Stage II Testicular Seminoma: Patterns of Care and Survival by Treatment Strategy

Contemporary Role of Radiation Therapy in Testicular Cancer

Testicular cancer is a rare but curable male malignancy. Seminoma represents the majority of germ cell tumors and is considered radiation sensitive. Radiation treatment plays a role in adjuvant therapy after orchiectomy of stage I, IIA, and IIB seminomas. Radiation dose de-escalation has been effective in preventing tumor recurrences while also limiting acute and long-term toxicities. However, long-term risks, including the prevailing concern of secondary malignancy risk, between adjuvant radiation and chemotherapy play a role in recommendations. Ongoing work continues to be performed to reduce radiation field and dose in combination with chemotherapy while still maintaining excellent outcomes.

Testicular cancer with small metastatic burden: optimal approach in 2024

PURPOSE OF REVIEW

Recent advancements in the management of clinical stage II (CS II) testicular cancer have transformed it into a predominantly curable condition. This success in treatment advancements has markedly extended patient survival. However, these treatments carry risks and morbidities, which is important to consider given the disease's impact on young men and the emerging understanding of long-term treatment consequences.

RECENT FINDINGS

Emerging data support primary retroperitoneal lymph node dissection (RPLND) for select CS II seminoma patients, with similar short-term outcomes to chemotherapy but less treatment intensity. Recent studies have also challenged the reflexive use of adjuvant chemotherapy for pathologic node-positive disease, as growing evidence shows low relapse rates regardless of nodal stage. Furthermore, novel biomarkers like circulating serum microRNA-371a-3p levels can help predict the presence of viable germ cell tumor at time of RPLND.

SUMMARY

Advances in risk stratification and therapy enable personalized de-escalation approaches for oligometastatic testicular cancer, optimizing survivorship. Upfront RPLND, reassessing adjuvant systemic therapy for RPLND pN+ disease, and novel biomarkers will shape precision treatment to achieve high cure rates with excellent quality of life. Ongoing trials of reduced-intensity regimens, accurate prognostic models, improved surgical strategy, and emerging biomarkers represent the next frontier in tailored curative therapy.

The prognostic impact of treatment centralization in patients with testicular germ cell tumors: analysis of hospital-based cancer registry data in Japan

BACKGROUND

To identify the prognostic impact of treatment centralization in patients with testicular germ cell tumors (TGCT).

METHODS

We used a hospital-based cancer registry data in Japan to extract seminoma and non-seminoma cases that were diagnosed in 2013, histologically confirmed, and received the first course of treatment. To compare the 5-years overall survival (OS) rates of patients stratified by institutional care volume, we performed a Cox proportional hazards regression analysis using inverse probability of treatment weighting (IPTW) method to adjust patient backgrounds.

RESULTS

A total of 1767 TGCT patients were identified. The 5-years OS rates for stage II and III TGCT patients treated at low-volume institutions (< 7 cases) were significantly worse than high-volume institutions (≥ 7 cases) (91.2% vs. 83.4%, p = 0.012). Histological stratification revealed that 5-year OS rates for stage II and III seminoma patients in the low-volume group were significantly worse than the high-volume group (93.5% vs. 84.5%, p = 0.041). Multivariate OS analysis using an IPTW-matched cohort showed that institutional care volume was an independent prognostic factor (hazard ratio 2.13 [95% confidence interval: 1.23-3.71], p = 0.0072).

CONCLUSION

Our results indicate that stage II and III TGCT patients experience lower survival rates at low-volume institutions and would benefit from treatment centralization.

Primary Retroperitoneal Lymph Node Dissection for Stage II Seminoma: Is Surgery the New Path Forward?

PURPOSE

On the basis of National Comprehensive Cancer Network guidelines, clinical stage (CS) II seminoma is treated with radiotherapy or chemotherapy. Primary retroperitoneal lymph node dissection (RPLND) demonstrated recent success as first-line therapy for RP-only disease. Our aim was to confirm surgical efficacy and evaluate recurrences after primary RPLND for CS IIA/IIB seminoma to determine if various clinical factors could predict recurrences.

PATIENTS AND METHODS

Patients who underwent primary RPLND for seminoma from 2014 to 2021 were identified. All patients had at least 6 months of follow-up. Nineteen patients were part of a clinical trial. Patients receiving adjuvant chemotherapy were excluded from Kaplan-Meier recurrence-free survival (RFS) analysis.

