Concept: Germ cell tumor
Tumor marker kinetics predict outcome in patients with relapsed disseminated non-seminomatous germ-cell tumors
- Annals of oncology : official journal of the European Society for Medical Oncology / ESMO
- Published almost 6 years ago
Background An early serum tumor marker ™ decline during chemotherapy was shown to independently predict survival in patients with poor-prognosis disseminated non-seminomatous germ-cell tumors (NSGCTs). The aim of this study was to assess whether a TM decline (TMD) also correlates with the outcome in the salvage setting. Patients and methods Data regarding 400 patients with progressive or relapsed disseminated NSGCTs after first-line chemotherapy prospectively accrued onto two phase III clinical trials were obtained. Serum alpha-fetoprotein (AFP) and/or human chorionic gonadotropin (hCG) were assessed at baseline and after 6 weeks of chemotherapy. A total of 297 patients, 185 and 112 in the training and validation sets, with initially abnormal TMs for whom a change from baseline could be established were used for this analysis. Results An unfavorable decline in either AFP or hCG was predictive of progression-free survival (PFS) [hazard ratio, HR = 2.15, (95% CI 1.48-3.11); P < 0.001; 2-year PFS rate: 50% versus 26%] as was the Lorch prognostic score (LPS). In the multivariate analysis, an unfavorable TMD, stratified based on the LPS, was an independent adverse prognostic factor for PFS and OS. Conclusion An unfavorable TMD during the first 6 weeks after chemotherapy is associated with a poorer outcome in patients with relapsed disseminated NSGCTs.
Testicular germ cell tumors (TGCTs) are among the most responsive solid cancers to conventional chemotherapy. To elucidate the underlying mechanisms, we developed a mouse TGCT model featuring germ cell-specific Kras activation and Pten inactivation. The resulting mice developed malignant, metastatic TGCTs composed of teratoma and embryonal carcinoma, the latter of which exhibited stem cell characteristics, including expression of the pluripotency factor OCT4. Consistent with epidemiological data linking human testicular cancer risk to in utero exposures, embryonic germ cells were susceptible to malignant transformation, whereas adult germ cells underwent apoptosis in response to the same oncogenic events. Treatment of tumor-bearing mice with genotoxic chemotherapy not only prolonged survival and reduced tumor size but also selectively eliminated the OCT4-positive cancer stem cells. We conclude that the chemosensitivity of TGCTs derives from the sensitivity of their cancer stem cells to DNA-damaging chemotherapy.
Type II testicular germ cell cancers (TGCT) are the most frequently diagnosed tumours in young men (20-40 years) and are classified as seminoma or non-seminoma. TGCTs are commonly treated by orchiectomy and chemo- or radiotherapy. However, a subset of metastatic non-seminomas (embryonal carcinomas) displays only incomplete remission or relapse and requires novel treatment options. Recent studies have shown effective application of the small-molecule inhibitor JQ1 in tumour therapy, which interferes with the function of ‘bromodomain and extraterminal (BET)’ proteins. JQ1-treated TGCT cell lines display up-regulation of genes indicative for DNA damage and cellular stress response and induce cell cycle arrest. Embryonal carcinoma (EC) cell lines, which presented as JQ1 sensitive, display down-regulation of pluripotency factors and induction of mesodermal differentiation. In contrast, seminoma-like TCam-2 cells tolerated higher JQ1 concentrations and were resistant to differentiation. ECs xenografted in vivo showed a reduction in tumour size, proliferation rate and angiogenesis in response to JQ1. Finally, the combination of JQ1 and the histone deacetylase inhibitor romidepsin allowed for lower doses and less frequent application, compared with monotherapy. Thus, we propose that JQ1 in combination with romidepsin may serve as a novel therapeutic option for (mixed) TGCTs.
A sizable fraction of testicular germ cell tumour (TGCT) risk is expected to be explained by heritable factors. Recent genome-wide association studies (GWAS) have successfully identified a number of common SNPs associated with TGCT. It is however, unclear how much common variation there is left to be accounted for by other, yet to be identified, common SNPs and what contribution common genetic variation makes to the heritable risk of TGCT. We approached this question using two complimentary analytical techniques. We undertook a population-based analysis of the Swedish family-cancer database, through which we estimated that the heritability of TGCT at 48.9% (CI:47.2%-52.3%). We also applied Genome-Wide Complex Trait Analysis to 922 cases and 4,842 controls to estimate the heritability of TGCT. The heritability explained by known common risk SNPs identified by GWAS was 9.1%, whereas the heritability explained by all common SNPs was 37.4% (CI:27.6%-47.2%). These complementary findings indicate that the known TGCT SNPs only explain a small proportion of the heritability and many additional common SNPs remain to be identified. The data also suggests that a fraction of the heritability of TGCT is likely to be explained by other classes of genetic variation, such as rare disease-causing alleles.
