2008 and 2018 as a 2-center study and identified 235 (20%) cases of adjunctive surgery during PC-RPLND. We analysed the pathohistological presence of germ cell tumor elements in the resected organs: viable tumor (V), teratoma (T) or necrosis / fibrosis (N). Surgery associated complications were reported according to the Clavien-Dindo classification. Outcomes of subgroups were compared by using log-rank test. Results: V, T, N was present in 51 (21%), 91 (39%) and 93 (40%) of all patients with adjunct resected organs. In 235 patients, 316 adjunct organs were resected with 64 (27%) of these patients receiving a resection of multiple organs. The kidney was the most often resected organ (n = 74; V: 27% T: 39% N: 34%), followed by V. Cava (n = 66; V: 24% T: 36%, N: 40%) and partial liver resections (n = 48; V: 15%, T: 31%, N: 54%). Intraoperative complications occurred in 21% of patients (VT 32% vs N 17%, p = 0.021). Postoperative complications occurred in 35% of which 22% were Clavien Grad III-V showing no significant differences between VTN p = 0.093. 27% of all patients suffered from a relapse during a median follow-up of 22 months [0-180]. Patients with T or V in the resected specimens had a significantly reduced 5-year RFS compared to patients with only N (39%, 81%, p < 0.001). Conclusions: This study shows for the first time that 40% of all resections of adjunct organs are oncologically unnecessary due to the presence of N only in the pathological specimens. In case of doubt we propose an organ safe procedure with multiple intraoperative frozen section to avoiding oncologically unnecessary adjunctive surgeries especially nephrectomies and vascular resections. Additionally, a more accurate presurgical workup is required to spare patients with N from PC-RPLND.

Value of Dynamic Contrast-Enhanced (DCE) MR Imaging in Peripheral Lesions in PI-RADS-4 Patients

OBJECTIVE

 To assess the impact of dynamic contrast-enhanced imaging (DCE) in mp-MRI on prostate cancer (PCa) detection in a large patient cohort assigned to PI-RADS category 4.

METHOD

 This retrospective, single center cohort study includes 193 consecutive patients with PI-RADS assessment category 4 in mp-MRI (T2WI, DWI, DCE) at 3 T with targeted plus systematic biopsy combined as the reference standard. The detection of prostate cancer with and without the use of DCE was compared.

RESULTS

 Overall, the PCa detection rate in PI-RADS-4 patients was 62 % (119/193) with DCE and 52 % (101/193) without the inclusion of lesions upgraded on the basis of DCE. 48 % (92/193) had clinically significant PCa (csPCa; Gleason score ≥ 3 + 4 = 7) and 40 % (78/193) without use of DCE. 38 of the 193 patients (20 %) had peripheral lesions upgraded from PI-RADS category 3 to an overall PI-RADS category 4 due to focal positive DCE findings. Of these 38 patients, 18 had PCa including 14 with csPCa. Thus, 15 % (18/119) of the patients with PCa and 15 % (14/92) of the patients with csPCa were detected only based on additional DCE information.

CONCLUSION

 DCE prevents underestimation and misclassification of a significant number of cases of peripheral csPCa and might improve detection rates in PI-RADS-4 patients. The current PI-RADS decision rules regarding upgrading PI-RADS-3 lesions to category 4 due to positive DCE imaging are useful for PCa detection.

KEY POINTS

  · Positive peripheral DCE upgraded 20 % of patients in PI-RADS category 4 from category 3.. · Clinically significant PCa was found in almost 40 % of upgraded, peripheral PIRADS-3-lesions.. · 15 % of all csPCa in PI-RADS-4-patients was detected in DCE-upgraded lesions.. · In 7 % of all PI-RADS-4-cases csPCa would had been underestimated without DCE upgrade..

CITATION FORMAT

· Ullrich T, Quentin M, Arsov C et al. Value of Dynamic Contrast-Enhanced (DCE) MR Imaging in Peripheral Lesions in PI-RADS-4 Patients. Fortschr Röntgenstr 2020; 192: 441 - 447.

Comparison of analgesic techniques in MRI-guided in-bore prostate biopsy

OBJECTIVES

To evaluate different analgesic techniques in MRI-guided in-bore prostate biopsy (IB-GB) regarding the influence on patient procedural experience of pain.

METHODS

Two hundred fifty-two consecutive patients who had received an IB-GB either with intrarectal instillation of 2% lidocaine gel (n = 126, group A) or with periprostatic nerve block (PPNB) with 2% mepivacaine (n = 126, group B) were retrospectively included in this study. Pain scores were measured on a visual analog scale, the operating room time (ORT) was recorded for each biopsy and correlations between the parameters were analysed.