RESULTS

We identified 67 patients who underwent RPLND for RP-only seminoma. One patient had pN0 disease. Median follow-up time after RPLND was 22.4 months (interquartile range, 12.3-36.1 months) and 11 patients were found to have a recurrence. The 2-year RFS for RPLND-only patients without adjuvant chemotherapy was 80.2%. Patients who developed RP disease for a period > 12 months had the lowest chance of recurrence, with a 2-year RFS of 92.2%. Seven initial CS II patients were on surveillance for 3-12 months before surgery and no patients experienced recurrence. Pathologic nodal stage and high-risk factors such as tumor size > 4 cm or rete testis invasion of the orchiectomy specimen did not affect recurrence.

CONCLUSION

CS II seminoma can be treated with surgery to avoid rigors of chemotherapy or radiotherapy. Patients with delayed development of CS II disease (> 12 months) had the best surgical results. Patients may present with borderline CS II disease, and careful surveillance may avoid overtreatment. Further study on patient selection and extent of dissection remains uncertain and warrants further investigation.

Reprint of: Updates in 2022 on the staging of testicular germ cell tumors

Testicular cancer is the most common solid neoplasm of adult men between the ages of 20 and 40 years. Germ cell tumors account for 95% of all testicular tumors. The assessment of staging is essential to guide further management of patients with testicular cancer and to prognosticate cancer-related outcomes. Postradical orchiectomy treatment options, including adjuvant therapy and active surveillance, vary based on the anatomical extent of disease, serum tumor markers, pathologic diagnosis, and imaging. This review provides an update on the germ cell tumor staging system adopted by the 8th edition of the American Joint Commission on Cancer (AJCC) Staging Manual, treatment implications, risk factors, and predictors of outcomes.

Updates in 2022 on the Staging of Testicular Germ Cell Tumors

Testicular cancer is the most common solid neoplasm of adult men between the ages of 20 and 40 years. Germ cell tumors account for 95% of all testicular tumors. The assessment of staging is essential to guide further management of patients with testicular cancer and to prognosticate cancer-related outcomes. Postradical orchiectomy treatment options, including adjuvant therapy and active surveillance, vary based on the anatomical extent of disease, serum tumor markers, pathologic diagnosis, and imaging. This review provides an update on the germ cell tumor staging system adopted by the 8th edition of the American Joint Commission on Cancer (AJCC) Staging Manual, treatment implications, risk factors, and predictors of outcomes.

Therapy of clinical stage IIA and IIB seminoma: a systematic review

PURPOSE

The optimal treatment for clinical stage (CS) IIA/IIB seminomas is still controversial. We evaluated current treatment options.

METHODS

A systematic review was performed. Only randomized clinical trials and comparative studies published from January 2010 until February 2021 were included. Search items included: seminoma, CS IIA, CS IIB and therapy. Outcome parameters were relapse rate (RR), relapse-free (RFS), overall and cancer-specific survival (OS, CSS). Additionally, acute and long-term side effects including secondary malignancies (SMs) were analyzed.

RESULTS

Seven comparative studies (one prospective and six retrospective) were identified with a total of 5049 patients (CS IIA: 2840, CS IIB: 2209). The applied treatment modalities were radiotherapy (RT) (n = 3049; CS IIA: 1888, CSIIB: 1006, unknown: 155) and chemotherapy (CT) or no RT (n = 2000; CS IIA: 797, CS IIB: 1074, unknown: 129). In CS IIA, RRs ranged from 0% to 4.8% for RT and 0% for CT. Concerning CS IIB RRs of 9.5%-21.1% for RT and of 0%-14.2% for CT have been reported. 5-year OS ranged from 90 to 100%. Only two studies reported on treatment-related toxicities.

CONCLUSIONS

RT and CT are the most commonly applied treatments in CS IIA/B seminoma. In CS IIA seminomas, RRs after RT and CT are similar. However, in CS IIB, CT seems to be more effective. Survival rates of CS IIA/B seminomas are excellent. Consequently, long-term toxicities and SMs are important survivorship issues. Alternative treatment approaches, e.g., retroperitoneal lymph node dissection (RPLND) or dose-reduced sequential CT/RT are currently under prospective investigation.

When is a seminoma not a seminoma? The incidence, risk factors and management of patients with testicular seminoma with discordant elevated serum alpha-fetoprotein

OBJECTIVE

To describe the incidence, clinical and demographic factors, and treatment patterns associated with discordant elevated AFP findings in patients with pure seminomatous histology.

