A meta-analysis of patient outcomes with subcentimeter disease after chemotherapy for metastatic non-seminomatous germ cell tumor

Risk Factors for Relapse in Nonseminomatous Testicular Cancer After Postchemotherapy Retroperitoneal Lymph Node Dissection With Viable Residual Cancer

PURPOSE

No consensus exists on the management of men with nonseminoma and viable nonteratomatous germ cell tumor in the postchemotherapy retroperitoneal lymph node dissection (pcRPLND) specimen after first-line chemotherapy. We analyzed surveillance versus different adjuvant chemotherapy regimens and the influence of time to pcRPLND on oncologic outcomes.

METHODS

Data on 117 men treated with cisplatin-based first-line chemotherapy between 1990 and 2018 were collected from 13 institutions. All patients had viable nonteratomatous germ cell tumor in the pcRPLND specimen. Surgery was performed after a median of 57 days, followed by either surveillance (n = 64) or adjuvant chemotherapy (n = 53). Primary end points were progression-free survival (PFS), cancer-specific survival (CSS), and overall survival (OS).

RESULTS

After controlling for International Germ Cell Cancer Cooperative Group risk group and percent of viable malignant cells found at RPLND, no difference was observed between men managed with surveillance or adjuvant chemotherapy regarding PFS (hazard ratio [HR], 0.72 [95% CI, 0.32 to 1.6]; P = .4), CSS (HR, 0.69; 95% CI, 0.20 to 2.39; P = .6), and OS (HR, 0.78 [95% CI, 0.25 to 2.44]; P = .7). No statistically significant differences for PFS, CSS, or OS were observed on the basis of chemotherapy regimen or in men treated with pcRPLND ≤57 versus >57 days after first-line chemotherapy. Residual disease with <10% versus ≥10% viable cancer cells were associated with a longer PFS (HR, 3.22 [95% CI, 1.29 to 8]; P = .012). Relapse in the retroperitoneum was observed in 34 (29%) men.

CONCLUSION

Men with a complete resection at pcRPLND and <10% viable cells have favorable outcomes without further treatment. Complete retroperitoneal resection seems more important than early pcRPLND.

Validation of a prediction model for post-chemotherapy fibrosis in nonseminoma patients

OBJECTIVE

To validate Vergouwe's prediction model using the Swedish and Norwegian Testicular Cancer Group (SWENOTECA) RETROP database and to define its clinical utility.

MATERIALS AND METHODS

Vergouwe's prediction model for benign histopathology in post-chemotherapy retroperitoneal lymph node dissection (PC-RPLND) uses the following variables: presence of teratoma in orchiectomy specimen; pre-chemotherapy level of alpha-fetoprotein; β-Human chorionic gonadotropin and lactate dehydrogenase; and lymph node size pre- and post-chemotherapy. Our validation cohort consisted of patients included in RETROP, a prospective population-based database of patients in Sweden and Norway with metastatic nonseminoma, who underwent PC-RPLND in the period 2007-2014. Discrimination and calibration analyses were used to validate Vergouwe's prediction model results. Calibration plots were created and a Hosmer-Lemeshow test was calculated. Clinical utility, expressed as opt-out net benefit (NBopt-out ), was analysed using decision curve analysis.

RESULTS

Overall, 284 patients were included in the analysis, of whom 130 (46%) had benign histology after PC-RPLND. Discrimination analysis showed good reproducibility, with an area under the receiver-operating characteristic curve (AUC) of 0.82 (95% confidence interval 0.77-0.87) compared to Vergouwe's prediction model (AUC between 0.77 and 0.84). Calibration was acceptable with no recalibration. Using a prediction threshold of 70% for benign histopathology, NBopt-out was 0.098. Using the model and this threshold, 61 patients would have been spared surgery. However, only 51 of 61 were correctly classified as benign.

CONCLUSIONS

The model was externally validated with good reproducibility. In a clinical setting, the model may identify patients with a high chance of benign histopathology, thereby sparing patients of surgery. However, meticulous follow-up is required.

