Teratomatous Elements in Orchiectomy Specimens Are Associated with a Reduced Relapse-Free Survival in Metastasized Testicular Germ Cell Tumors

Oncologic outcomes of retroperitoneal lymph node dissection following first-line chemotherapy for metastatic non-seminomatous germ-cell tumors

BACKGROUND

Post-chemotherapy retroperitoneal lymph node dissection (pcRPLND) is integral to multimodal treatment of patients with metastatic non-seminomatous germ-cell tumors (NSGCT). We review pathologic and long-term outcomes of pcRPLND following first-line chemotherapy with a focus on residual mass size and primary tumor histology. Our goal was to identify new predictive approaches that can refine surgical indications.

PATIENTS AND METHODS

Patients who underwent pcRPLND for NSGCT at our institution between 1 January 2000 and 18 January 2023 following first-line chemotherapy were included. The primary outcome was surgical pathology categorized as (i) viable non-teratomatous germ-cell tumor (GCT) (with or without teratoma), (ii) teratoma only, or (iii) fibrosis/necrosis stratified by largest residual mass size. Secondary outcomes included 10-year relapse-free survival, disease-specific survival, and overall survival.

RESULTS

Of 1027 eligible patients, 45% had teratoma and 4% had viable non-teratomatous GCT found at pcRPLND. With a median follow-up of 5.2 years, there was one isolated retroperitoneal relapse and 26 GCT-related deaths. As the residual mass size increased, the likelihood of teratoma in the pcRPLND specimen increased from ∼20% (residual masses <1 cm) to ∼70% (>5 cm). The risk of viable non-teratomatous GCT similarly increased from ∼2% up to ∼10%. Ten-year relapse-free and overall survival worsened with increasing mass size. Adjusting for risk group, clinical stage, residual mass size, and lymphovascular invasion at orchiectomy, the presence of yolk sac tumor [odds ratio (OR) 1.86, 95% confidence interval (CI) 1.35-2.56] and teratoma in the orchiectomy specimen (OR 3.09, 95% CI 2.27-4.23) were each independently associated with finding teratoma or viable non-teratomatous GCT at pcRPLND.

CONCLUSIONS

Following first-line chemotherapy, pcRPLND provides effective control of the retroperitoneum with few relapses and GCT-related deaths. Guideline recommendations for or against pcRPLND based on residual mass size alone should be revisited due to the significant association of orchiectomy histology with pcRPLND pathology and the benefits surgical consolidation has on disease control and survival.

Long-term Relapse and Survival in Clinical Stage I Testicular Teratoma

BACKGROUND AND OBJECTIVE

Studies in metastatic nonseminomatous germ-cell tumor (NSGCT) suggest that the presence of teratomatous elements in the primary tumor is a risk factor for poor survival. Many guidelines have extrapolated this observation and recommend adjuvant retroperitoneal lymph-node dissection (RPLND) even for clinical stage I (CSI) teratoma confined to the testicle. Our objective was to assess relapse-free survival (RFS), cancer-specific survival (CSS), overall survival (OS) among patients with CSI pure teratoma in comparison to CSI NSGCT.

METHODS

Patients with CSI NSGCT managed with surveillance between 1980 and 2023 were identified in the prospectively maintained Princess Margaret Cancer Centre database. We compared cases with pure teratoma with or without somatic transformation in the primary tumor to all other nonteratomatous NSGCTs.

KEY FINDINGS AND LIMITATIONS

A total of 774 patients with CSI NSGCT were identified, including 63 (8.1%) with pure teratoma and/or somatic transformation in the primary tumor. Median follow-up was 61 mo. The pure teratoma group had superior RFS at 6 yr (85.2% vs 67.9%; p = 0.008). There were no significant differences in 6-yr CSS (100% vs 99.1%; p = 0.92) or OS (97.4% vs 98.1%; p = 0.33). Limitations include the single-center setting and the limited follow-up (median 61 mo), hindering the ability to detect late relapses.

CONCLUSIONS AND CLINICAL IMPLICATIONS

CSI pure teratoma managed with surveillance is associated with a low risk of relapse overall and significantly lower risk of relapse in comparison to other CSI NSGCTs. No patients with CSI teratoma in the study population died of testicular cancer. Guidelines should be revised to include surveillance as a preferred approach for CSI teratoma.

PATIENT SUMMARY

We compared survival rates after testicle removal in clinical stage I testicular cancer for two different tumor types. We found that cancer-specific and overall survival rates were similar for pure teratoma tumors and nonseminoma tumors, and that the recurrence rate was lower for pure teratoma tumors. Our results support surveillance as a suitable option after surgery for patients with clinical stage I testicular teratoma.

Impact of teratoma on survival probabilities of patients with metastatic non-seminomatous germ cell cancer: Results from the IGCCCG Update Consortium

AIMS

To resolve the ongoing controversy surrounding the impact of teratoma (TER) in the primary among patients with metastatic testicular non-seminomatous germ-cell tumours (NSGCT).

PATIENTS AND METHODS

Using the International Germ Cell Cancer Collaborative Group (IGCCCG) Update Consortium database, we compared the survival probabilities of patients with metastatic testicular GCT with TER (TER) or without TER (NTER) in their primaries corrected for known prognostic factors. Progression-free survival (5y-PFS) and overall survival at 5 years (5y-OS) were estimated by the Kaplan-Meier method.

RESULTS

Among 6792 patients with metastatic testicular NSGCT, 3224 (47%) had TER in their primary, and 3568 (53%) did not. In the IGCCCG good prognosis group, the 5y-PFS was 87.8% in TER versus 92.0% in NTER patients (p = 0.0001), the respective 5y-OS were 94.5% versus 96.5% (p = 0.0032). The corresponding figures in the intermediate prognosis group were 5y-PFS 76.9% versus 81.6% (p = 0.0432) in TER and NTER and 5y-OS 90.4% versus 90.9% (p = 0.8514), respectively. In the poor prognosis group, there was no difference, neither in 5y-PFS [54.3% in TER patients versus 55.4% (p = 0.7472) in NTER], nor in 5y-OS [69.4% versus 67.7% (p = 0.3841)]. NSGCT patients with TER had more residual masses (65.3% versus 51.7%, p < 0.0001), and therefore received post-chemotherapy surgery more frequently than NTER patients (46.8% versus 32.0%, p < 0.0001).

CONCLUSION

Teratoma in the primary tumour of patients with metastatic NSGCT negatively impacts on survival in the good and intermediate, but not in the poor IGCCCG prognostic groups.