Questioning the Value of Fluorodeoxyglucose Positron Emission Tomography for Residual Lesions After Chemotherapy for Metastatic Seminoma: Results of an International Global Germ Cell Cancer Group Registry

Retroperitoneal Lymph Node Dissection: Perioperative Management and Updates on Surgical Techniques

Retroperitoneal lymph node dissection (RPLND) has been an integral part of a multimodal treatment strategy in testicular cancer. Surgeons, over the last decade, have advanced the understanding of RPLND by adopting perioperative care pathways, innovative biomarkers, surgical techniques, and developing algorithms for managing complications. This review summarizes updates on various aspects including the enhanced recovery after surgery pathway, imaging techniques, surgical approaches, dissection templates, and the management of complications. We conclude that RPLND has undergone significant evolution and refinement in the modern era and will continue to hold a critical role in the care of patients with testicular cancer.

Optimal imaging techniques across the spectrum of testicular cancer

Over the years, several imaging techniques have been used in the diagnosis and management of testicular cancer. We compartmentalize disease stages into preorchiectomy, stage 1, initial stage 2 and 3 and postchemotherapy stage 2 and 3. We then elaborate on various imaging modalities that are relevant to each of these stages. We also describe evolving imaging tools that have shown promise. We attempt to provide a comprehensive review of these techniques over the spectrum of testicular cancer.

Serum Levels of MicroRNA-371a-3p for Predicting the Histology of Postchemotherapy Residual Masses of Germ Cell Tumours

BACKGROUND AND OBJECTIVE

Serum levels of microRNA-371a-3p (M371) represent a novel and sensitive biomarker of germ cell tumours (GCTs). This study analysed the utility of M371 to identify viable cancer (VC) in postchemotherapy (pc) residual masses with the underlying goal of avoiding overtreatment.

METHODS

A multicentric, prospective diagnostic study was conducted in 180 GCT patients undergoing pc resection of residual masses. A correlation of M371 measurement results with the histological presence of VC in masses was found. A receiver operating characteristic analysis was performed for exploring the performance characteristics of the test.

KEY FINDINGS AND LIMITATIONS

The sensitivity was found to be 68.9%, specificity 99.3%, area under the curve 0.813, positive predictive value 0.969, and negative predictive value 0.905; sensitivity is significantly associated with the percentage of VC in the mass. In specimens with ≤10% VC, there were 33.3% elevated M371 levels as opposed to 85.7% in specimens with >50% VC. Teratoma and somatic-type malignancy do not express M371. A lack of a central pathological review is a limitation.

CONCLUSIONS AND CLINICAL IMPLICATIONS

The M371 test can identify 68.9% of patients with VC in pc masses. However, cases with <10% VC in the mass may escape detection. Teratoma does not express M371. The test alone cannot correctly identify patients requiring pc surgery, but it may be a tool for scheduling the extent of surgery.

PATIENT SUMMARY

The microRNA-371a-3p (M371) test can identify about two-thirds of patients with viable cancer in residual metastatic masses following chemotherapy for germ cell tumours. Only masses with high percentages of viable cancer cells can be identified, and the histological subtype teratoma remains undetected with the test.

Evaluation of post-chemotherapy residual seminomatous masses by 18F-fluorodeoxyglucose PET/CT using tumor-to-liver ratio - conundrum or solution?

OBJECTIVE

Assessment of diagnostic accuracy of FDG-PET/CT in the detection of viable disease in post-chemotherapy seminomatous residual masses using visual interpretation, SUVmax, and T/L ratio.

METHODS

This is a retrospective study assessing the post-chemotherapy seminomatous residual masses of size >3 cm. The PET/CT scan findings were interpreted visually for presence of residual disease which were validated from histopathology reports or imaging follow-up for a maximum of 3 years. SUVmax and T/L ratios were also determined for all the residual lesions. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value NPV were calculated and compared for all three parameters along with ROC analysis to obtain an optimal cutoff value for SUVmax and T/L ratio, respectively.

RESULTS

Sample size was 49. Out of these 49 patients, 8 had validation of PET results with histopathology. Rest was validated with imaging follow-up. FDG-PET was positive in 30 patients and negative in 19 patients by visual interpretation. The sensitivity, specificity, PPV, and NPV by this method were 100%, 62.5%, 73%, and 100%, respectively. The SUVmax and T/L ratios were also calculated for these lesions. The cutoff for these two variables was 4.56 and 1.21, respectively. The sensitivity, specificity, PPV, and NPV at these cutoffs were 76%, 87.5%, 86%, 77.7%, and 92%, 87.5%, 88%, 91%, respectively.

CONCLUSION

FDG-PET has a favorable diagnostic value in predicting viable disease in post-chemotherapy seminomatous residual masses and using T/L ratio cutoff of 1.21 will increase the specificity of the test.