Risk of residual cancer after complete response following first-line chemotherapy in men with metastatic non-seminomatous germ cell tumour and International Germ Cell Cancer Cooperative Group intermediate/poor prognosis: A multi-institutional retrospective cohort study

INTRODUCTION

Current guidelines recommend surveillance in metastatic non-seminomatous germ cell tumour patients treated with first-line-chemotherapy and a complete clinical response (normalisation of serum tumour markers and residual masses <1 cm). However, this recommendation is based on a series including patients with good prognosis according to International Germ Cell Cancer Cooperative Group prognostic group (IGCCCG-PG). The aim of this study was to analyse the proportion of residual teratoma and survival among patients with intermediate/poor IGCCCG-PG and a complete clinical response after first-line-chemotherapy.

MATERIAL & METHODS

This is a retrospective study of men with intermediate/poor IGCCCG-PG, who had a complete clinical response after first-line chemotherapy. Patients were either followed by surveillance or treated with post-chemotherapy retroperitoneal lymph node dissection (pcRPLND).

RESULTS

Between 2009 and 2018, 143 men with intermediate (n = 83) or poor (n = 60) IGCCCG-PG were treated at 11 international centres. Among 33 patients treated with pcRPLND, the specimen showed teratoma and viable cancer in 16 (48%) and 4 (12%). During a median a 7-year follow-up, 20/110 (18%) patients managed with surveillance relapsed, of whom seven (6%) had a retroperitoneal-only relapse versus 2/33 patients managed with pcRPLND relapsed. No difference was observed regarding overall survival (OS) among men treated with pcRPLND or surveillance (5-year OS, 93% and 89%, p-value = 0.35). The median time-to-recurrence among men on surveillance was 1.3 years (range: 0.3-9.1), and the most common sites of relapses included retroperitoneum (11%), chest (5%), and bones (4%).

CONCLUSIONS

While most men with intermediate/poor IGCCCG-PG harbour teratoma/cancer in the retroperitoneum despite a complete response to first-line-chemotherapy, only 6% managed with surveillance relapsed in the retroperitoneum. There was no significant difference in OS between the two groups.

Advances in diagnosis and treatment of testicular cancer

Testicular cancer is a curable cancer. The success of physicians in curing the disease is underpinned by multidisciplinary advances. Cisplatin-based combination chemotherapy and the refinement of post-chemotherapy surgical procedures and diagnostic strategies have greatly improved long term survival in most patients. Despite such excellent outcomes, several controversial dilemmas exist in the approaches to clinical stage I disease, salvage chemotherapy, post-chemotherapy surgical procedures, and implementing innovative imaging studies. Relapse after salvage chemotherapy has a poor prognosis and the optimal treatment is not apparent. Recent research has provided insight into the molecular mechanisms underlying cisplatin resistance. Phase 2 studies with targeted agents have failed to show adequate efficacy; however, our understanding of cisplatin resistant disease is rapidly expanding. This review summarizes recent advances and discusses relevant issues in the biology and management of testicular cancer.

Narrative review of developing new biomarkers for decision making in advanced testis cancer

Management of testicular germ cell tumor (GCT) patients is based on clinical determinants, mainly CT scan and serum tumor markers (alpha-fetoprotein, beta subunit of HCG and LDH). Treatment decisions are usually straightforward for patients with clear evidence of metastatic disease, confirmed either by imaging tests or by unequivocal elevated tumor markers. However, there are several clinical scenarios where the assessment of metastatic disease is complicated by the limited specificity of the current imaging tests and serum tumor markers. These include patients with clinical stage IIA GCT with negative tumor markers and patients with post-chemotherapy residual disease where, in absence of clear indicators of GCT, decision making and patient treatment allocation become challenging. Therefore, more accurate biomarkers are critical to reduce the risk of under-or over-treatment and to always deliver the most optimal therapy. The objectives of this narrative review are to review the available publications about micro-RNAs in GCT s and their potential clinical applications. Two clusters of micro-RNAs, miR-371a-3p and miR-302/367, specifically expressed by both seminoma and non-seminoma GCT and easily detectable in the peripheral blood, have demonstrated to be promising in this endeavor. Large prospective trials are ongoing to define the operating characteristics of these biomarkers and their clinical utility to improve GCT patient management and reduce the error rate deriving from clinical uncertainty, therefore reducing the risk of sub-optimal treatments.