METHODS

We queried the National Cancer Database to identify patients with testicular GCT diagnosed in 2011-2015. Patients were grouped based on histologic diagnosis and pre-operative serum AFP level.

RESULTS

Of 18,616 patients diagnosed with testicular GCT, 53% (N=9,849) had pure seminomatous histology, of whom 8.3% (N=821) had an elevated serum AFP pre-operatively. Non-white patients with seminoma were more likely to have a pre-op elevated AFP (OR 1.42; 95% CI: 1.10-1.83); patients treated at higher volume centers were less likely to have a pre-op elevated AFP (0.66, 95% CI: 0.53-0.83). Patients with seminoma with elevated AFP received adjuvant radiation more frequently than those with NSGCT (Stage I: 15% vs 0.2%, p < 0.01; Stage II: 21.9% vs 0.1%, p <0.01) and less frequently underwent retroperitoneal lymph node dissection (RPLND) (Stage 1: 1.9% vs 11.1% p <0.01; Stage II: 8.8% vs 17.4%, p <0.01).

CONCLUSION

The detection of elevated serum alpha-fetoprotein (AFP) in patients with pure seminomatous testicular germ cell tumors (GCT) is a discordant finding that implies the presence of occult non-seminomatous GCT (NSGCT) elements. 8% of patients with pure seminomatous GCTs had diagnostically discordant elevated pre-operative AFP levels. Despite recommendations to manage these patients as NSGCT, patients with seminoma and elevated AFP were managed in a fashion comparable to those with seminoma and normal AFP levels.

Contemporary management of early stage testicular seminoma

Therapy for early stage testicular seminoma has changed radically over the past several decades. Given high cure rates and clinical trials supporting less active therapy in most cases, close observation after radical orchiectomy is now considered standard of care for clinical stage (CS) IA/IB seminoma, with either radiation therapy (RT) or chemotherapy salvage options possible. For CS IIA/IIB seminoma characterized by non-bulky retroperitoneal lymph node involvement (≤5 cm in greatest dimension), RT or combination chemotherapy are the standard of care. Given high comparable survival rates, preventing treatment-related toxicity and second malignancy, and limiting quality of life deficits associated with intense treatment has gained much greater importance. Clinical trials are currently testing the feasibility of retroperitoneal lymph node dissection (RPLND) for low volume CS IIA/IIB metastatic testicular seminoma to this end. Likewise, one cycle of chemotherapy is being evaluated as an adjuvant approach to reduce recurrence rates in CS I disease with unfavorable risk factors. Moreover, recent genomic and molecular studies have recently identified novel signatures and a potential biomarker for testicular seminoma. In this review, we first summarize the evolution of early stage seminoma management and discuss the effectiveness and drawbacks of contemporary treatment strategies. We further outline future perspectives and potential challenges in management of early stage testicular seminoma.

Systemic therapy for primary and extragonadal germ cell tumors: prognosis and nuances of treatment

Testicular germ cell tumors are the most common solid tumors in young men. These cancers represent a success story of modern medicine in our ability to cure young patients and offer decades of life, with a 5-year survival rate of approximately 95%. This review outlines the staging and risk classification of testicular cancers, and reviews the current state of knowledge and standard of care for the systemic treatment of testicular germ cell tumors with chemotherapy, focusing on the relevant clinical data supporting each treatment regimen. This review also briefly highlights current areas of active investigation, notably in the relapsed and refractory setting, including ongoing clinical trials.

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.

Primary tumor size thresholds in stage IA testicular seminoma: Implications for adjuvant therapy after orchiectomy and survival

OBJECTIVES

Primary tumor size (PTS) is the main prognostic factor for relapse in clinical stage (CS) IA testicular seminoma (T1N0M0S0) and the 8th edition of the Tumor-Node-Metastasis staging system now subcategorizes pT1 tumors into pT1a and pT1b based on PTS (<3 cm and ≥3 cm, respectively). We attempted to assess PTS as a prognosticator for overall survival (OS) in CS IA seminoma and to evaluate the comparative effectiveness of active surveillance (AS) versus adjuvant therapy (AT) in patients with large primary tumors (LPT).