Postchemotherapy retroperitoneal lymph node dissection (PC-RPLND) for seminoma: Limitations of surgical intervention after first-line chemotherapy

PURPOSE

Patients with relapsed seminoma after first-line chemotherapy can be treated with salvage chemotherapy or postchemotherapy retroperitoneal lymph node dissection (PC-RPLND). Based on prior experience, surgical management can have worse efficacy and increased morbidity compared to nonseminomatous germ cell tumor. Our aim was to characterize the surgical efficacy and difficulty in highly selected patients with residual disease after first-line chemotherapy.

MATERIALS AND METHODS

The Indiana University testis cancer database was queried to identify men who underwent PC-RPLND for seminoma between January 2011 and December 2021. Included patients underwent first-line chemotherapy and had evidence of retroperitoneal disease progression.

RESULTS

We identified 889 patients that underwent PC-RPLND, of which only 14 patients were operated on for seminoma. One patient was excluded for lack of follow-up. Out of 13 patients, only 3 patients were disease free with surgery only. Median follow up time was 29.9 months (interquartile ranges : 22.6-53.7). Two patients died of disease. The remaining 8 patients were treated successfully with salvage chemotherapy. During PC-RPLND, 4 patients required nephrectomy, 1 patient required an aortic graft, 2 patients required a partial ureterectomy, and 3 patients required partial or complete caval resection.

CONCLUSION

The decision between salvage chemotherapy and PC-RPLND as second-line therapy can be challenging. Salvage chemotherapy is effective but is associated with short and long-term morbidity. Surgical efficacy in this setting seems to be limited, but careful selection of patients may lead to surgical success without affecting the ability to receive any systemic salvage therapies if necessary or causing life-threating morbidity.

MicroRNA-371a-3p-The Novel Serum Biomarker in Testicular Germ Cell Tumors

INTRODUCTION

Testicular germ cell tumors (TGCTs) are a paradigm for the use of serum tumor markers in clinical management. However, conventional markers such as alpha-fetoprotein (AFP), beta-human chorionic gonadotropin (hCG), and lactate dehydrogenase (LDH) have quite limited sensitivities and specificities. Within the last decade, the microRNA-371a-3p (miR371) emerged as a possible new biomarker with promising features.

AREAS COVERED

This review covers the typical features as well as possible clinical applications of miR371 in TGCT patients, such as initial diagnosis, therapy monitoring, and follow-up. Additionally, technical issues are discussed.

EXPERT OPINION

With a sensitivity of around 90% and specificity >90%, miR371 clearly outperforms the classical serum tumor markers in TGCTs. The unique features of the test involve the potential of modifying recent standards of care in TGCT. In particular, miR371 is expected to aid clinical decision-making in scenarios such as discriminating small testicular TGCT masses from benign ones prior to surgery, assessing equivocal lymphadenopathies, and monitoring chemotherapy results. Likewise, it is expected to make follow-up easier by reducing the intensity of examinations and by sparing imaging procedures. Overall, the data presently available are promising, but further prospective studies are required before the test can be implemented in standard clinical care.

Imaging of pediatric testicular tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper

Primary intratesticular tumors are uncommon in children, but incidence and risk of malignancy both sharply increase during adolescence. Ultrasound is the mainstay for imaging the primary lesion, and cross-sectional modalities are often required for evaluation of regional or distant disease. However, variations to this approach are dictated by additional clinical and imaging nuances. This paper offers consensus recommendations for imaging of pediatric patients with a known or suspected primary testicular malignancy at diagnosis and during follow-up.

Seminoma arising in splenogonadal fusion: a case report and literature review

BACKGROUND

Splenogonadal fusion (SGF) is a rare congenital malformation in which the spleen is abnormally connected to the gonads or to the mesonephric derivatives. There is no obvious causality between SGF and testicular neoplasm. However, cryptorchidism, which is a well-known risk factor of testicular germ cell tumors, are the most frequent malformations associated with SGF. To our knowledge, there are only four reported cases of SGF associated with testicular neoplasm so far. Herein, we reported a patient of this condition, and briefly reviewed the related literature.

CASE PRESENTATION

A 48-year-old man was diagnosed with bilateral cryptorchidism 30 years prior, and only underwent a right orchiopexy for the left testicle could not be explored during the operation. At that time, doctors failed to realize the possibility of SGF due to the lack of sufficient knowledge of this condition. This time, the patient was treated for a left abdomen mass that was diagnosed as stage III metastatic seminoma. Then, a right orchiectomy, robot-assisted laparoscopic left retroperitoneal tumor resection, and left retroperitoneal lymph node dissection was performed after four cycles of BEP (bleomycin + etoposide + cisplatin) systemic chemotherapy in our center. The final diagnosis of SGF was made by postoperative pathology. The patient was re-examined in our center at 3 months and 6 months after the operation, and no obvious abnormalities were found.

