Should CA-125 Response Criteria Be Preferred to Response Evaluation Criteria in Solid Tumors (RECIST) for Prognostication During Second-Line Chemotherapy of Ovarian Carcinoma?

Early Changes in CA125 After Treatment with Pegylated Liposomal Doxorubicin or Topotecan Do Not Always Reflect Best Response in Recurrent Ovarian Cancer Patients

PURPOSE

To examine early changes in CA125 relative to objective response in patients with recurrent ovarian cancer treated with pegylated liposomal doxorubicin (PLD) or topotecan and to compare the CA125 trends between the two chemotherapeutics.

PATIENTS AND METHODS

Patients with recurrent ovarian cancer, all of whom had measurable or evaluable disease, were randomized to receive 50 mg/m2 PLD every 28 days (n = 239) or 1.5 mg/m2 topotecan for 5 days every 21 days (n = 235) as part of a previously reported multicenter study. CA125 measurements were obtained prior to therapy and with each cycle of administration. Assessable patients underwent radiographic evaluation for response after two cycles of therapy. Objective responses were compared to trends in CA125 values at the end of cycles 1 and 2. CA125 changes were categorized as baseline (+/-10%), +/- 10%-25% variance, and > 25% variance.

RESULTS

Among patients treated with PLD, 50% of complete responders (CR) and 41% of partial responders (PR) had increases in CA125 from baseline to cycle 1. Increases in CA125 were also seen in topotecan-treated patients; however, fewer patients had increases (20% and 8%, respectively). Overall, 15% of responding patients (CR + PR) receiving PLD and 6% receiving topotecan had elevated CA125 after two cycles of therapy. For those patients achieving a partial response, 19% of PLD-treated patients and 8% of topotecan-treated patients had CA125 levels above baseline at cycle 2.

CONCLUSIONS

Considerable intrapatient variation in CA125 values is present among responding patients. Early increases in CA125 may not predict ultimate outcome, especially in PLD-treated patients.

Salvage bevacizumab (rhuMAB VEGF)-based therapy after multiple prior cytotoxic regimens in advanced refractory epithelial ovarian cancer

OBJECTIVES

Bevacizumab (BEV) is a humanized monoclonal antibody against vascular endothelial growth factor. We reviewed our experience with BEV in patients with recurrent advanced epithelial ovarian cancer who had failed multiple prior chemotherapeutic regimens.

METHODS

Thirty-two patients not participating in an ongoing clinical trial were treated with BEV (15 mg/kg every 3 weeks IV). Demographic and clinicopathologic data, clinical outcomes, and adverse events were extracted from patient charts. RECIST and CA-125 Rustin criteria were retrospectively applied to evaluate response and progression. Median progression-free survival (PFS) and overall survival (OS) were determined using Kaplan-Meier methods. Adverse events were retrospectively categorized using the common terminology criteria for adverse events version 3.

RESULTS

The median patient age was 57 years (range 35-80) with 84% being Caucasian and 50% having a GOG performance status of 2. FIGO stages included 80% stage III and 10% stage IV. The tumors were mostly grades 2 (29%) and 3 (64%) and serous histological subtype (69%). All patients had failed multiple prior cytotoxic chemotherapies (median of 5 (range 2-10)) prior to BEV. The median duration of follow-up was 4.8 months (range 0.4-16.3). Twenty-three patients were treated with BEV alone, 2 received BEV with another chemotherapy regimen (5-FU/lecovorin plus oxaliplatin, cyclophosphamide), and 8 initially received BEV alone, followed by BEV with capcitabine, cyclophosphamide, docetaxel, carboplatin, or weekly paclitaxel. A median of 6 cycles (range 1-20) with 196 total doses of BEV was administered. One patient was lost to follow-up after cycle 1. We observed a 16% response rate (all in those treated with BEV alone) with 62.5% of patients demonstrating stable disease. Median OS was 6.9 months, and the median PFS was 5.5 months. Three grade 3 and no grade 4 adverse events were observed. Grade 3 toxicities included hypertension, proteinuria, and enterocutaneous fistula. The fistula occurred after 5 cycles of BEV in a patient who had undergone 7 debulking surgeries prior to BEV.

