Rates of teratoma and viable cancer at post-chemotherapy retroperitoneal lymph node dissection after induction chemotherapy for good risk nonseminomatous germ cell tumors

Resection of Residual Masses After Chemotherapy for Metastatic Nonseminomatous Germ Cell Tumors in Adolescents and Adults

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors' suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in the Journal of Clinical Oncology, to patients seen in their own clinical practice.Optimal treatment of patients with testicular germ cell tumors requires a coordinated multidisciplinary approach, so that surgery, chemotherapy, and, when appropriate, radiation therapy can be integrated into a coherent and comprehensive treatment plan. Nonseminomatous germ cell tumors (NSGCT) are often a mixture of teratoma and cancer (choriocarcinoma, embryonal carcinoma, seminoma, and/or yolk sac tumor). While the cancers are highly sensitive to and often cured by chemotherapy, teratoma is resistant to chemotherapy and radiation therapy and generally must be resected surgically to be successfully treated. Therefore, the standard of care for metastatic NSGCT is to resect all resectable residual masses after chemotherapy. If such resection reveals only teratoma and/or necrosis/fibrosis, then patients are put on a surveillance schedule to monitor for relapse. If viable cancer is found and there are positive margins or 10% or more of any of the residual masses consists of viable cancer, then two cycles of adjuvant chemotherapy should be considered.

Advanced germ cell tumor patients undergoing post-chemotherapy retroperitoneal lymph node dissection: Impact of residual teratoma on prognosis

OBJECTIVES

To evaluate the histologic findings and clinical outcomes of post-chemotherapy retroperitoneal lymph node dissection for advanced germ cell tumor.

METHODS

We analyzed the medical records of 66 patients who underwent post-chemotherapy retroperitoneal lymph node dissection between 2005 and 2019 at Tsukuba University Hospital.

RESULTS

The proportions of necrosis, teratoma, and viable germ cell tumor in the specimens were 62.1%, 36.4%, and 1.5%, respectively. The 5-year progression-free and overall survival rates were 82.3% and 91.3%, respectively. The 5-year overall survival rate of patients with residual teratoma was significantly worse than that of patients with necrosis only (74.1% vs 100%). Overall, three patients died: one from cancer and two from teratoma with somatic-type malignancy. Of these, two patients relapsed after incomplete resection of residual teratoma. When limited to patients with completely resected teratoma, the 5-year overall survival rate was 91.7%, which did not differ from that for patients with necrosis only. Multivariate analysis showed that presence of teratoma in the primary site and decrease in retroperitoneal lymph node mass to less than 50% of the initial tumor size were independent factors for residual teratoma. However, the absence of these factors could not reliably predict necrosis only in retroperitoneal lymph node dissection specimens.

CONCLUSIONS

In our series, 98% of post-chemotherapy retroperitoneal lymph node dissection pathology was either necrosis or teratoma, with viable germ cell tumor only found in 2% of patients. Residual teratoma was associated with poorer prognosis, especially in cases of incomplete resection.

Robotic retroperitoneal lymph node dissection for primary and post-chemotherapy testis cancer

The role of retroperitoneal lymph node dissection (RPLND) in testicular cancer is well established in both the primary and post-chemotherapy setting. The aim of this study was to report our 2 years oncological outcomes of robotic RPLND. A retrospective review was performed of all patients undergoing robotic RPLND by a single surgeon at Princess Margaret Cancer Centre. Demographic, perioperative, and oncologic data were analyzed using descriptive statistics. Between September 2014 and June 2020, 141 patients underwent an RPLND [33 (23.4%) were primary, 108 (76.6%) were post-chemotherapy]. 27 (19.1%) patients underwent a robotic bilateral template nerve-sparing RPLND. RPLND indication was primary (i.e. pre-chemotherapy) in 18 (66.7%), and post-chemotherapy in 9 (33.3%) patients. Stage at RPLND was 2A (n = 15, 55.6%), 2B (n = 9, 33.3%), 2C (n = 1, 3.7%) and 3 (n = 2, 7.4%). Median OR time (incision to closure) was 525 min and blood loss was 200 ml. Nerve sparing was performed in all but one case. Six (22.2%) adjuvant procedures were performed including two (7.4%) vascular repairs. Median length of stay was 2 days. Viable tumor was detected in 17 (63%) and teratoma in 9 (33.3%). Median follow-up was 31.3 months. No adjuvant chemotherapy was given. Three patients (11.1%) relapsed: 2 out-of-field and 1 with both in-field and out-of-field disease. Robotic RPLND can be performed safely. Long-term follow-up of series such as ours, enriched with patients with viable disease and/or teratoma, and not treated with adjuvant chemotherapy is required to ensure oncological outcomes are comparable to the open approach.