CONCLUSIONS

Surgeons should always bear in mind the possibility of association between bilateral cryptorchidism and splenogonadal fusion to avoid malignant transformation caused by delayed treatment.

[Multimodal treatment of testicular cancer: chemotherapy, surgery or radiotherapy?]

BACKGROUND

Metastatic testicular germ cell tumors patients require histology- and stage-appropriate therapy to achieve optimal therapeutic outcomes.

OBJECTIVES

This work focuses on the interdisciplinary presentation of current recommendations for the treatment of metastatic germ cell tumor patients.

MATERIALS AND METHODS

The interdisciplinary recommendations were formulated based on the German S3 guideline and supplemented by recent literature.

RESULTS

Using a stage-specific and guideline-based treatment approach, interdisciplinary cooperation between urology, oncology, and radiotherapy is mandatory to successfully achieve a high rate of cure and, in the case of complex advanced tumors, also the most effective therapy possible. The question of optimal treatment approaches for seminoma in cSII A/B remains particularly challenging.

CONCLUSION

Since treatment of advanced or multiple relapsed germ cell tumor patients remains complex, patients should be referred for an online second opinion ( https://urologie.ekonsil.org ).

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.

Hodentumoren aus klinischer Sicht

Hintergrund

Keimzelltumoren des Hodens sind die häufigste maligne Tumorerkrankung bei Männern im Alter von 15–40 Jahren. Die Unterscheidung von Seminomen und Nichtseminomen hat prognostische Bedeutung und ist für Therapieplanung und Nachsorge essenziell. Durch interdisziplinäre, stadiengerechte Therapie haben Keimzelltumoren generell eine sehr gute Prognose. Eine Übertherapie sollte wegen möglicher Langzeitfolgen vermieden werden. Hierbei hilft die Risikobeurteilung anhand klinischer und pathologischer Faktoren.

Ziel der Arbeit

Darstellung der (histo-)pathologischen Charakteristika, die die uroonkologische Therapieplanung maßgeblich beeinflussen.

Material und Methoden

Nichtsystematischer Übersichtsartikel über die relevanten (histo-)pathologischen Befunde für die klinische Therapieplanung im interdisziplinären Kontext.

Ergebnisse

Zentrale Pathologiebefunde für Kliniker:Innen sind: (i) Identifikation eines Keimzelltumors, ggf. durch Nachweis eines Chromosom-12p-Zugewinns, (ii) Subtypenspezifizierung und (iii) Angabe von Risikofaktoren (insbesondere Invasion von Lymphgefäßen und/oder Rete testis und Tumorgröße). Molekularpathologische Untersuchungen i. S. von Mutationsanalysen sind angesichts einer sehr geringen Mutationslast und bislang fehlender prädiktiver Marker und zielgerichteter Therapieoptionen nicht Teil der Routinediagnostik.

Diskussion

Ein detaillierter, idealerweise synoptischer histopathologischer Befundbericht ist Grundlage der Planung und Durchführung einer leitlinienkonformen, risikoadaptierten Therapie und neben der bildgebenden Diagnostik und der Bestimmung der Serumtumormarker AFP und β‑HCG (letztere insbesondere bei Nichtseminomen) mitentscheidend, um die guten Heilungsaussichten zu wahren und eine Übertherapie zu vermeiden.

End-of-Treatment FDG PET-CT (EOT-PET) in Patients with Post-Chemotherapy Masses for Seminoma: Can We Avoid Further Intervention?

Anjana JoelContext  Patients with seminoma present with advanced disease. End-of-treatment (EOT) positron emission tomography-computed tomography (PET-CT) is done to assess response and direct management of post-chemotherapy residual masses. Purpose  This article assesses the utility of EOT PET-CT in the management of post-chemotherapy residual lymph nodal masses seminoma. Materials and Methods  We analyzed all patients with seminoma who underwent an EOT PET-CT from January 2015 to January 2020 at our center and calculated the positive predictive value (PPV) and negative predictive value (NPV) of EOT PET-CT in the entire cohort of patients and among subgroups. Results  A total of 34 male patients underwent EOT PET-CT. Fourteen (41.2%) were stratified as good risk and 20 (58.8%) as intermediate risk. The median follow-up was 23 months (interquartile range: 9.75-53 months). In 23 patients there were residual masses of size more than 3 cm at the EOT PET scan. EOT PET was positive as per the SEMPET criteria in 18 (78%) out of 23 patients. None underwent retroperitoneal lymph node dissection. All four who underwent image-guided biopsy, showed only necrosis on pathology. One patient with positive mediastinal node (standardized uptake value 13.6) had granulomatous inflammation. There was no relapse or progression during this period of follow-up. The NPV for EOT PET-CT for the entire cohort, > 3 cm, and > 6 weeks cutoff were 100%, respectively. The PPV for EOT PET-CT for the entire cohort, > 3 cm residual mass, and > 6 weeks cutoff were 8.7, 11.11, and 6.67%, respectively. Conclusion  EOT PET-CT has a low PPV and high NPV in predicting viable tumor in post-chemotherapy residual masses among patients with seminomatous germ cell tumors. If required, EOT PET positivity can be confirmed by a biopsy or reassessed with a repeat PET-CT imaging to document persistent disease prior to further intervention.