CONCLUSIONS

BEV is generally well tolerated after multiple prior cytotoxic regimens and results in significant clinical benefit among women with recurrent ovarian cancer.

Phase II evaluation of a 3-day infusion of topotecan in patients with recurrent ovarian or primary peritoneal cancer

OBJECTIVE

To assess the efficacy and toxicity profile in patients treated with topotecan at 2.0 mg/m2/day x 3 days every 3 weeks.

MATERIALS AND METHODS

Eligibility criteria included patients with recurrent primary peritoneal or epithelial ovarian cancer with > or =6 months elapsed from time of prior platinum treatment. Patients were required to have a performance status of < or =2 and normal hepatic and renal function. Response to therapy and toxicity was assessed using standard criteria. Chi-square and Student's t tests were used as appropriate. Survival was assessed with Kaplan-Meier method.

RESULTS

All 40 patients enrolled were assessable for response. The mean age of the patients was 63.2 years (range 43-85). Median time to progression from initial treatment was 11.8 months. A total of 286 cycles of chemotherapy were administered with an average of 7.1 cycles per patient. Overall median time to progression (TTP) with 3-day topotecan treatment was 21 weeks (range 6-43 weeks). Of the 33 patients with measurable disease, 24% (11-42%, 95% CI) demonstrated a response. Seven patients had CA-125 evaluable disease with a response of 43% (10-89%, 95% CI). Median progression-free survival (PFS) was 16 weeks (range 12-21 weeks, 95% CI). Median overall survival was 106 weeks (range 76-117 weeks, 95% CI). Assessment of toxicity by patient showed 90% demonstrating grade 3/4 neutropenia with the vast majority being uncomplicated. No severe non-hematological toxicity was observed.

CONCLUSION

Administration of topotecan as a 3-day regimen is feasible with demonstrable activity and tolerable toxicity. Critical comparison to the 5-day regimen in a randomized fashion is warranted.

CA-125 response in patients with recurrent ovarian or primary peritoneal cancer treated with pegylated liposomal doxorubicin or topotecan

OBJECTIVE

Recent additions of novel chemotherapeutics, such as pegylated liposomal doxorubicin (PLD) and topotecan (TPT), have provided clinicians with multiple options for treating recurrent ovarian cancer. Evaluating treatment response in patients without radiographic or physically measurable disease is problematic, thereby CA-125 values may be the only available objective criteria. It has been advocated that several cycles of novel agents are required prior to an observed CA-125 response. In this study, we sought to gain insight into response patterns regarding CA-125 in responders vs. non-responders and to determine whether specific "cut-off" values could help predict ultimate clinical response.

METHODS

Patients with recurrent ovarian cancer who received either single agent PLD, TPT, or both were included. CA-125 levels were evaluated prior to initiation of chemotherapy and thereafter for each additional cycle. The Rustin criteria were utilized to evaluate CA-125 response.

RESULTS

Fifty-four of 120 patients were judged to be responders. When comparing responders to non-responders, as expected, the majority of responders demonstrated a decrease after each of the first 4 cycles. However, nearly 50% of responders who received PLD demonstrated an increase in CA-125 after cycle 1. There were no responders who demonstrated two successive rises in CA-125.

CONCLUSION

The majority of patients with recurrent ovarian cancer who will ultimately manifest a CA-125 response to novel agents, such as TPT or PLD, will demonstrate a decrease following each cycle. An initial increase in CA-125 should not mandate discontinuation of current therapy, but a successive rise over two or more cycles reliably predicts that a treatment response ultimately is unlikely.