Surveillance of postchemotherapy subcentimeter residual retroperitoneal mass in metastatic nonseminomatous germ cell tumor: Does how you measure matter?

BACKGROUND

Approximately 70% to 80% of patients with metastatic nonseminomatous germ cell tumor (NSGCT) treated with cisplatin-based chemotherapy achieve a complete response, defined as normalization of serum tumor markers and either no residual retroperitoneal mass (RRM) or an RRM <1.0 cm. While there is universal agreement that patients with an RRM ≥1.0 cm should undergo retroperitoneal lymph node dissection (RPLND), many institutions including ours recommend surveillance for patients who achieve a complete response. However, studies have not defined which axis of the RRM should be considered when deciding between surveillance and RPLND.

PATIENTS AND METHODS

Good-risk metastatic NSGCT patients treated with cisplatin-based chemotherapy who achieved a complete response and underwent surveillance were identified using our institution's electronic medical records. A post-hoc review was performed by a blinded radiologist. The RRM dimensions in the transaxial short axis (TSA), transaxial long axis (TLA), and craniocaudal axis (CCA) were recorded. Differences in the frequency of recurrence between groups with an RRM <1.0 cm and ≥1.0 cm in the TLA and CCA were assessed using the Fisher exact test.

RESULTS

Thirty-nine patients who met study criteria were included. At a median follow-up of 63.8 months, 2 patients (5.1%) recurred. Both were successfully treated with salvage chemotherapy and RPLND. Thirteen (33%) and 27 (69%) patients had an RRM ≥1.0 cm in the TLA and CCA, respectively. There were no statistically significant differences in the risk of recurrence between patients with an RRM <1.0 cm and ≥1.0 cm in the TLA (P = 0.54) or CCA (P = 0.53).

CONCLUSIONS

Surveillance is an effective strategy in good-risk NSGCT patients with a postchemotherapy RRM <1.0 cm in the TSA. Our study suggests referencing the TSA and not the TLA or CCA may avoid unnecessary postchemotherapy RPLNDs.

Promising novel therapies for relapsed and refractory testicular germ cell tumors

INTRODUCTION

Germ cell tumors (GCTs) are the most common solid malignancies in young men. The overall cure rate of GCT patients in metastatic stage is excellent, however; patients with relapsed or refractory disease have poor prognosis. Attempts to treat refractory disease with novel effective treatment to improve prognosis have been historically dismal and the ability to predict prognosis and treatment response in GCTs did not sufficiently improve in the last three decades.

AREAS COVERED

We performed a comprehensive literature search of PubMed/MEDLINE to identify original and review articles (years 1964-2020) reporting on current improvement salvage treatment in GCTs and novel treatment options including molecularly targeted therapy and epigenetic approach. Review articles were further searched for additional original articles.

EXPERT OPINION

Despite multimodal treatment approaches the treatment of relapsed or platinum-refractory GCTs remains a challenge. High-dose chemotherapy (HDCT) regimens with autologous stem-cell transplant (ASCT) from peripheral blood showed promising results in larger retrospective studies. Promising results from in vitro studies raised high expectations in molecular targets. So far, the lacking efficacy in small and unselected trials do not shed a light on targeted therapy. Currently, wide inclusion of patients into clinical trials is highly advised.

Management of residual disease after chemotherapy in germ cell tumors

PURPOSE OF REVIEW

Although testicular cancer remains a highly curable malignancy, challenges and uncertainty still remain in certain aspects of management. Residual disease after chemotherapy in patients with germ cell tumors (GCT) remains one of these challenges. We aim to highlight the recent literature on the management of residual disease after chemotherapy in GCT and the emerging innovations that may provide further guidance into this area.

RECENT FINDINGS

A subset of patients with GCT will have residual disease after chemotherapy, and management of these patients involves highly skilled multidisciplinary experts including medical oncologists, surgeons, radiologists, and pathologists. Management options depend on histologic subtype, either seminoma or nonseminoma, and involve size criteria, possible further imaging modalities, and tumor markers. Even with these tools at highly specialized expert centers, uncertainty in management remains, and recent literature has explored the use of newer biomarkers to aid in these cases.