Serum Levels of MicroRNA-371a-3p (M371) Can Predict Absence or Presence of Vital Disease in Residual Masses After Chemotherapy of Metastatic Seminoma

Background

Radiological evaluation of postchemotherapy residual masses of metastatic seminoma is characterized by poor diagnostic accuracy. Serum levels of microRNA-371a-3p (M371) involve high specificity and sensitivity for the primary diagnosis of seminoma. We evaluated if M371 levels can indicate the presence of vital disease in postchemotherapy residual masses in patients with metastatic seminoma.

Methods

Twenty-three seminoma patients (median age 52 years) with residual masses had posttreatment measurements of serum M371 levels (group A), fourteen of whom had measurements also beforehand. The posttreatment results were compared with the clinical outcome during follow-up. Eleven patients with complete remission after treatment of metastatic seminoma (group B) and 33 men with non-malignant testicular diseases (group C) served as controls. M371 serum levels were measured by quantitative real-time PCR using miR-30b-5p as endogenous control. An evaluation was performed with descriptive statistical methods.

Results

Twenty-two patients of Group A had uneventful follow-up so far, twenty-one of whom had M371 level &lt;5, and one other had a mildly elevated level below relative quantity (RQ) = 10. One patient with a level of RQ = 26.2 rapidly progressed. The median posttreatment M371 level of the non-progressing patients of group A is not significantly different from the median level of the control group with complete remission (B). Before treatment, the median M371 levels in groups A and B were 507.6 and 143.9, respectively. In both groups, significant drops in M371 levels resulted from treatment.

Conclusion

Normal M371 serum levels at the time of completion of treatment of metastatic seminoma indicate the absence of vital seminoma in residual masses, while elevated levels &gt;RQ = 10 predict the presence of disease. The optimal timing of M371 measurement after chemotherapy and the appropriate cutoff level still need to be determined. Based on the present results, measuring serum M371 levels involves the potential of a novel tool for assessing postchemotherapy residual masses of metastatic seminoma.

Vigilance is key: Metastatic teratoma in an enlarging retroperitoneal mass after treatment of advanced seminoma – a case report

We present the case of a patient with pure seminoma in the orchiectomy specimen with retroperitoneal mass and a minimally elevated alpha fetoprotein (AFP). The patient received chemotherapy with positron emission tomography (PET) imaging demonstrating minimal fluorodeoxyglucose (FDG) uptake consistent with no viable tumour. Subsequent imaging revealed slow growth in the residual mass with a mildly elevated fluctuating AFP. A robotic-assisted laparoscopic retroperitoneal lymph node dissection was performed revealing metastatic teratoma. This case illustrates the potential for a missed or ‘burned out’ occult NSGCT in a patient with pure seminoma and the importance of post-treatment surveillance. In advanced seminoma, PET may be used to distinguish viable tumour from necrosis in post-chemotherapy residual masses. However, it is unable to distinguish between teratoma and necrosis in non-seminomatous germ cell tumours (NSGCT). Minimally elevated AFP could be a normal variant or signify a component of NSGCT in such cases.

Level of evidence: 4

Leydig cell tumor of the testis: an incidental finding at 18F-FDG PET/CT imaging

Background

Leydig cell tumors (LCTs) represent the most common form of stromal tumors. We reported the 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) findings of a patient with testicular LCT.

Case presentation

A 50-year-old man with a history of end-stage renal disease and renal transplantation 19 years ago. One year earlier, he started to have a chronic rejection. During the investigation to determine the cause of chronic rejection, a suspicious lesion in the graft with a collection around it was seen on ultrasound (US) images, raising the possibility of post-transplant lymphoproliferative disorder (PTLD). The patient was referred for further evaluation by whole body 18F-FDG PET/CT imaging. The image finding revealed an incidental hypermetabolic focal lesion in the right testicle—no other specific findings in the remaining parts of the body nor definitive FDG avid lymphadenopathy to suggest PTLD. Testicular US was requested and showed a well-defined right-sided heterogeneous hypoechoic intratesticular focal mass at the upper pole of the right testis with significant internal vascularity on the color Doppler imaging. The patient underwent a right radical orchidectomy, and the tumor was pathologically confirmed as an LCT.

Conclusion

In our case, 18F-FDG-PET/CT has been helpful in incidentally detecting this rare testicular tumor in a patient with suspected PTLD.

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.