METHODS AND MATERIALS

In the National Cancer Database (2004-2014), 2455 (47.7%) and 2685 (52.3%) patients with CS IA seminoma were treated with AS and AT, respectively. AT was defined as the receipt of chemotherapy or radiation within 3 months after orchiectomy. A cut-point analysis was performed to determine the optimal PTS threshold predicting OS at 5 years after orchiectomy. Inverse-probability of treatment weighting (IPTW)-adjusted Kaplan-Meier curves and Cox regression analyses were used to compare OS of patients with LPT (using the optimal PTS cut-point) treated with AS versus AT.

RESULTS

In adjusted analysis, pathologic T-stage (pT1a vs. pT1b) did not predict OS and no OS benefit was noted in pT1b patients treated with AT. The optimal PTS cut-point was 4.5 cm. In multivariable analysis, patients with LPT (≥4.5 cm) had an increased risk of overall mortality (HR = 1.87, P = 0.003). Kaplan-Meier curves revealed that OS was superior in patients with LPT treated with AT (IPTW-adjusted log-rank P = 0.029). In IPTW-adjusted Cox regression analysis, AT was associated with an OS benefit in patients with LPT (HR = 0.59, 95%CI: 0.39-0.91, P = 0.017).

CONCLUSIONS

In this National Cancer Database analysis, PTS was a predictor of OS in CS IA seminoma. An OS benefit was noted for individuals with LPT (defined as PTS ≥4.5 cm) managed with AT. These findings may warrant refinement of Tumor-Node-Metastasis staging system.

Clinical characteristics of testicular seminoma in individuals in West China: a 10-year follow-up study

Objective

To assess the clinical characteristics of testicular seminoma (TS).

Patients and methods

A testicular cancer (TC) survey was conducted by the Department of Urology, West China Hospital, between 2008 and 2018. Tumors were classified according to the NCCN criteria such as age, tumor size, tumor marker levels, histopathology, clinical stage, initial treatment, follow-up, and clinical outcomes, were obtained from the database of our center.

Results

Among 155 registered cases of TC with seminomatous element, 127 cases of pure TS were analyzed. All 127 patients with a median age of 37 years were pathologically diagnosed with orchiectomy specimens. Orchiectomy, chemotherapy, and radiotherapy were the main treatments for these patients. Patients with clinical stages I, II, and III testicular cancer of accounted for 81.1% (n=103), 15.7% (n=20), and 3.2% (n=4) of all patients, respectively. After a median follow-up time of 50 months, five patients presented with relapse during follow-up, and one among them died. Of the patients with stage I TS (T1N0M0S0 CS IA), three patients who only underwent orchiectomy relapsed. Among patients with stage II TS (T1N1M0S1 CS IIA), one patient relapsed after orchiectomy, post-surgery chemotherapy and radiotherapy. In four patients with stage III disease (T2N1M1aS1 CS IIIA), one relapsed after orchiectomy and chemotherapy, and died shortly after salvage chemotherapy and radiotherapy due to recurrence. The median overall survival time was 50 months. In all patients, the 2-year overall survival and progression-free survival probabilitis were 98.6% and 98.8%, respectively.

Conclusion

The present study shows that patients with TS have good prognosis even at an advanced stage. Surveillance after orchiectomy was important for patients with CSI seminoma, and we recommend cisplatin-based chemotherapy as salvage therapy for patients with CSI seminoma. In addition, patients with a maximal tumor diameter >4 cm should undergo post-surgery chemotherapy.

[Management of metastatic testicular germ cell tumors]

Metastatic testicular germ cell tumors are rare entities with a high cure rate owing to their major chemosensitivity. Current guidelines should be strictly followed to ensure maximal cure rate. Germ cell tumor treatment requires multidisciplinary skills and is based on cisplatin-based chemotherapy. The current challenge for these patients with favorable prognosis is to limit over- or under-treatment. Centralization of care for patients with these rare cancers is a key point to achieve the best chance of cure.

Management of Stage II Germ Cell Tumors

There are several treatment approaches for stage II germ cell tumors (GCTs), and a thorough understanding of the staging classification and histologic differences in tumor biology and therapeutic responsiveness is critical to determine an effective, multimodal management strategy that involves urologists, medical oncologists, and radiation oncologists. This article discusses contemporary management strategies for stage II GCTs, including chemotherapy, radiotherapy, retroperitoneal lymph node dissection (RPLND), and surveillance. Patient selection, histology, and extent of lymphadenopathy drive management, and, as both treatment and detection strategies continue to emerge and be refined, the management of patients with stage II GCT continues to evolve.