SUMMARY

Postchemotherapy residual masses in GCT can prove to be complicated cases to manage. Balancing survival with quality of life outcomes is important and requires a multidisciplinary team experienced in treating GCT.

Long-term Surveillance of Patients with Complete Response Following Chemotherapy for Metastatic Nonseminomatous Germ Cell Tumor

BACKGROUND

There is controversy regarding the management of patients with normal markers and residual masses (≤1 cm) after chemotherapy for nonseminomatous germ cell tumors (NSGCTs).

OBJECTIVE

To determine long-term outcomes of a surveillance strategy in such patients.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective review of our multidisciplinary testicular cancer database was performed. All patients who underwent primary chemotherapy for metastatic NSGCTs were identified between 1981 and 2016. A complete response (CR) was defined as normalization of serum tumor markers and a ≤1 cm residual mass in the largest axial dimension following chemotherapy. All such patients were surveilled.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Outcome variables of interest were time to death, time to cancer-specific survival, and time to relapse. Overall survival and relapse-free survival were calculated using the Kaplan-Meier method, and the cumulative incidence of cause-specific survival rates was calculated using competing risk analysis. The impact of risk group and chemotherapy regimen on relapse-free survival was assessed using log-rank test.

RESULTS AND LIMITATIONS

During the study period, 1429 metastatic germ cell tumor patients were treated with primary chemotherapy. CR was achieved in 191 (18.5%) NSGCT patients. The median age at diagnosis was 27.4 yr, with a median follow-up of 81.1 mo. The majority had American Joint Committee on Cancer stage II at diagnosis (I: 23.8%; II: 49.2%; III: 27%) and International Germ Cell Cancer Collaborative Group good-risk disease (good: 78%; intermediate: 17.8%; poor: 4.2%). Of the 191 patients with a CR, 175 (91.6%) never relapsed and remain disease free. Sixteen (8.4%) patients relapsed after a median of 11.3 mo (range 1-332 mo), with over half (nine patients; 4.7%) relapsing in the retroperitoneum only and salvaged successfully with postchemotherapy retroperitoneal lymph node dissection (PC-RPLND) alone. Of these nine patients, only two (1%) had viable disease in the PC-RPLND specimen. The remaining seven patients had relapses outside the retroperitoneum and received salvage chemotherapy ± postchemotherapy resection. Overall, nine (4.7%) patients have died, but only four (2.1%) from testis cancer.

CONCLUSIONS

Our data, the largest series to date, confirm that surveillance is safe and effective for men who achieve a CR following chemotherapy for metastatic NSGCTs.

PATIENT SUMMARY

Surveillance is a safe strategy for patients who achieve a complete response following chemotherapy for metastatic testis cancer.

Simultaneous Vs Sequential Retroperitoneal, Thoracic and Cervical Resection of Post Chemotherapy Residual Masses in Patients With Metastatic Nonseminomatous Germ Cell Tumors of the Testis

OBJECTIVE

To compare a simultaneous vs sequential approach to residual post chemotherapy mass resections in metastatic testis cancer.

METHODS

A retrospective review was performed of patients who underwent retroperitoneal and thoracic/cervical resection of post chemotherapy residual masses between 2002 and 2018. Group 1: "Simultaneous" (Combined Retroperitoneal and Thoracic/Cervical resections on the same date); Group 2: "Sequential" (Retroperitoneal and Thoracic/Cervical resections at separate dates).

RESULTS

During the study period, 35 simultaneous and 17 sequential resections were performed. The median age at surgery was 28 years (Range 16-61). The median follow-up from last surgical procedure was 62.7 months (Range 0.4-194). Histology revealed teratoma in 38 (73.1%) patients, necrosis in 8 (15.4%) and viable tumor in 6 (11.5%). Discordant pathology findings between thoracic/cervical and abdominal resections were noted in 16 (30.8%) patients. No differences were observed between the simultaneous vs sequential groups in median operating time (585 minutes vs 545 minutes, P = .64), blood loss (1300 vs 1300 mls, P = .42), or length of stay (9 vs 11 days, P = .14). There was no difference between the 5-year (65.7% vs 68.6%) relapse-free survival between the 2 groups (P = .84) or the 5-year (88.6% vs 100%) overall and disease-specific survival (P = .25).

