High-dose melphalan and autologous stem cell transplantation as consolidation treatment in patients with chemosensitive ovarian cancer: results of a single-institution randomized trial

A Phase I Trial of High-Dose Chemotherapy Combining Topotecan plus Cyclophosphamide with Hematopoietic Stem Cell Transplantation for Ovarian Cancer: The ITOV 01bis Study

BACKGROUND

Dose-intensive chemotherapy with hematopoietic stem cell transplantation has been evaluated as a salvage treatment for recurrent ovarian cancer, but its benefit has not yet been demonstrated. In a previous phase I trial, we reported the feasibility of administering topotecan as a salvage regimen.

METHODS

Twenty-one patients were treated with escalating doses of topotecan associated with a fixed dose of cyclophosphamide.

RESULTS

The maximum tolerated dose was established at 9.0 mg/m2 on a 5-day regimen, analogously to what was reported for topotecan monotherapy. One toxic death from septic shock and multiorgan failure occurred. Although hematopoietic toxicities were overcome by peripheral blood stem cell transplantation, superior nonhematological toxicities were observed as compared to the initial trial.

CONCLUSION

Response rates were generally short and survival rates were poor. Results of the ITOV 01bis study demonstrate that, in the setting of recurrent ovarian cancer, intensive chemotherapy based on topotecan-cyclophosphamide association is not currently clinically indicated.

Intensive chemotherapy as salvage treatment for solid tumors: focus on germ cell cancer

Germ cell tumors present contrasting biological and molecular features compared to many solid tumors, which may partially explain their unusual sensitivity to chemotherapy. Reduced DNA repair capacity and enhanced induction of apoptosis appear to be key factors in the sensitivity of germ cell tumors to cisplatin. Despite substantial cure rates, some patients relapse and subsequently die of their disease. Intensive doses of chemotherapy are used to counter mechanisms of drug resistance. So far, high-dose chemotherapy with hematopoietic stem cell support for solid tumors is used only in the setting of testicular germ cell tumors. In that indication, high-dose chemotherapy is given as the first or late salvage treatment for patients with either relapsed or progressive tumors after initial conventional salvage chemotherapy. High-dose chemotherapy is usually given as two or three sequential cycles using carboplatin and etoposide with or without ifosfamide. The administration of intensive therapy carries significant side effects and can only be efficiently and safely conducted in specialized referral centers to assure optimum patient care outcomes. In breast and ovarian cancer, most studies have demonstrated improvement in progression-free survival (PFS), but overall survival remained unchanged. Therefore, most of these approaches have been dropped. In germ cell tumors, clinical trials are currently investigating novel therapeutic combinations and active treatments. In particular, the integration of targeted therapies constitutes an important area of research for patients with a poor prognosis.

Estimation of expectedness: predictive accuracy of standard therapy outcomes in randomized phase 3 studies in epithelial ovarian cancer

BACKGROUND

The anticipated clinical outcome of the standard/control arm is an important parameter in the design of randomized phase 3 (RP3) trials to properly calculate sample size, power, and study duration. Changing patterns of care or variation in the study population enrolled may lead to a deviation from the initially anticipated outcome. The authors hypothesized that recent changes in patterns of care in epithelial ovarian cancer (EOC) have led to challenges in correctly estimating the outcome of control groups.

METHODS

A systematic review of the literature was conducted for RP3 trials of EOC published between January 2000 and December 2010. The expected outcome of the control arm as well as the actual outcome achieved by this cohort was collected and a ratio (actual‐over‐expected ratio) was calculated. The estimation of outcome was deemed accurate if the outcome of the control arm was between 0.75 to 1.25 times the anticipated outcome.

RESULTS

A total of 35 trials were eligible for analysis. Fifteen trials had survival as the primary endpoint whereas 20 had a progression‐based primary endpoint. In total, 12 of 15 trials with a survival‐based endpoint significantly underestimated the outcome of the control arm, whereas only 4 of 20 trials with a progression‐based endpoint did. Studies with a survival endpoint underestimated outcome more frequently than those with a progression endpoint (P<.001).