Four Cycles of Etoposide plus Cisplatin for Patients with Good-Risk Advanced Germ Cell Tumors

Background

The National Comprehensive Cancer Network recommends either three cycles of bleomycin, etoposide, and cisplatin or four cycles of etoposide and cisplatin (EPx4) as initial chemotherapy for the treatment of good‐risk germ cell tumors (GCTs). To assess the response, toxicity, and survival outcomes of EPx4, we analyzed our experience.

Material and Methods

Response and survival outcomes, selected toxicities, and adherence to chemotherapy dose and schedule were assessed in patients with good‐risk GCT who received EPx4 at Memorial Sloan Kettering Cancer Center between 1982 and 2016. The results were compared with our past results and published data.

Results

Between 1982 and 2016, 944 patients with GCT were treated with EPx4, 289 who were previously reported plus 655 treated between January 2000 and August 2016. A favorable response was achieved in 928 of 944 patients (98.3%). Five‐year progression‐free, disease‐specific, and overall survival rates were 93.9%, 98.6%, and 97.9%, respectively. Median follow‐up was 7.3 years (range, 2.8 months to 35.5 years). Viable, nonteratomatous malignant GCT was present in 3.5% of 432 postchemotherapy retroperitoneal lymph node dissection specimens from patients with nonseminomatous GCT. Febrile neutropenia and thromboembolic events occurred in 16.0% and 8.9%, respectively, with one treatment‐related death. In the more recent 655‐patient cohort, full‐dose EPx4 was administered to 631 (96.3%), with deviations from planned treatment driven mainly by vascular (n = 13), hematologic (n = 11), renal (n = 7), or infectious (n = 5) events.

Conclusion

EPx4 is highly effective and well tolerated in patients with good‐risk GCTs and remains a standard of care.

Implications for Practice

Four cycles of etoposide and cisplatin (EPx4) is a standard‐of‐care regimen for all patients with good‐risk germ cell tumors with a favorable response rate and disease‐specific survival of 98%. Full‐dose administration of etoposide and cisplatin and complete resection of residual disease lead to optimal outcomes. EPx4 should be the recommended regimen in active smokers, patients with reduced or borderline kidney function, and patients aged 50 years or older, which are patient groups at increased risk for bleomycin pulmonary toxicity. Because of a risk of acquired severe pulmonary illness, EPx4 may also be favored for patients who vape or use e‐cigarettes and during ongoing transmission of severe acute respiratory syndrome coronavirus 2.

The NCCN recommends either three cycles of bleomycin, etoposide, and cisplatin (BEPx3) or four cycles of etoposide and cisplatin (EPx4) as initial chemotherapy for the treatment of good‐risk germ cell tumors. This article assesses outcomes specific to EPx4 treatment.

Considerations When Treating Patients with Good-risk Germ Cell Tumors

Three cycles of bleomycin, etoposide, and cisplatin or four cycles of etoposide and cisplatin are options for patients with good-risk germ cell tumors. Despite no significant differences in clinical outcomes in a randomized trial, studies suggest variable impact on postchemotherapy retroperitoneal lymph node dissection histology, which may help inform treatment decisions.