CONCLUSION

Simultaneous resection of retroperitoneal and thoracic/cervical post chemotherapy metastases is a feasible in some patients. It requires multidisciplinary collaboration and a longer primary procedure.

Current management and management controversies in early- and intermediate-stage of nonseminoma germ cell tumors

Early stage nonseminomatous germ cell tumor (NSGCT) remains a treatable disease, with stage I cancer specific survival exceeding 95%. Using a risk-adapted approach; active surveillance (AS), adjuvant chemotherapy, and retroperitoneal lymph node dissection (RPLND) all options for treatment; with surveillance being increasingly used. With persistently elevated markers (stage IS), chemotherapy remains the hallmark of treatment. Management of stage II NSGCT varies based on status of tumor markers. With negative markers, both induction chemotherapy and upfront RPLND remain options. Management of a residual mass <1 cm after chemotherapy remains controversial, with AS and nerve-sparing RPLND considered options. The development of miR-371a-3p microRNA shows promise a novel biomarker for testicular cancer (GCT). Despite controversies in management, cures for NSGCT are achievable in 95-99% of patients.

ESMO Consensus Conference on testicular germ cell cancer: diagnosis, treatment and follow-up

The European Society for Medical Oncology (ESMO) consensus conference on testicular cancer was held on 3-5 November 2016 in Paris, France. The conference included a multidisciplinary panel of 36 leading experts in the diagnosis and treatment of testicular cancer (34 panel members attended the conference; an additional two panel members [CB and K-PD] participated in all preparatory work and subsequent manuscript development). The aim of the conference was to develop detailed recommendations on topics relating to testicular cancer that are not covered in detail in the current ESMO Clinical Practice Guidelines (CPGs) and where the available level of evidence is insufficient. The main topics identified for discussion related to: (1) diagnostic work-up and patient assessment; (2) stage I disease; (3) stage II-III disease; (4) post-chemotherapy surgery, salvage chemotherapy, salvage and desperation surgery and special topics; and (5) survivorship and follow-up schemes. The experts addressed questions relating to one of the five topics within five working groups. Relevant scientific literature was reviewed in advance. Recommendations were developed by the working groups and then presented to the entire panel. A consensus vote was obtained following whole-panel discussions, and the consensus recommendations were then further developed in post-meeting discussions in written form. This manuscript presents the results of the expert panel discussions, including the consensus recommendations and a summary of evidence supporting each recommendation. All participants approved the final manuscript.

Postchemotherapy Resection of Residual Mass in Nonseminomatous Germ Cell Tumor

The introduction of cisplatin-based chemotherapy has revolutionized the care of patients with disseminated testicular germ cell tumors. Although a majority are cured with chemotherapy alone, surgical resection continues to play a role because one-third will have residual mass after chemotherapy. In this article, we review the current indications for postchemotherapy resection in nonseminomatous germ cell tumors, including masses greater than 1 cm, resection after salvage chemotherapy, with elevated markers, after late relapse, and for growing teratoma syndrome. We also highlight technical considerations of this often-challenging surgery, including the need for adjunctive procedures, extraretroperitoneal resections, and modern techniques to minimize morbidity.

