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Published on: July 28, 2020
Evaluation of residual tissues after adjuvant therapy in germ cell tumors
Hideo Nakamura1, Hideo Takeshima, Keishi Makino
1Department of Neurosurgery, Graduate School of Medical Science, Kumamoto University, Kumamoto, Japan. hnakamur@fc.kuh.kumamoto-u.ac.jp
Objective:
Germ cell tumors are the tumors sensitive for adjuvant therapy such as radiotherapy and chemotherapy. We evaluated the pathological findings of these heterogeneous tumors to determine the persistence of residual viable tumor cells after adjuvant therapy.
Patients And Methods:
Between 1988 and 2005, we treated 31 patients with germinoma or germinoma with syncytiotrophoblastic giant cells (STGC) and 15 patients with non-germinomatous malignant germ cell tumors (NGMGCTs). All 46 patients received a combination of chemo- and radiotherapy. A second-look operation was performed in 3 of 31 patients with germinomas or germinomas with STGC and 12 of 15 patients with NGMGCTs. The follow-up period was 2-139 months (median 95) in patients with germinomas or germinomas with STGC (group 1) and 10-202 months (median 65) in NGMGCT patients (group 2).
Results:
Post-treatment, 3 group 1 and 12 group 2 patients manifested residual tumors. The pathological diagnosis in group 1 patients was mature teratoma, pineal cyst, and fibrous tissue with calcification; in group 2 it was yolk sac tumor (n = 1), immature teratoma (n = 3), mature teratoma (n = 4), and necrosis or fibrous tissue (n = 4). While no group 1 patients manifested tumor cells, MIB-1-positive viable tumor cells were present in resected tissues from one-third of the group 2 patients (3 immature teratomas and 1 yolk sac tumor).
Conclusion:
The absence of viable tumor cells in residual tissue indicates that the combination of cisplatin-based chemo- and radiotherapy was effective in our germinoma patients. On the other hand, in patients with NGMGCTs, these cells persisted despite this combination therapy.
Insights
Adjuvant chemo- and radiotherapy effectively eliminated viable tumor cells in germinoma patients. However, non-germinomatous malignant germ cell tumors showed persistent viable cells post-treatment, indicating varying treatment efficacy.
Area of Science:
- Oncology
- Pathology
Background:
- Germ cell tumors are sensitive to adjuvant therapies like chemotherapy and radiotherapy.
- Evaluating residual viable tumor cells post-treatment is crucial for assessing therapeutic effectiveness.
Purpose of the Study:
- To assess the pathological findings of residual germ cell tumors after combined chemo- and radiotherapy.
- To determine the persistence of viable tumor cells in germinoma and non-germinomatous malignant germ cell tumors (NGMGCTs) post-treatment.
Main Methods:
- Retrospective analysis of 46 patients treated between 1988-2005 with combined chemo- and radiotherapy.
- Patients included germinoma (n=31) and NGMGCTs (n=15).
- Second-look operations were performed on selected patients; pathological examination of residual tissue was conducted.
Main Results:
- No viable tumor cells were found in residual tissues of germinoma patients.
- Viable tumor cells (MIB-1 positive) persisted in one-third of NGMCT patients, including yolk sac tumors and immature teratomas.
- Residual pathologies in germinoma patients included mature teratoma, pineal cyst, and fibrous tissue with calcification.
Conclusions:
- Cisplatin-based chemo- and radiotherapy combination therapy is highly effective against germinomas.
- NGMGCTs demonstrate resistance to this combination therapy, with persistent viable tumor cells observed.