RECIST revisited: a review of validation studies on tumour assessment

The response evaluation criteria in solid tumours (RECIST) was developed in the late 1990s to replace the WHO criteria for response evaluation. The new criteria included important changes such as unidimensional tumour measurement, selection of target lesions with a minimum size, details concerning imaging modalities and a new threshold for assignment of objective progression. RECIST was published in February 2000 and very quickly came into operation first in clinical trials performed under the auspices of EORTC, US NCI or NCI Canada Clinical Trials Group but was adopted quickly thereafter by the entire cancer clinical research community. As several key features of RECIST were based on analysis of retrospective clinical data, it was felt important to carefully monitor the implementation of the guidelines and stimulate prospective validation studies. This paper reviews the literature that has been published on RECIST from 2000 up to November 2005. In total 60 papers and ASCO, abstracts directly refer to research studies or reviews related to RECIST and its implementation. Amongst the 60 references identified for this review, 11 papers refer to validation studies (seven prospective and four retrospective), six papers refer to the comparison of unidimensional measurements versus bi or tri-dimensional measurements, 12 papers address issues raised with the implementation of RECIST in Mesothelioma and Gastro-Intestinal Stromal Tumours and four papers report on an adaptation of RECIST for specific tumour types. In general, RECIST has been well received by the scientific community and most validation studies fully support the implementation of the new criteria. As expected, however, some issues have been identified. In keeping with the mathematical differences in definition of progression, RECIST delays the identification of progression as compared to WHO criteria in some instances. RECIST criteria are not easily applicable in some types of trials such as those in paediatric tumours and in mesothelioma. Furthermore, anatomical changes in the tumour as described by RECIST may be detected later than functional changes in some circumstances, as for example in Gastro-Intestinal Stromal Tumours treated with Imatinib. However, there is no other universal method of tumour assessment as yet and functional imaging methods have not been validated and will not be widely available for some time. The findings of this review, together with experience acquired thus far and the results of some ongoing research projects, have paved the way for RECIST 2.0 to be hopefully announced later this year.

Prognostic value of FDG-PET in patients with ovarian carcinoma following surgical treatment

OBJECTIVE

[corrected] To determine the prognostic value of FDG-PET after surgical resection in patients with ovarian carcinoma, we compared the results of FDG-PET and serum CA-125 level and prognosis of patients.

METHODS

Eighteen patients underwent a total of 32 FDG-PET examinations following surgery for ovarian carcinoma from October 2001 to December 2002 at our hospital (median follow-up period, 31 months). Age of the patients at the time of the initial FDG-PET examination ranged from 31 to 73 years (mean 52 years) and the period from surgery to the initial FDG-PET examination ranged from 5 to 109 months (mean 30 months). Serum CA-125 levels were determined on the occasion of each FDG-PET examination. Recurrent tumors were treated with surgery in 5 cases, radiotherapy in 2 cases, and chemotherapy in 9 cases.

RESULTS

The initial FDG-PET examinations revealed that 13 cases had positive and 5 cases had negative findings, which included 2 false positive cases. The survival rate for all patients at 1 year and 2 years after the initial examination was 82% and 63%, respectively. Two-year survival rates in patients with positive and negative FDG-PET findings were 51% and 83%, respectively, and the difference was not statistically significant (p = 0.19). Furthermore, 4 patients with normal CA-125 levels and 14 patients with elevated CA-125 levels showed 2-year survival rates of 100% and 51%, respectively, and they were not significantly different (p = 0.11). For all 32 examinations, the 2-year survival rates for patients with normal CA-125 levels (100%) were significantly higher (p = 0.025) than that for patients with elevated CA-125 levels (47%), however there was no significant difference (p = 0.20) between FDG-PET positive cases (53%) and negative cases (83%). CONCLUSION The prognosis of patients with positive FDG-PET findings was less favorable than that of patients with negative findings. However, over the mean extended observation period of about 2.5 years, no significant difference in the prognosis of patients was observed between the two groups. The results of the present study indicate that elevated serum CA-125 levels may be more useful for evaluating the prognosis of ovarian cancer during the post-operative follow-up than FDG-PET findings.

A study to evaluate the use of CA125 in ovarian cancer follow-up: A change in practice led by patient preference

OBJECTIVES

To evaluate the use of CA125 in the follow-up of women with epithelial ovarian cancer in the Cambridge Gynaecologic Oncology Centre. To institute changes depending on patients' preferences.

METHODS

A patient questionnaire was developed on follow-up, CA125 estimation and patient education in epithelial ovarian cancer and CA125. Initially, 100 patients were evaluated, and a change in practice was instituted. This was re-evaluated using the same patient population.