Contemporary options and future perspectives: three examples highlighting the challenges in testicular cancer imaging

PURPOSE

One of the main issues in testicular germ cell tumors (TGCTs) management is to reduce the necessary amount of treatment to achieve cure. Excess treatment burden may arise from late diagnosis of the primary as well as from false positive or negative staging results. Correct imaging is of paramount importance for successful management of TGCT. The aim of this review is to point out the current state of the art as well as innovative developments in TGCT imaging on the basis of three common challenging clinical situations.

METHODS

A selective literature search was performed in PubMed, Medline as well as in recent conference proceedings.

RESULTS

Regarding small testicular lesions, recent studies using elastography, contrast-enhanced ultrasound or magnetic resonance imaging (MRI) showed promising data for differentiation between benign and malignant histology. For borderline enlarged lymph nodes FDG-PET-CT performance is unsatisfactory, promising new techniques as lymphotropic nanoparticle-enhanced MRI is the subject of research in this field. Regarding the assessment of postchemotherapeutic residual masses, the use of conventional computerized tomography (CT) together with serum tumor markers is still the standard of care. To avoid overtreatment in this setting, new imaging modalities like diffusion-weighted MRI and radiomics are currently under investigation. For follow-up of clinical stage I TGCTs, the use of MRI is non-inferior to CT while omitting radiation exposure.

CONCLUSION

Further efforts should be made to refine imaging for TGCT patients, which is of high relevance for the guidance of treatment decisions as well as the associated treatment burdens and oncological outcomes.

Editorial by Bendu K. Konneh, John T. Lafin and Aditya Bagrodia on pp. 341-342 of this issue: MicroRNA-371a-3p as a blood-based biomarker in testis cancer

MicroRNAs (miRNAs) are small noncoding RNAs involved in the regulation of mRNA transcription and translation, and possess all desirable features of an ideal tumor marker. Of almost 31 different miRNA clusters identified in germ cell tumors (GCTs), miR-371a-3p has shown exceptionally high sensitivity and specificity for both seminomatous and nonseminomatous GCTs. It is easily obtainable and correlates well with tumor burden. Recent multi-institutional prospective studies have shown promising test characteristics for miR-371a-3p as a diagnostic blood-based biomarker for GCT prior to orchiectomy including 80%-100% sensitivity and 90%-100% specificity. This accuracy may address other unmet needs in the management of patients with GCT. Early studies have suggested the utility of miR-371a-3p in detecting occult nodal metastasis in high-risk clinical stage I and early stage II disease. Ongoing clinical trials including SWOG 1823 and AGCT1531 are specifically designed to confirm the utility of miR-371a-3p in clinical stage I GCT. Despite its strong association with viable GCT after treatment with chemotherapy, miR-371a-3p does not seem to accurately predict the presence of teratoma in residual lesions. Also, standardization of extraction and interpretation methods is a necessary step to assure uniform results across different institutions.

Radiotherapy for Post-Chemotherapy Residual Mass in Advanced Seminoma: A Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography-Based Risk-adapted Approach

AIMS

There is a lack of consensus regarding the management of post-chemotherapy residual mass in classical seminoma. The use of fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET-CT) may aid the detection of residual masses harbouring viable disease and help to tailor therapy. The aim of this study was to evaluate if PET-CT could identify patients who will benefit from locoregional radiotherapy.

MATERIALS AND METHODS

This ethics-approved study included patients with advanced classical seminoma primarily treated with standard platinum-based first-line chemotherapy. Patients were either observed or given adjuvant radiotherapy based on the clinician's preference and followed up. For this study, patients were stratified into two groups based on FDG PET-CT residual nodal maximum standardised uptake value (SUVmax): low risk (SUVmax <3) and high risk (SUVmax ≥3). Further subgroup analysis was carried out for patients with residual nodal size ≥3 cm and SUVmax ≥3, and this was considered as the very high risk group. The diagnostic accuracy of FDG PET-CT was assessed and survival was compared between the different groups.

RESULTS

Sixty-nine patients were included in the study: 48 patients were observed and 21 received radiotherapy. The low and high risk groups contained 50.7% and 49.3% of the patients, respectively. The very high risk subgroup had 24 patients. At a median follow-up of 44 months, locoregional failures in the radiotherapy and observation cohorts were 0% and 30% (P = 0.059) in the very high risk subgroup and 5.8% and 29.4% (P = 0.078) in the high risk group. The positive predictive value for the very high risk and high risk groups was 30% and 17.1%, respectively. The benefit of locoregional control failed to translate into overall survival benefit.

CONCLUSION

A tailored, FDG PET-based risk-adapted treatment approach can refine the management of post-chemotherapy residual masses in seminoma. In this study, with the largest cohort of advanced seminoma patients treated with radiotherapy reported to date, radiotherapy seems to benefit patients with post-chemotherapy residual mass SUVmax ≥3.

Primary mediastinal germ cell tumours: real world experience in the low middle income (LMIC) setting

PURPOSE

Primary mediastinal germ cell tumours (PMGCTs) are rare; with limited data available about their outcomes and optimal treatment in the low middle income countries setting. We studied the clinical profile of patients with PMGCT treated at our centre in order to estimate their survival outcomes and to identify prognostic factors affecting the same.