RESULTS

Pain scores for IB-GB were slightly lower in group B compared with group A (2.0 ± 1.9; 2.4 ± 1.7; p = 0.02). In group A, significantly more targeted biopsy cores were acquired (group B: 5.2 ± 1.1; group A: 5.6 ± 0.8; p < 0.01). ORT was comparable and not significantly different in both groups. There was only a weak correlation between pain scores and ORT in group B (r_S = 0.22; p = 0.01), but no correlation between pain scores and the number of biopsy cores or the prostate volume.

CONCLUSIONS

Pain levels are generally low for MRI-guided in-bore biopsy using either PPNB or intrarectal instillation of lidocaine gel. A statistically significant, slightly lower pain score was documented for PPNB and might be preferred when the focus is analgesia. On the other hand, due to the minor difference and easier administration, intrarectal gel instillation seems to be a reasonable practice for standard analgesia for MRI-guided in-bore biopsy.

KEY POINTS

• Pain levels were low for MRI-guided in-bore biopsy using either PPNB or intrarectal instillation of lidocaine gel as analgesic method. • PPNB prior to IB-GB resulted in a slightly lower pain score but required a higher effort. • Intrarectal gel anaesthesia seems to be a reasonable practice for standard analgesia for IB-GB in an outpatient setting.

Analysis of three models to predict pathohistology in patients undergoing postchemotherapy RPLND for (pcRPLND) advanced nonseminomatous germ cell tumors (NSGCT)

e16053

Background: We aim to validate the two best performing prediction models (Vergouwe and Leao) for final pathohistology in NSGCT patients undergoing pcRPLND and we introduce a new radiomics approach. Methods: A cohort of 496 patients treated between 2008 and 2018 was used to validate the 2 prediction modelsusing published formulas and thresholds.For group comparisons, we used t-test or chi-square test. ROC were plotted (sensitivity against 1-specificity) and AUC was calculated. We determined the optimal cut point and used bootstrapping (1,000 replications) to estimate its variability. A p-value of < 0.05 was considered statistically significant. For radiomics, lymph nodes identified on CT images, were semiautomatically segmented with 93 radiographic features (pyRadiomics package). A linear support vector machine algorithm was applied to analyze reproducible radiomics features. A continuous reduction of features analyzed was performed using Random Forest algorithms and ROC analysis. Results: The Vergouwe model had a significantly better AUC compared to Leao model (0.749 [CI 0.706-0.792] vs. 0.689 [0.642-0.736], p = 0.004) to predict benign histology. At a threshold of > 70% for the probability of benign disease, the Leao model would have avoided RLND in 8.6% with benign disease with an error rate of 5.6% for viable tumor. The Vergouwe model would avoid pcRPLND in 23.4% with benign disease with an error rate of 12.7% for viable tumor/teratoma. Of the 93 radiomic features analyzed, 51 features were reproducible. Applying the trained algorithm resulted in a AUC of 82% with a diagnostic sensitivity of 81% and a specificity of 83%. Conclusions: The discriminatory accuracy of both models is not sufficient to safely select patients for surveillance strategy instead of pcRPLND. The radiomics model is promising but needs prospective validation. Further studies including new biomarkers are needed to optimize the accuracy of potential prediction models.

Analysis of PI-RADS 4 cases: Management recommendations for negatively biopsied patients

PURPOSE

To evaluate if subgroups of patients assigned to MRI category PI-RADS 4 regarding clinical and MRI imaging aspects have distinct risks of prostate cancer (PCa) to facilitate adequate clinical management of this population, especially after negative targeted biopsy.

METHODS

This prospective, IRB approved single center cross-sectional study includes 931 consecutive patients after mp-MRI at 3 T for PCa detection. 193 patients with PI-RADS assessment category 4 received subsequent combined targeted MRI/US fusion-guided and systematic 12-core TRUS-guided biopsy as reference standard and were finally analyzed. The primary endpoint was PCa detection of PI-RADS 4 with MRI subgroup analyses. Secondary endpoints were analyses of clinical data, location of PCa, and detection of targeted biopsy cores.

RESULTS

PCa was detected in 119 of 193 patients (62%) including clinically significant PCa (csPCa; Gleason score ≥3 + 4 = 7) in 92 patients (48%). MRI subgroup analysis revealed 95% PCa (73% csPCa) in unambiguous PI-RADS 4 index lesions without additional, interfering signs of prostatitis in the peripheral zone or overlaying signs of severe stromal hyperplasia in the transition zone according to PI-RADS v2. Transition zone confined PI-RADS-4-lesions with overlaying signs of stromal hyperplasia showed PCa only in 11% (4% csPCa). Targeted biopsy cores missed the csPCa index lesion in 7% of the patients. PSA density (PSAD) was significantly higher in PCa patients.

CONCLUSIONS

Small csPCa can reliably be detected with mp-MRI by experienced readers, but can be missed by targeted MR/US fusion biopsy alone. Targeted re-biopsy of unambiguous (peripheral) PI-RADS-4-lesions is recommended; whereas transition zone confined PI-RADS-4-lesions with overlaying signs of stromal hyperplasia might be followed-up by re-MRI primarily.