Update on epidemiologic considerations and treatment trends in testicular cancer

PURPOSE OF REVIEW

We aim to give an overview of the epidemiology and treatment trends of testicular germ cell tumors (TGCTs), with an emphasis on recent trends.

RECENT FINDINGS

The incidence of TGCT appears to be increasing, particularly in developed countries, although the reasons are not well understood. There is evidence of racial differences in predisposition to TGCT, with white men having highest risk and men of African or Asian descent having lower risk. In the United States, the incidence of TGCT among Hispanics appears to be rising most quickly. A recent genomic analysis indicates there is no highly penetrant major TGCT susceptibility gene. Incorporation of multidisciplinary care has led to excellent long-term cure rates; however, access to care and insurance remains barriers in young men. Recent treatment trends have centered on maximizing oncologic outcomes while minimizing long-term morbidity.

SUMMARY

Emerging population-level data provide critical insight into the evolving demographics of TGCT, which may allow for elucidation of biologic and environmental determinants of TGCT. Further, identification of socioeconomic barriers to excellent clinical outcomes will allow for targeted interventions to patients with unique demographic and socioeconomic considerations. Treatment trend analyses suggest that the field is moving toward minimizing treatment-related morbidity.

Reclassification of good-risk seminoma: prognostic factors, novel biomarkers and implications for clinical management

Germ cell tumors represent 11% of the cancers diagnosed in adolescent males and are the most common solid tumors in adult men between the ages of 20 and 35. Pure seminoma accounts for around 50% of all testicular germ cell tumors. The prognostic classification of the International Germ Cell Cancer Collaborative Group for good-prognosis seminoma includes both nodal disease and pulmonary visceral metastases. In this article, we analyzed recent data on prognosis and outcome of good-prognosis seminoma to revise the traditional classification of the disease and improve tailored treatment.

Clinical Stage IIA-IIC Seminoma: Radiation Therapy versus Systemic Chemotherapy versus Retroperitoneal Lymph Node Dissection

BACKGROUND

Clinical stage II (CSII) seminoma is defined by the presence of pure seminoma accompanied by retroperitoneal lymph node metastases. In patients with bulky disease (lymph nodes > 5 cm in diameter), platinum-based chemotherapy is the widely accepted standard of care. However, the optimal choice of treatment for CSIIA and IIB is more controversial.

METHODS

We performed a PubMed search using the key words stage II seminoma, BEP (cisplatin, etoposide, and bleomycin), hockey-stick radiotherapy, dog-leg radiotherapy and retroperitoneal lymph node dissection. Most relevant publications were summarized for this review.

RESULTS

To date, no randomized trials have prospectively compared radiotherapy (RT), chemotherapy (CT) and retroperitoneal lymph node dissection (RLND) for CSII seminoma. Because of the predominantly retrospective analyses and only few prospective trials data interpretation is complex. In CSIIA with lymph nodes of < 2 cm, RT and CT seem to be equally effective, while in CSIIB, a decreased number of relapses were observed in CT-treated patients. In addition, RT seems to be associated with a higher incidence of long-term sequelae when compared with CT.

CONCLUSION

Prospective clinical trials are needed to systematically compare the different treatment modalities. De-escalation of treatment intensity without loss of efficacy is required to improve long-term outcome for this young patient population.

Radiotherapy in testicular germ cell tumours - a literature review

Testicular germ cell tumours (GCT) represent about 1-2% of malignant in men. The essential therapeutic option for early-stage GCT is radical orchiectomy (RO), except in situations that require immediate chemotherapy in patients with a massive dissemination and unequivocally elevated levels of tumour markers. Postoperative radiotherapy (PORT) in patients with testicular seminoma in Clinical Stage I (CS I) is one of the treatment options next to active surveillance (AS) and chemotherapy (CHTH). Regardless of the procedure, five-year survival in this group of patients ranges between 97% and 100%. In the article, we present the literature review pertinent to therapeutic options, with a focus on radiotherapy. We have searched MEDLINE (PubMed) for all studies on patients with GCT treated with radiation therapy during the last 20 years, and the current therapeutic recommendations. We used the following keywords: germ cell tumours, testis, seminoma, non-seminoma, radiotherapy, outcome.

Patterns of care and survival outcomes for adolescent and young adult patients with testicular seminoma in the United States: A National Cancer Database analysis

INTRODUCTION

Testicular germ cell tumors (GCTs) are the most common solid tumor among adolescent and young adult (AYA) males. AYA patients with GCTs most typically have non-seminoma compared with seminoma, and accordingly there are fewer data reported on the AYA experience with testicular seminoma.

