Surveillance alone in stage I malignant ovarian germ cell tumors: a MITO (Multicenter Italian Trials in Ovarian cancer) prospective observational study

OBJECTIVE

The aim of this study was to analyze the oncological outcome of stage I malignant ovarian germ cell tumors patients included in the MITO-9 study to identify those who might be recommended routine surveillance alone after complete surgical staging.

METHODS

MITO-9 was a prospective observational study analyzing data collected between January 2013 and December 2019. Three groups were identified: group A included 13 patients stage IA dysgerminoma and IAG1 immature teratoma; group B included 29 patients with stage IB-C dysgerminomas, IA-C G2-G3 immature teratomas and stage IA mixed malignant ovarian germ cell tumors and yolk sac tumors; and group C included five patients (two patients with stage IC1 and one patient with stage IC2 yolk sac tumors and two patients with mixed-stage IC2 malignant ovarian germ cell tumors).

RESULTS

A total of 47 patients with stage I conservatively treated malignant ovarian germ cell tumors were analyzed. Two patients in group B were excluded from the routine surveillance alone group due to positive surgical restaging. Therefore, a total of 45 patients were included in the study. Median follow-up was 46.2 months (range; 6-83). In total, 14 of 45 patients (31.1%) received chemotherapy, while 31 (68.9%%) underwent surveillance alone. One patient in group A, with stage IA dysgerminoma had a relapse, successfully managed with conservative surgery and chemotherapy. None of the patients in group B and C relapsed. All patients were alive at completion of the study. Overall, among 31 patients (68.9%) who underwent surveillance alone, only one patient relapsed but was treated successfully.

CONCLUSIONS

Our data showed that close surveillance alone could be an alternative option to avoid adjuvant chemotherapy in properly staged IB-C dysgerminomas, IA-IC G2-G3 immature teratomas, and IA mixed malignant ovarian germ cell tumors with yolk sac tumor component.

Can we replace adjuvant chemotherapy with surveillance for stage IA-C immature ovarian teratomas of any grade? an international multicenter analysis

BACKGROUND

The role of surveillance after surgery for stage IA-C grade 2 (G2) or grade 3 (G3) immature teratomas (ITs) is controversial with many guidelines advocating adjuvant chemotherapy. Here, we investigate the safety of surveillance in stage IA-C G1-3 ITs.

METHODS

Clinicopathological data were analysed on postpubertal patients with stage I pure ITs in Multicenter Italian Trials in Ovarian Cancer centres and at Charing Cross Hospital, UK, between January 1985 and January 2018.

RESULTS

Of 108 stage I patients, 66 (61.1%), 3 (2.8%) and 39 (36.1%) were International Federation of Gynecology and Obstetrics IA, IB, IC, respectively, with 31 (28.7%), 41 (38%) and 36 (33.3%) having grade 1 (G1), 2 and 3 disease, respectively. After surgery, 27 patients (25%) had adjuvant chemotherapy and 81 (75%) surveillance. There was no significant increase in the risk of malignant (G2-3 IT) relapse (9/81 vs 2/27; p = 0.72) or in disease-free survival (DFS) or overall survival in the surveillance vs chemotherapy groups. The median time to relapse was 17.8 months (range: 3-47) with no significant difference between surveillance or chemotherapy groups. The median follow-up was 64.3 months (Interquartile range (IQR) 22.2-101.7). Chemotherapy induced cures in all except for one patient who did not follow the surveillance protocol due to pregnancy and died of disease. Univariate and multivariate analyses revealed that only tumour grade (hazard ratio [HR] = 3.11; p = 0.02) and complete surgical staging (HR = 0.2; p = 0.01) were independent prognostic factors for decreased DFS.

CONCLUSION

The present study suggests that in the adult setting careful surveillance appears to be an acceptable alternative to adjuvant chemotherapy for stage IA-C ITs of any grade, properly staged and with negative postoperative tumour markers.

A multicentre retrospective cohort study of ovarian germ cell tumours: Evidence for chemotherapy de-escalation and alignment of paediatric and adult practice

BACKGROUND

Adult guidelines recommend BEP (bleomycin, etoposide, cisplatin) for all ovarian germ cell tumours, causing debilitating toxicities in young patients who will survive long term. Paediatricians successfully reduce toxicities by using lower bleomycin doses and substituting carboplatin for cisplatin, while testicular and paediatric immature teratomas (ITs) are safely managed with surgery alone.

AIM

The aim was to determine whether reduced-toxicity treatment could rationally be extended to patients older than 18 years.

METHODS

Multicentre cohort study was carried out in four large UK cancer centres over 12 years.