Current controversies on the role of retroperitoneal lymphadenectomy for testicular cancer

Retroperitoneal lymph node dissection (RPLND) is an important component of the multimodal treatment which cures most patients diagnosed with testicular germ cell tumors. Considering the high cure rates achieved, research focus in recent years has been directed toward improving quality of life and decreasing long-term treatment related sequelae. Consequently, the role of RPLND has evolved over the past 3 decades in both low-stage and advanced testicular cancer. The use of RPLND in clinically stage I and low volume stage II disease may offer the advantages of treating retroperitoneal teratoma which is present in 15% to 20% of patients, avoiding chemotherapy and reducing the need for frequent imaging during follow-up. Similarly, ongoing studies are evaluating the safety and effectiveness of RPLND for the treatment of early stage seminoma to avoid the long-term effects of chemotherapy and radiotherapy. RPLND is traditionally used for the treatment of residual masses >1 cm after completion of chemotherapy. Its role in subcentimeter residual masses remains somewhat controversial given the fact that 25% to 30% of these patients are found to harbor either teratoma or viable nonteratomatous germ cell tumors. The presence of teratoma increases the probability of teratoma in metastatic sites. Modified unilateral templates were developed based on early mapping studies with the aim of preserving antegrade ejaculation. Recent data suggests initial mapping studies underestimated the risk of contralateral retroperitoneal metastases which may reach 32%. Furthermore, antegrade ejaculation may be preserved in >95% of patients undergoing bilateral nerve sparing primary RPLND and >80% undergoing nerve-sparing PC-RPLND, which, in our view is the more prudent oncologic approach. Recently, multiple series have demonstrated the safety and short-term efficacy of minimally invasive RPLND; however, larger studies with prolonged follow-up are required to validate the long-term oncologic efficacy of newer techniques.

Nodule Size After Chemotherapy and Primary-Tumor Teratoma Components Predict Malignancy of Residual Pulmonary Nodules in Metastatic Nonseminomatous Germ Cell Tumor

BACKGROUND

The treatment goal for visceral metastatic nonseminomatous germ cell tumor (NSGCT) is to remove any residual teratoma or viable NSGCT after chemotherapy. However, this provides no therapeutic benefit to patients whose metastases necrotize on their own. This study therefore analyzed NSGCTs with pulmonary metastases to determine preoperative factors that predict necrosis and could help identify patients who might be treated with monitoring rather than surgery.

METHODS

The study retrospectively analyzed 41 patients (135 metastatic pulmonary nodules) treated from 1997 to 2016 for NSGCT who showed tumor marker normalization after chemotherapy. Relationships between clinicopathologic characteristics and necrosis in resected pulmonary specimens were analyzed.

RESULTS

Receiver operating characteristic analysis of the pulmonary nodules showed 9 mm to be the optimal cutoff length for predicting necrosis. The logistic regression model showed that absence of teratoma components in the primary tumor and all pulmonary nodules shorter than 10 mm after chemotherapy both were independent predictors of pathologic necrosis in pulmonary specimens. No patients experienced late recurrence (i.e., > 2 years afterward).

CONCLUSIONS

The presence of teratoma components in primary tumors and nodular size after chemotherapy predict the pathology of residual pulmonary nodules. Patients whose residual nodules all are shorter than 10 mm and who have no primary-tumor teratoma components might be candidates for careful monitoring before pulmonary resection.

[When is surgical resection of metastases in testicular germ cell tumors indicated and is there a scientific basis?]

Surgical resection of metastases represents an integral part of curative management in patients with testicular germ cell tumors (GCT). Primary nerve-sparing retroperitoneal lymph node dissection (nsRPLND) for low volume metastases in clinical stages I-IIB has to be differentiated from the more complex and more extensive postchemotherapeutic procedures. In Europe, primary nerve-sparing retroperitoneal lymph node dissection (nsRPLND) for clinical stage I nonseminomatous GCT (NSGCT) plays a subordinate. In clinical stage IIA/B, nsRPLND is indicated for patients with marker-negative metastases in whom cure rates of about 65% can be achieved with surgery alone. For clinical stage IIA/B seminomas, nsRPLND represents an individual, still experimental procedure with high cure rates. Postchemotherapy residual tumor resection (pRTR) for advanced seminomas is only indicated in the context of a FDG-PET/CT-positive residual mass >3 cm in diameter. For NSGCT, pRTR is indicated in patients with residual masses >1 cm and negative or plateauing tumor markers to resect persisting teratoma or vital cancer. Complete resection of all masses including resection of adjacent vascular, visceral or skeletal metastases is mandatory to achieving the highest cure rate possible. Due to the complexity and the lower rate of significant morbidity and mortality, these procedures should be done at tertiary referral centers.