Management of Residual Mass in Germ Cell Tumors After Chemotherapy

PURPOSE OF REVIEW

The purpose of this review is to educate medical oncologists on the management of patients with residual germ cell tumors and the role of surgical resection after platinum-based chemotherapy.

RECENT FINDINGS

Patients with non-seminomatous testicular cancer and residual enlarged retroperitoneal lymph nodes > 1 cm following induction chemotherapy with normal tumor markers should undergo a post-chemotherapy retroperitoneal lymph node dissection. All patients with primary mediastinal non-seminoma should undergo surgical resection of the mediastinal mass post-chemotherapy. These are complex surgeries and require expert surgeons in high-volume centers. Patients with advanced testicular seminoma who have residual masses less than 3 cm after chemotherapy can be observed without further intervention. Patients with a residual mass > 3 cm should be evaluated with PET scan after 6 weeks of chemotherapy. Residual mass with negative PET scan can be followed by surveillance while a positive PET scan requires further work up to rule out active disease.

Testicular teratomas: a growing problem?

Testicular teratomas represent a specific entity within the group of germ-cell tumours. They may comprise elements of all three germ layers. In contrast to prepubertal benign teratomas observed in infants and adolescents, postpubertal teratomas originate from the malignant germ-cell precursor. Given the good prognosis and curability of most patients with germ-cell tumour, medical oncologists and urological surgeons must be well acquainted with the principles of teratomas management. Surgery plays the decisive part in teratomas treatment, as these tumours are resistant to radio- and, to some extent, chemotherapy. In this article we concentrate on the management of post-chemotherapy resection of teratomatous masses, with special attention to the phenomenon of 'growing teratoma syndrome' and somatic-type transformation of teratomas. To understand the nature of teratomas better, we begin with a glimpse of their biological, molecular and immunohistochemical features. Managing germ-cell tumours, teratomas in particular, in high-volume reference centres is of utmost importance to maintain and increase the survivorship rate in these patients.

[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.

Detailed pathologic analysis on the co-occurrence of non-seminomatous germ cell tumor subtypes in matched orchiectomy and retroperitoneal lymph node dissections

The frequency of co-occurrence between germ cell tumor (GCT) components in non-seminomatous germ cell tumor (NSGCT) orchiectomy specimens and their correlation with histologic findings in subsequent retroperitoneal lymph node dissection (RPLND) specimens have not been well characterized. The objective of the study was to report the first detailed clinicopathologic analysis of NSGCT orchiectomy and RPLND samples to determine the likelihood and agreement of the co-occurrence of GCT components. A total of 118 consecutive patients with NSGCT treated between 1988 and 2012 who underwent both orchiectomy and RPLND at a single academic tertiary care center were analyzed. Statistical analysis of co-occurrence likelihood and agreement of GCT components was performed, both within and between orchiectomy and RPLND specimens. Embryonal carcinoma was the most frequent component present in orchiectomy specimens, and there were multiple significant associations between orchiectomy GCT components; seminoma occurred less frequently with embryonal carcinoma (OR 0.29 [95% confidence interval (CI) 0.11-0.75]; p < 0.01), and teratoma more frequently occurred with choriocarcinoma (OR 9.64 [95% CI 1.22-76.12]; p = 0.01). Presence of teratoma in the orchiectomy specimen predicted for a fourfold increase in distant metastasis on multivariate analysis (HR 4.92 [1.14-18.9]; p = 0.02). The only significant association of co-occurrence in the RPLND specimen was between embryonal carcinoma and teratoma (OR 0.01 [95% CI 0-0.07]; p < 0.001), where it was significantly less likely for them to occur together. Our findings are limited by their retrospective nature. The co-occurrence of GCT components within orchiectomy specimens does not appear to be a completely random process. However, there is less agreement and more randomness between the occurrence of the GCT components in matched orchiectomy and RPLND samples. In this report, we look at the co-occurrence of different GCT components within matched orchiectomy and RPLND pathology specimens and show that co-occurrence is not a completely random process.