CONCLUSIONS

Survival of the control arm has frequently been underestimated in recent EOC RP3 trials. This underestimation means that the initial statistical assumptions of these trials may have been inaccurate. Underestimating the outcome of the control arm may result in trials being underpowered to demonstrate the absolute benefit they were designed to show. Cancer 2015;121:413–422. © 2014 American Cancer Society.

The anticipated clinical outcome of the standard/control arm is an important parameter in the design of randomized phase 3 trials for the accurate calculation of sample size, power, and study duration but is often underestimated in ovarian cancer trials. Changing patterns of care and variations in enrolled study populations may result in a deviation from the anticipated outcome and subsequent inaccurate statistical assumptions.

Are there candidates for high-dose chemotherapy in ovarian carcinoma?

Background

Prognosis of advanced ovarian carcinomas (AOC) remains poor with a 5-year survival of 30%. Benefit from high-dose chemotherapy (HDC) in this disease has not been demonstrated to date.

Methods

To evaluate the value of HDC as consolidation treatment after surgery and platinum/taxane-based therapy, we designed a monocentric retrospective comparative study. We used a subset approach to identify parameters associated with HDC efficacy.

Results

One hundred and three AOC patients treated with conventional chemotherapy alone (CCA) were compared to 60 patients receiving HDC plus hematopoietic stem cell support. After a median follow-up of 47.5 months there was no overall survival (OS) advantage for the HDC group in the whole population (p=0.29). Nevertheless, HDC was associated to a better outcome in young patients (≤50 years), both in term of progression-free survival (p=0.02, log-rank test) and OS (p=0.05, log-rank test). Median OS was 54.6 and 36 months in the HDC and CCA groups, respectively.

Conclusions

Although randomized trials failed to demonstrate any benefit for HDC in AOC patients, this study suggests that young patients may derive a substantial advantage from receiving it after the standard treatment. Further prospective studies are warranted to confirm this gain and to search for the biological processes associated with this improvement.

Continued chemotherapy after complete response to primary therapy among women with advanced ovarian cancer: a meta-analysis

BACKGROUND

Ovarian cancer (OC) is associated with a >75% risk of recurrence after completion of primary therapy. Several clinical trials have explored the role of continued therapy after complete response to primary adjuvant therapy to reduce the risk of recurrence; however, these trials have largely been underpowered, leading to inconclusive results.

METHODS

A systematic search strategy was initiated to identify all clinical trials involving consolidation or maintenance therapy regimens for OC in first complete remission. A meta-analysis was conducted to evaluate toxicity and progression-free (PFS) and overall survival (OS).

RESULTS

There were 37 publications meeting all eligibility criteria, representing 20 consolidation and 9 maintenance therapy trials. Consolidation and maintenance therapies were associated with improved PFS (hazard ratio [HR], 0.79 [P = .003] and HR, 0.82 [P = .02], respectively) and OS (HR, 0.68 [P = .0008] and HR, 0.68 [P = .007], respectively). This relationship remained statistically significant when the analysis was limited to randomized trials and across other sensitivity analyses.

CONCLUSIONS

Although individual studies have not yet convincingly shown a survival advantage with maintenance chemotherapy in OC, this meta-analysis demonstrates that continued chemotherapy after completion of primary therapy for OC improves PFS and OS. Benefits are greatest in patients with advanced stage OC who reach complete clinical or pathologic response after primary therapy.

Stem cells in clinical practice: applications and warnings

Stem cells are a relevant source of information about cellular differentiation, molecular processes and tissue homeostasis, but also one of the most putative biological tools to treat degenerative diseases. This review focuses on human stem cells clinical and experimental applications. Our aim is to take a correct view of the available stem cell subtypes and their rational use in the medical area, with a specific focus on their therapeutic benefits and side effects. We have reviewed the main clinical trials dividing them basing on their clinical applications, and taking into account the ethical issue associated with the stem cell therapy.