Serum miRNA Predicts Viable Disease after Chemotherapy in Patients with Testicular Nonseminoma Germ Cell Tumor

PURPOSE

Retroperitoneal lymph node dissection is recommended for residual masses greater than 1 cm after chemotherapy of nonseminomatous germ cell tumors. Currently there is no reliable predictor of post-chemotherapy retroperitoneal lymph node dissection histology. Up to 50% of patients harbor necrosis/fibrosis only so that a potentially morbid surgery has limited therapeutic value. In this study we evaluated the ability of defined serum miRNAs to predict residual viable nonseminomatous germ cell tumors after chemotherapy.

MATERIALS AND METHODS

Levels of serum miRNA, including miR-371a-3p, miR-373-3p and miR-367-3p, were measured using the ampTSmiR (amplification targeted serum miRNA) test in 82 patients, including 39 in cohort 1 and 43 in cohort 2, who were treated with orchiectomy, chemotherapy and post-chemotherapy retroperitoneal lymph node dissection. miRNA levels were compared to clinical characteristics and serum tumor markers, and correlated with the presence of viable germ cell tumor vs fibrosis/necrosis and teratoma. ROC analysis was done to determine miRNA discriminative capacity.

RESULTS

miRNA levels were significantly associated with disease extent at chemotherapy and they decreased significantly after chemotherapy. Conventional serum tumor marker levels were uninformative after chemotherapy. However, after chemotherapy miRNA levels remained elevated in patients harboring viable germ cell tumor in post-chemotherapy retroperitoneal lymph node dissection specimens. miR-371a-3p demonstrated the highest discriminative capacity for viable germ cell tumors (AUC 0.874, 95% CI 0.774-0.974, p <0.0001). Using an adapted hypothetical cutoff of 3 cm or less for surgical intervention miR-371a-3p correctly stratified all patients with viable residual retroperitoneal germ cell tumors with 100% sensitivity (p = 0.02).

CONCLUSIONS

Our study demonstrates for the first time the potential value of miR-371a-3p to predict viable germ cell tumors in residual masses after chemotherapy. Prospective studies are required to confirm clinical usefulness.

A New Model to Predict Benign Histology in Residual Retroperitoneal Masses After Chemotherapy in Nonseminoma

BACKGROUND

Postchemotherapy retroperitoneal lymph node dissection (pcRPLND) is indicated in testicular cancer patients with normalised or plateaued serum tumour markers and residual retroperitoneal lesions >1cm. Challenges remain in predicting postchemotherapy residual mass (pcRM) histology, which may lead to unnecessary surgery.

OBJECTIVE

To develop an accurate model to predict pcRM histology in patients with nonseminomatous germ cell tumours (NSGCTs).

DESIGN, SETTING, AND PARTICIPANTS

A retrospective review of 335 patients undergoing pcRPLND for metastatic NSGCTs to develop a model to predict benign histology in retroperitoneal pcRM. Our model was compared with others and externally validated.

INTERVENTION

Chemotherapy and pcRPLND.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Multivariable logistic regression to evaluate the presence of benign histology, and fractional polynomials to allow for a nonlinear association between continuous variables and the outcome. The final Princess Margaret model (PMM) was selected based on the number of variables used, reliability, and discriminative capacity to predict benign pcRM.

RESULTS AND LIMITATIONS

PMM included the presence of teratoma in the orchiectomy, prechemotherapy α-fetoprotein, prechemotherapy mass size, and change in mass size during chemotherapy. Model specificity was 99.3%. Compared with Vergouwe et al's model, PMM had significantly better accuracy (C statistic 0.843 vs 0.783). PMM appropriately identified a larger number of patients for whom pcRPLND can safely be avoided (13.9% vs 0%). Validated in external cohorts, the model retained high discrimination (C statistic 0.88 and 0.80). Larger and prospective studies are needed to further validate this model.

CONCLUSIONS

Our clinical model, externally validated, showed improved discriminative ability in predicting pcRM histology when compared with other models. The higher accuracy and reduced number of variables make this a novel and appealing model to use for patient counselling and treatment strategies.