OBJECTIVE

To evaluate national trends in postoperative treatment and overall survival (OS) outcomes in testicular seminoma by age group, specifically comparing AYAs with older adults.

STUDY DESIGN

The National Cancer Data Base (NCDB) was queried for patients with testicular seminoma diagnosed between 2004 and 2012, who underwent orchiectomy followed by observation or adjuvant therapy (chemotherapy, radiation (RT), or both). Patients were grouped by age: AYA (15-39 years), adults between 40 and 55 years, and adults >55 years. Overall survival (OS) was presented using Kaplan-Meier curves and groups compared via a log-rank test. Univariate (UVA) and multivariate (MVA) analyses were performed using Cox proportional hazards regression models. Binary multiple logistic regression identified differences in variables by age category.

RESULTS

Of the total 22,361 patients the majority were AYAs (12,880, 57.6%), followed by adults 40-55 years (8,022, 35.9%), and >55 years (1,459, 6.5%). Unadjusted 5-year OS was significantly better for AYAs versus adults 40-55 years and >55 years (98.0%, 96.4%, 87.7%; p < 0.001), as was 10-year OS (96.1%, 91.8%, 71.3% respectively; p < 0.001). The Table shows that on a MVA, OS was significantly better for AYAs versus adults 40-55 years and adults >55 years. AYA patients were also more commonly treated at centers with greater clinical volume. Additionally, AYA patients were less likely to present with metastatic disease. Accordingly, AYA patients were less likely to undergo retroperitoneal lymph node dissection (OR 0.81; p = 0.001) and were less often managed with adjuvant therapy including chemotherapy (OR 0.91; p = 0.027), RT (OR 0.93; p = 0.025), or both (OR 0.68; p = 0.020).

DISCUSSION

AYA patients with testicular seminoma present with earlier stage disease and in the clinical Stage I setting are more often are managed with active surveillance following orchiectomy when compared with older adults in this population-based analysis. Among AYA patients, OS was modestly better when compared with adults 40-55 years and significantly better when compared with adults >55 years.

CONCLUSION

Our objective to describe the patterns of care and survival outcomes for AYA patients with testicular seminoma in the USA was met by reviewing this large national dataset. These results may inform future guidelines for management of AYA seminoma.

Radiotherapy for stage I and II testicular seminomas: Secondary malignancies and survival

INTRODUCTION

Testicular seminoma affects relatively young men with excellent survival outcomes. There has been increasing concern that radiotherapy (RT) leads to secondary malignant neoplasms (SMNs) and subsequent mortality. We evaluated the effect of RT on incidence of SMNs and quantified cancer-related mortality and other causes of death for patients with stage I and II testicular seminoma.

MATERIAL AND METHODS

A national sample of men (1988-2013) diagnosed with stage IA/IB/IS/IIA/IIB/IIC testicular seminomas from Surveillance, Epidemiology, and End Results were evaluated. Use of RT over time and survival curves (5/10/15-year) was stratified by stage. Log-binomial regression determined relative risk of developing SMNs. Incidence rate ratios (IRR) and age-adjusted Cox proportional hazards models compared overall, cancer-specific survival (CSS), and other cancer-specific survival. Competing-risks regression generated cumulative incidence functions. Prevalence ratios explored excess deaths owing to specific causes.

RESULTS

A total of 16,463 men were included with 9,126 (55.4%) undergoing RT with markedly decreased use for stage I seminoma in recent years (<20%) and ~50% for stage IIA. RT increased risk of SMNs (relative risk = 1.84 [95% CI: 1.61-2.10, P<0.01]). Survival rates were excellent (15-year CSS for stage I [≥99%], stage IIA [98.1%], stage IIB-C [96%-97%]). RT was associated with improved CSS for stage IB and IIA, but demonstrated less benefit for stage IA (IRR = 0.63 [95% CI: 0.35-1.14, P = 0.10]) with worse other cancer-specific survival (IRR = 1.80 [95% CI: 0.97-3.59, P = 0.05]). Gastrointestinal, respiratory, urinary, and hematologic malignances accounted for 84% of SMN deaths.

CONCLUSIONS

RT offers excellent CSS for men with stage I/II seminoma and an increased risk of SMN later in life. Future studies should better evaluate risk-stratification for stage IB patients.