PATIENTS AND METHODS

Fifty-seven patients with PMGCTs treated between April 2001 and June 2019 were included. Baseline characteristics, details of first line chemotherapy, response rates, toxicity and surgical outcomes were noted. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method.

RESULTS

Among 57 male patients (seminoma = 20 and nonseminomatous = 37), the median follow-up was 10 months (range: 1-120 months). For mediastinal seminoma, 9 (45%) and 11 (55%) patients had good and intermediate risk disease, respectively. Nineteen patients (95%) received BEP (Bleomycin, etoposide and cisplatin) chemotherapy. 94.7% had partial responses and median event-free survival was not reached. All patients were alive and disease free at 2 years. For primary mediastinal nonseminomatous germ cell tumours (PMNSGCTs), all patients were poor risk. Thirty-four (91.8%) received BEP/EP chemotherapy as first line. Responses were PRM+ (partial response with elevated markers) in 7 (20.5%) and PRM- in 12 (35.2%). The incidence of febrile neutropenia was 50% and 55.8% in seminole and PMNSGCT, respectively. The median OS was 9.06 months and median PFS was 4.63 months for PMNSGCT. The proportion of patients alive at 1 year and 2 years were 35% and 24.3%, respectively.

CONCLUSION

Primary mediastinal seminomas are rarer and have better survival outcomes. Treatment of PMNSGCT is still a challenge and is associated with poorer survival outcomes.

Intricacies of Radiographic Assessment in Testicular Germ Cell Tumors

Testicular germ cell tumors (GCTs) are malignancies with a unique biology, pathology, clinical appearance, and excellent outcomes. A correct radiographic assessment of GCTs is extremely important for the clinical management in several typical scenarios. Advancements in the field of diagnostic medicine bring an increasing number of sophisticated imaging methods to increase the performance of imaging studies. The conventional computed tomography (CT) remains the mainstay of diagnostic imaging in the management of GCTs. While certain improvements in the sensitivity and specificity are suggested with magnetic resonance (MR) imaging with lymphotrophic nanoparticles in evaluating retroperitoneal lymph nodes during the staging procedure, further exploration in larger prospective studies is needed. A common diagnostic dilemma is assessing the post-chemotherapy residual disease in GCTs. Several studies have consistently shown advantages in the utility of positron emission tomography (PET) scanning in post-chemotherapy residual retroperitoneal lymph nodes in patients with seminoma, but not with non-seminoma. Recommendations suggest that seminoma patients with a residual disease in the retroperitoneum larger than 3 cm should be subjected for PET scanning with 18-fluorodeoxyglucose. Relatively high sensitivity, specificity and a negative predictive value (80-95%) may guide clinical decision to spare these patients of high morbidity of an unnecessary surgery. However, a positive predictive value of around 50% renders PET scanning difficult to interpret in the case of positive finding. These patients often require extremely difficult surgical procedures with the high risk of post-operative morbidity. Therefore, seminoma patients with PET positive residual masses larger than 3 cm still remain a serious challenge in the decision making of nuclear medicine specialist, oncologists, and urologic surgeons. In this article, we aim to summarize data on controversial dilemmas in staging procedures, active surveillance, and post-chemotherapy assessment of GCTs based on the available published literature.

The impact of a supranetwork multidisciplinary team (SMDT) on decision-making in testicular cancers: a 10-year overview of the Anglian Germ Cell Cancer Collaborative Group (AGCCCG)

BACKGROUND

The germ cell supranetwork multidisciplinary team (SMDT) for the Anglian Network covers a population of 7.5 million.

METHODS

We reviewed 10 years of SMDT discussion and categorised them into five domains ((1) overall outcome, (2) chemotherapy regimens-untreated disease and salvage therapy, (3) radiology, (4) pathology and (5) complex cases) to assess the impact of the SMDT.

RESULTS

A total of 2892 new cases were reviewed. In the first 5 years, patients with good prognosis disease had poorer survival in low-volume vs high-volume centres (87.8 vs 95.3, p = 0.02), but the difference was no longer significant in the last 5 years (93.3 vs 95.1, p = 0.30). Radiology review of 3206 scans led to rejection of the diagnosis of progression in 26 cases and a further 10 cases were down-staged. There were 790 pathology reviews by two specialised uropathologists, which lead to changes in 75 cases. 18F-fluorodeoxyglucose (18FDG) PET-CT was undertaken during this time period but did not help to predict who would have viable cancer. A total of 26 patients with significant mental health issues who were unable to give informed consent were discussed.

CONCLUSION

SMDT working has led to an improvement in outcomes and refining of treatment in patients with germ cell tumours.