RESULTS

One hundred thirty-eight patients were enrolled. Overall survival was 93%, and event-free survival (EFS) was 72%. Neoadjuvant/adjuvant chemotherapy (82% BEP) caused 27 potentially chronic toxicities, and one patient subsequently died from acute lymphoblastic leukaemia. There was no difference in histology, stage or grade in patients ≤/>18 years, and EFS was not different in these age groups (≤18:28% and >18:28%; log-rank P = 0.96). Histological subtype powerfully predicted EFS (log-rank P = 4.9 × 10-7). Neoadjuvant/adjuvant chemotherapy reduced future relapse/progression in dysgerminoma (n = 37, chemo:0% vs. no chemo:20%), yolk sac tumour (n = 23, 26.3% vs.75%) and mixed germ cell tumour (n = 32, 40%vs.70%) but not in IT (n = 42, 33% vs.15%). Additionally, we observed no radiological responses to chemotherapy in ITs, pathological IT grade did not predict EFS (univariate hazard ratio 0.82, 95% confidence interval: 0.57-1.19, P = 0.94) and there were no deaths in this subtype.

CONCLUSION

Survival was excellent but chemotherapy toxicities were severe, implying significant overtreatment. Our data support the extension of reduced-toxicity, paediatric regimens to adults. Our practice-changing findings that IT was chemotherapy resistant and pathological grade uninformative strongly endorse exclusive surgical management of ovarian ITs at all ages.

The role of staging and adjuvant chemotherapy in stage I malignant ovarian germ cell tumors (MOGTs): the MITO-9 study

Background

Surgery followed by platinum-based chemotherapy is the standard of care for MOGCTs, except for stage IA dysgerminoma and stage IA grade 1 immature teratoma where surveillance only is recommended. The role of adjuvant chemotherapy and surgical staging is debated.

Patients and methods

Data from 144 patients with stage I MOGTs were collected among MITO centers (Multicenter Italian Trials in Ovarian Cancer) and analyzed.

Results

Fifty-five (38.2%) patients were affected by dysgerminomas, 49 (34%) by immature teratomas, 26 (18.1%) by yolk sac tumors and 14 (9.7%) by mixed tumors. Seventy-three (50.7%) patients receive surgery plus chemotherapy, while 71 (49.3%) patients underwent surgery alone. The latter group included 32 dysgerminomas (14 IA-13 Ix, 3 IB, and 2 IC), 34 immature teratomas (20 1A-13 IA grade 1, 6 Ix, 1 IB, and 7 IC), 4 mixed tumors and 1 yolk sac tumor. Forty-four patients did not received chemotherapy, even if it would have been indicated by recommended approach. 94 (65.3%) patients received peritoneal surgical staging. Twenty-three (15.9%) developed a recurrence. Incomplete surgical staging was associated with recurrence (P < 0.05; OR 2.37) at Cox regression analysis. Seven patients died. Four patients were affected by yolk sac tumors, two by mixed tumors and one by immature teratoma. Five patients died for disease, one for acute leukemia and one for suicide. Prognostic parameter analyses showed that yolk sac component is a predictor for survival (P < 0.05). Five-years OS rates were 96.8% and 88.7% in the surgically staged and the incomplete staged group, respectively, while 93.8% and 94.1% in the standard treatment and in the surveillance group, respectively.

Conclusions

This study shows that surveillance seems not to affect survival; chemotherapy should be reserved for relapse resulting in high cure rate. Incomplete peritoneal surgical staging is associated with recurrence. Yolk sac histology worsens the prognosis.

Malignant ovarian germ cell tumors in pediatric patients: The AIEOP (Associazione Italiana Ematologia Oncologia Pediatrica) study

OBJECTIVE

Malignant ovarian germ cell tumors (MOGCT) carry an excellent prognosis, and the treatment aims to achieve results with the least possible treatment-related morbidity. The aim of this study was to assess the outcomes of pediatric patients with MOGCT.

METHODS

Patients were treated according to their stage: surgery and surveillance for stage I; a modified bleomycin-etoposide-cisplatin (BEP) regimen for stages II (three cycles), III, and IV (three cycles) with surgery on residual disease.

RESULTS

Seventy-seven patients were enrolled (median age 11.8 years), 26 with dysgerminoma (Dysg), 13 with immature teratoma and elevated serum alpha-fetoprotein levels (IT + AFP), and 38 with nondysgeminoma (Non-Dysg) staged as follows: 27 stage I, 13 stage II, 32 stage III, 5 stage IV. Among evaluable patients in stage I (5-year event-free survival [EFS] 72.1% [95% CI: 56.4-92.1%]; 5-year overall survival [OS] 100%), seven relapsed (three patients with Dysg and four patients with Non-Dysg) and were rescued with chemotherapy (plus surgery in three patients). Among the evaluable patients with stages II-IV, 48 (98%) achieved complete remission after chemotherapy ± surgery, one (IT + AFP, stage IV) had progressive disease. In the whole series (median follow-up 80 months), the 5-year OS and EFS were 98.5% (95% CI: 95.6-100%) and 84.5% (95% CI: 76.5-93.5%).

CONCLUSIONS

We confirm the excellent outcome for MOGCT. Robust data are lacking on surgical staging, surveillance for Non-Dysg with stage I, the management of IT + AFP, and the most appropriate BEP regimen. As pediatric oncologists, we support the role of surveillance after proper surgical staging providing cases are managed by experts at specialized pediatric centers.