Salvage therapy with high-dose chemotherapy (HDCT) and bone marrow transplant (BMT) or peripheral blood stem cell transplant (PBSCT) has curative potential in patients with recurrent germ cell tumor. However, patients with primary mediastinal nonseminomatous germ cell tumors (PMNSGCTs) have had poor results with any form of salvage chemotherapy including HDCT. We switched from BMT to PBSCT in 1996. One hundred sixteen of 184 patients (63%) with recurrent or refractory germ cell tumors treated from 1996 to 2004 were alive and continuously disease-free. PMNSGCTs were excluded from that study because of poor results in the patient population with HDCT and BMTs. In 2006, we resumed treating patients with recurrent PMNSGCT with 2 consecutive courses of HDCT consisting of carboplatin 700 mg/m(2) × 3 plus etoposide 750 mg/m(2) × 3 and each followed by an infusion of autologous peripheral-blood hematopoietic stem cells with a second course 3 to 4 weeks later. Twelve patients were treated: 11 as initial salvage chemotherapy and 1 as fourth-line therapy. Eight of the 12 patients had major thoracic resections at the time of the relapse after initial chemotherapy. Three of the 12 patients achieved complete remission (CR; 10, 15, and 50 months' duration). One patient remains continuously with no evidence of disease (NED) at 50 months. An additional patient is currently NED at 52 months with HDCT and subsequent surgery. Median survival for the 12 patients was 11 months (range, 4-52 months). Results with tandem transplant for recurrent PMNSGCT remain poor compared to primary testis cancer, but durable CR and probable cure can be achieved in a small subset of patients with PMNSGCT. In our opinion, salvage surgical resection if anatomically feasible is the preferred option for patients with PMNSGT progressing after initial chemotherapy.
OBJECTIVE: We investigated the efficacy and toxicity of a docetaxel, ifosfamide and nedaplatin regimen as salvage therapy for patients with advanced testicular germ cell tumor. METHODS: Eleven patients with advanced germ cell tumor refractory or relapsed after cisplatin-based chemotherapy were treated using docetaxel, ifosfamide and nedaplatin. The docetaxel, ifosfamide and nedaplatin regimen comprised docetaxel (75 mg/m(2)) on Day 1, ifosfamide (2 g/m(2)) on Days 1-3 and nedaplatin (75 mg/m(2)) on Day 2 of a 3-week cycle. RESULTS: Ten (91%) of the 11 patients achieved favorable responses, including complete response in one case and partial response in nine cases. Nine (81%) of the 11 patients have continued to show no evidence of disease after docetaxel, ifosfamide and nedaplatin therapy followed by subsequent surgical resection, with a median follow-up period of 52 months. One patient died of the disease 3 months after completing docetaxel, ifosfamide and nedaplatin chemotherapy. One patient was lost to follow-up with a status of alive with disease. Ten (91%) of the 11 patients developed Grade 4 leukopenia, which was managed using granulocyte colony-stimulating factor. No patients developed sensory neuropathy or renal dysfunction. CONCLUSIONS: The docetaxel, ifosfamide and nedaplatin regimen was efficacious and well-tolerated as salvage chemotherapy for patients with advanced germ cell tumor.
A 22-year-old man with primary mediastinal choriocarcinoma and bilateral lung metastases underwent an FDG PET/CT scan after completing chemotherapy. Serum beta-human chorionic gonadotropin had normalized. PET/CT showed increased FDG uptake in the anterior mediastinal and lung lesions, suspicious for residual disease. After resection of the mediastinal and lung lesions, histopathology revealed necrosis and fibrohistiocytic reaction with no viable tumor. There was discordance between beta-human chorionic gonadotropin (negative) and FDG PET/CT (positive) findings, with PET/CT findings being false positive. Awareness of this potential pitfall of FDG PET/CT is important, and caution should be exercised when using FDG PET/CT to assess residual masses after chemotherapy.
Primary non-seminomatous germ cell tumours of anterior mediastinum are uncommon. Endodermal sinus tumour of the anterior mediastinum (yolk sac) is a rare but lethal neoplasm. We present a case of an 18-year-old man who presented with chest pain, cough and haemosputum with markedly raised serum α-fetoprotein (AFP) levels above 112 000 ng/mL. Chest roentgenogram and CT showed a giant anterior mediastinal mass. CT guided biopsy revealed a diagnosis of endodermal sinus tumour. After the completion of chemotherapy, extensive surgical resection was carried out along with the right lung metastastectomy. Five years postresection follow-up the patient is disease free with normal serum tumour markers. This is the longest survival ever reported of such tumours with highest AFP level (>112 000 ng/mL) and lung metastasis.
Therapeutic options for clinical Stage I nonseminomatous germ cell tumor include active surveillance, adjuvant chemotherapy and retroperitoneal lymph node dissection (RPLND). Lymphovascular invasion (LVI) determines risk of recurrence, as those without LVI have 15% risk of relapse on surveillance while those with LVI have a 50% risk. This stratifies patients into high risk(LVI+) and low risk(LVI-) groups which direct treatment recommendations. Surveillance is preferred for those with low risk disease, and is an option for those with high risk disease, as at least half are over-treated with other options. Adjuvant chemotherapy is an option for all patients as it can eradicate micrometastatic disease and reduce recurrence by at least 90%. RPLND benefits patients with low volume retroperitoneal disease with a cure rate of RPLND alone at approximately 70%. All three treatment modalities have similar survival rates approaching 100% but differing potential morbidities, which, along with patient preferences and compliance, should guide treatment decisions.
Protocols for pediatric germ cell tumors (GCT) allow for chemotherapy (CHT) initiation without histological diagnosis, based on typical clinical and radiological picture and increased alphafetoprotein (AFP) or beta-human chorionic gonadotropin serum levels. Such strategy may result in misdiagnoses in rare cases. We present two patients with abdominal tumors and high serum AFP levels, diagnosed as GCT. In both, no tumor shrinkage and increasing AFP was observed after first cycles of multidrug CHT for pediatric GCT. Histological examination of biopsied tumor tissues revealed metastatic cholangiocarcinoma in patient 1 and pancreatoblastoma in patient 2, which implicated immediate change of therapy. Presented cases support the necessity to consider the tumor biopsy when patients diagnosed with GCT based on typical clinical presentation and elevated AFP do not respond to CHT with AFP decrease and tumor size reduction.