PET imaging in testicular tumours

PURPOSE OF REVIEW

Testicular cancer is rare, but its incidence is expected to rise. [18F] fluorodeoxyglucose ([18F]FDG) PET/computed tomography (CT) added role in testicular cancer management has been defined in a set of specific clinical settings. The current review focuses on recent advances in the employment of PET/CT in testicular cancer patients.

RECENT FINDINGS

[18F]FDG PET/CT is not recommended for initial staging or for suspected testicular tumours. PET/CT role in testicular cancer management is mainly for the assessment of seminoma residual masses after therapy (>3 cm). Although [18F]FDG PET/CT has a very high negative predictive value, its positive predictive value varies across studies: appropriate PET/CT scheduling after therapy and a careful history are mandatory for accurate interpretation. Interim PET/CT could prove valuable to spare subsequent chemotherapy cycles in patients already in remission, reducing related toxicity. The role of [18F]FDG in nonseminoma tumours is hampered by the low sensitivity in teratoma.

SUMMARY

[18F]FDG PET/CT is currently used for the assessment of seminoma residual masses (>3 cm) after therapy. A negative PET could also spare unnecessary further chemotherapy cycles in responding patients, reducing toxicity. Although rare, testicular secondary lesions can be detected with non[18F]FDG tracers when PET/CT is performed for other primary tumours.

[What does the oncologist need from the pathologist in testicular cancer?]

BACKGROUND

Testicular type II germ cell tumours (GCTs) are an exemplar of a curable cancer and the most common malignancy in males aged ≤35 years. Even in metastatic stages, about 70% of patients can be cured by cisplatin-based chemotherapy and multimodal treatments. For patients failing platinum-based standard therapy, prognosis is poor and novel biomarkers and therapeutic options are urgently needed.

OBJECTIVES

Discussion of desired histopathological information to guide urologists' and oncologists' decision making in the treatment of male GCTs.

MATERIAL AND METHODS

A narrative review of histopathological key features of male GCT tissue samples for clinical decision making.

RESULTS

Histopathological workup is crucial to identify (i) a GCT origin in cancers of unknown primary based on isochromosome 12p (i(12p)) detection, (ii) the different type II GCT subtypes, and (iii) risk factors, i.e. lymphovascular or rete testis invasion, among others. Proper histopathological diagnosis is indispensable for guideline-endorsed, histology-driven, and risk-adapted treatment decisions, hereby helping to maintain treatment success while reducing the therapeutic burden and potential long-term sequelae of multimodal treatments. For refractory patients failing standard treatment options, prognosis remains poor and, so far, neither predictive or prognostic biomarkers nor novel therapeutic targets have been established.

CONCLUSIONS

Close interaction and interdisciplinary discussion of histopathologic and radiologic findings and established risk factors including serum tumour markers is crucial for successful treatment including intensified strategies, where necessary, or prevention of overtreatment, where possible.

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.

Prognostic Role of Early Interim Fluorodeoxyglucose Positron Emission Tomography in Patients With Advanced Seminoma Undergoing Standard Treatment

BACKGROUND

Patients with advanced seminoma have an exceedingly favorable prognosis. Studies aiming to reduce the total treatment burden and side effects in patients with well-defined disease and very good prognosis are warranted.

PATIENTS AND METHODS

In a prospective observational study, patients with advanced stage seminoma were treated with bleomycin, etoposide, and cisplatin (BEP) or EP according to guidelines. Fluorodeoxyglucose with positron emission tomography and computed tomography (FDG-PET/CT) examinations were performed at baseline, after 2 cycles (PET/CT2) in all patients, and after chemotherapy at the physician's discretion. Disease response to treatment assessed by PET/CT was qualitatively evaluated by 2 independent nuclear medicine physicians. Contrast-enhanced CT scans were also performed according to guidelines (at baseline, after treatment, during follow-up). The study's primary endpoint was to evaluate the association between PET/CT2 findings and relapse-free survival.

RESULTS

From January 2009 to January 2017, a total of 75 consecutive patients were enrolled, of whom 70 were included for analysis. The clinical disease stage was IIA-B and IIC-III in 40% and 60%, respectively. By local assessment, 46 PET/CT2 scans (65.7%) were reported as negative, and 46% of these patients had stage IIC-III disease. Five-year relapse-free survival of PET/CT2-positive patients was 75% (95% confidence interval, 60-95) compared to 97.8% (95% confidence interval, 93.7-100) of PET/CT2-negative patients (P = .002). In univariate analyses, PET/CT2 was significantly associated with relapse-free survival (P = .02).

CONCLUSIONS

No residual FDG uptake after 2 cycles of conventional chemotherapy is prognostic in advanced seminoma, but it may be useful to optimize the standard prognostic risk groups and may be tested within larger prospective clinical trials of chemotherapy deescalation.