PATIENT SUMMARY

Princess Margaret model accurately predicted postchemotherapy benign histology. These results might have clinical impact by avoiding unnecessary retroperitoneal lymph node dissection and consequently changing the paradigm of advanced testicular cancer treatment.

Modern Management of Testicular Cancer

Testicular cancer is a rare urological malignancy with high cure rate. The development of highly effective systemic treatment regimens along with advances in surgical treatment of advanced disease has led to continued improvement in outcomes. Patients with testicular cancer who are treated following the treatment guideline mostly achieved high quality of life and long-term survival. However, patients who were identified as having non-guideline directed care were at significantly higher risk of relapse. In this book chapter, we introduce in depth the modern management of testicular cancer, including diagnosis, staging and risk stratification, treatment strategies of seminoma and non-seminoma germ cell tumors, follow-up protocols, and salvage treatment for disease relapse. We also review new studies and updates on medical and surgical management of advanced testicular cancer.

[Diagnosis, treatment and follow-up of testicular cancer]

BACKGROUND

Testicular cancer is a disease of young adult men, and it is curable in most cases. Even in advanced disease, cure rates reach 80 % nowadays. This was achieved by consistently performing studies concerning the different stages of disease.

TREATMENT AND FOLLOW-UP CARE

The concept of treatment is interdisciplinary. After removal of the affected testis, histology and stage determine further therapy, which can be active surveillance, polychemotherapy, radiotherapy, surgery, or a combination of these. Curability also has consequences for the long-term follow-up. We speak about long-term survivorship. Besides looking for recurrences, it is also necessary to observe and treat long-term toxicities caused by the different therapeutic procedures.

CONCLUSION

Because testicular cancer is rare with about 4500 cases annually, treatment-especially for advanced disease-should be performed at centers. In addition, it is possible to obtain a second opinion using the Interdisciplinary German Testicular Study Group website.

Advances in the treatment of testicular cancer

Germ cell tumors (GCT) are relatively uncommon, accounting for only 1% of male malignancies in the United States. It has become an important oncological disease for several reasons. It is the most common malignancy in young men 15-35 years old. GCTs are among a unique numbers of neoplasms where biochemical markers play a critical role. Finally, it is a model of curable cancer. In this review we discuss cancer epidemiology, genetics, and therapeutic principles. Recent advances in the management of stage I GCT and controversies in the management of post chemotherapy residual mass are presented.

Radiation exposure from diagnostic imaging in young patients with testicular cancer

OBJECTIVES

Risks associated with high cumulative effective dose (CED) from radiation are greater when imaging is performed on younger patients. Testicular cancer affects young patients and has a good prognosis. Regular imaging is standard for follow-up. This study quantifies CED from diagnostic imaging in these patients.

METHODS

Radiological imaging of patients aged 18-39 years, diagnosed with testicular cancer between 2001 and 2011 in two tertiary care centres was examined. Age at diagnosis, cancer type, dose-length product (DLP), imaging type, and frequency were recorded. CED was calculated from DLP using conversion factors. Statistical analysis was performed with SPSS.

RESULTS

In total, 120 patients with a mean age of 30.7 ± 5.2 years at diagnosis had 1,410 radiological investigations. Median (IQR) surveillance was 4.37 years (2.0-5.5). Median (IQR) CED was 125.1 mSv (81.3-177.5). Computed tomography accounted for 65.3 % of imaging studies and 98.3 % of CED. We found that 77.5 % (93/120) of patients received high CED (>75 mSv). Surveillance time was associated with high CED (OR 2.1, CI 1.5-2.8).

CONCLUSIONS

Survivors of testicular cancer frequently receive high CED from diagnostic imaging, mainly CT. Dose management software for accurate real-time monitoring of CED and low-dose CT protocols with maintained image quality should be used by specialist centres for surveillance imaging.

KEY POINTS

• CT accounted for 98.3 % of CED in patients with testicular cancer. • Median CED in patients with testicular cancer was 125.1 mSv • High CED (>75 mSv) was observed in 77.5 % (93/120) of patients. • Dose tracking and development of low-dose CT protocols are recommended.