Surgical strategies for postchemotherapy testis cancer

The surgical management of disseminated disease has long been an essential component in the management of patients with testis cancer. While the indications for surgery have been narrowed since the advent of cisplatin based chemotherapy, resection remains essential to provide long-term survival. The indications for surgery vary by histology and rely on adequate preoperative imaging to evaluate for residual disease. Surgery for postchemotherapy testis cancer is challenging and requires that surgeons be prepared for extraretroperitoneal resections and adjunctive procedures as necessary. Herein, we review the imaging options that are essential for surgical planning and the various surgical techniques that are often necessary in this challenging situation.

Advanced Testis Cancer

Management of advanced testis cancer requires dedicated attention to the nuances of the disease to not only optimize cure but also ensure lifelong health. We are rapidly entering an era of precision medicine with novel biomarker discoveries that will undoubtedly change the treatment paradigm in both early- and late-stage disease.

MicroRNAs as Biomarkers for Germ Cell Tumors

Two clusters of microRNAs have been discovered highly expressed by seminoma and nonseminoma germ cell tumors. They are secreted in blood of patients with testicular germ cell tumors and can be extracted from the serum or plasma and quantified by real-time-polymerase chain reaction. Results have confirmed the feasibility of the technique and demonstrated that sensitivity and specificity of those microRNAs in detecting viable germ cell tumors are higher than with current methods. If operation characteristics are confirmed in larger studies, those microRNAs will be valuable to manage equivocal clinical scenarios characterized by high uncertainty and high risk of over-treatment or under-treatment.

The role of 18F-FDG-PET/CT in evaluating retroperitoneal masses -Keeping your eye on the ball!

Background

Testicular germ cell tumour is the commonest malignancy affecting males aged between 15 and 35, with an increased relative risk amongst those with a history of cryptorchidism. In patients presenting with locoregional metastatic disease, retroperitoneal and pelvic soft tissue masses are common findings on ultrasound and computed tomography, which has several differential diagnoses within this demographic cohort. On staging ¹⁸F-FDG-PET/CT, understanding the typical testicular lymphatic drainage pathway facilitates prompt recognition of the pathognomonic constellation of unilateral absence of testicular scrotal activity, and FDG-avid nodal masses along the drainage pathway. We describe the cases of three young males presenting with abdominopelvic masses, in whom FDG-PET/CT was helpful in formulating a unifying diagnosis of metastatic seminoma, retrospectively corroborated by a history of testicular maldescent.

Case presentations

In all three cases, the patients were males aged in their 30s and 40s who were brought to medical attention for back and lower abdominal pain of varying duration. Initial imaging evaluation with computed tomography and/or ultrasound revealed large abdominopelvic soft tissue masses, with lymphoproliferative disorders or soft tissue sarcomas being high on the list of differential diagnoses.

As such, they were referred for staging FDG-PET/CT, all of whom demonstrated the pathognomonic constellation of, 1) unilateral absence of scrotal testicular activity, and 2) FDG-avid nodal masses along the typical testicular lymphatic drainage pathway. These characteristic patterns were corroborated by a targeted clinical history and examination which revealed a history of cryptorchidism, and elevated β-hCG in two of three patients. All were subsequently confirmed as metastatic seminoma on biopsy and open resection.

Conclusion

These cases highlight the importance of clinical history and examination for the clinician, as well as a sound knowledge of the typical testicular lymphatic drainage pathway for the PET physician, which would assist with prompt recognition of the characteristic imaging patterns on FDG-PET/CT. It further anecdotally supports the utility of FDG-PET/CT in evaluating undiagnosed abdominopelvic masses, as well as a potential role in the initial staging of germ cell tumours in appropriately selected patients.

Current pharmacotherapy for testicular germ cell cancer

INTRODUCTION

With the implementation of platinum-based chemotherapy, germ cell tumors (GCTs) became a model for a curable solid tumor, with survival rates of 95% in all patients with >80% survival in metastatic stages.

AREAS COVERED

Herein, the authors review the current standards of adjuvant chemotherapy for stage I GCTs as well as first-line and salvage treatments for metastatic disease. Novel approaches for refractory disease are also reviewed.

EXPERT OPINION

Active surveillance should be considered for all stage I patients and is the preferred approach for stage I seminoma. In stage I non-seminomas with vascular invasion, one cycle of bleomycin, etoposide, and cisplatin (BEP) substantially reduces the relapse risk. For most advanced GCTs, BEP remains the first-line standard of care. For poor prognosis disease treatment, stratification according to tumor marker decline is recommended. The role of primary high-dose chemotherapy (HDCT) for selected very high-risk patients remains to be prospectively evaluated. Salvage HDCT at relapse seems superior to conventional chemotherapy, retrospectively. The treatment of multiply relapsed disease remains challenging. The gemcitabine/oxaliplatin/paclitaxel (GOP) protocol is considered the standard for refractory disease. However, overall, outcomes are poor and new treatment approaches are urgently needed with targeted therapies so far failing to yield relevant clinical activity.