RESULTS

22/22 patients in clinic, and 68/78 patients who received the questionnaire by post, completed and returned it (n = 90). 81% wanted CA125 results available at clinic follow-up visits, with 82% willing to have the blood test done at their GP surgery before attending outpatients. CA125 follow-up practice was changed accordingly. This change was re-evaluated. A second questionnaire was sent to 35 surviving patients from the first cohort. 31/35 (90%) responses were received. Five patients were either no longer on follow-up, being > or =5 years from completing their original treatment or were being monitored elsewhere, leaving an 87% response rate (26/30). 92.3% felt that having CA125 results available in clinic had enhanced the quality of their follow-up. Patient education and basic understanding of CA125 also improved, with 88.5% aware of its role.

CONCLUSIONS

The availability of CA125 results when patients attend for routine follow-up has improved their overall management in our clinics. It has reduced patient and physician anxiety and unsatisfactory out-of-clinic telephone communication. We recommend this change of practice to all Gynaecologic Oncology Centres engaged in active routine follow-up of their patients with epithelial ovarian cancer.

A phase II study of a paclitaxel and oxaliplatin combination in platinum-sensitive recurrent advanced ovarian cancer patients

PURPOSE

A multicentric, phase II study to evaluate the efficacy and safety of the combination paclitaxel and oxaliplatin in patients with platinum-sensitive recurrent ovarian cancer.

PATIENTS AND METHODS

Patients received 175 mg/m(2) paclitaxel (over 3 h) followed by 130 mg/m(2) oxaliplatin (over 2 h) every 21 days for up to nine cycles without hydration or primary granulocyte colony-stimulating factor prophylaxis. Patients had to have an Eastern Cooperative Oncology Group performance status of 0-2 and to have received no more than one prior cisplatin- and/or carboplatin-containing chemotherapy regimen with a platinum-progression-free interval > or =6 months.

RESULTS

Of the 105 patients enrolled and treated, 98 were eligible. An overall response rate of 81% (79 of 98 patients) (95% confidence interval 71% to 88%) was observed according to RECIST criteria (third party reviewed), and 88% (86 of 98) when this was complemented with CA-125 response. With a median follow up of 43.6 months (range 30.2-64.2) the median progression-free survival was 10.2 months (range 0.3-21.4) and the overall survival 32.4 months. Seven hundred and eight cycles were administered (median seven per patient; range one to nine). A total of 67% of patients experienced National Cancer Institute Common Toxicity Criteria grade 3-4 neutropenia, including 8% with concomitant febrile episode, without treatment-related deaths. Ninety-three per cent of patients experienced neuropathy of grade 1 or more, including 25% with cumulative reversible peripheral neuropathy of grade 3-4. Oxaliplatin doses were reduced in 30 patients due to neurotoxicity.

CONCLUSIONS

The oxaliplatin/paclitaxel combination can be administered in an outpatient setting every 3 weeks without specific measures. The high level of activity and its duration observed warrants further evaluation of this combination in pretreated platinum-sensitive advanced ovarian cancer patients.

Two for good measure: six versus eight cycles of carboplatin and paclitaxel as adjuvant treatment for epithelial ovarian cancer

INTRODUCTION

Although the standard of care for advanced epithelial ovarian cancer (EOC) is six cycles (6C) of platinum-taxane (PT), there have been no studies on the optimal duration of treatment in the era of adjuvant taxanes. At our center, some women receive eight cycles (8C) of PT, based on physician judgment. We were interested in evaluating the outcomes of women treated with 8C of PT for EOC as compared to a cohort who received 6C.

METHODS

We retrospectively identified women with Stage III or IV EOC between 1998 and 2003 who received 6C or 8C of PT. The endpoints were disease-free (DFS) and overall survival (OS). CA-125 response was defined as a decrease in CA-125 of 50% in four serial samples or of 75% over three samples.

RESULTS

One hundred and twenty-two women met criteria for inclusion; 84 received 6C, and 38 received 8C. Comparing the cohorts receiving 6C versus 8C, 71% versus 26% were optimally debulked (P < 0.01). 79 patients were evaluable by CA-125 (52 6C/27 8C), and all responded. 88% receiving 6C and 81% receiving 8C normalized their CA-125 at end of treatment (P = 0.20). The proportion with a normal CA-125 at Cycle 2 was 29% versus 12%, respectively (P = 0.15) and, at Cycle 4, was 88% versus 36%, respectively (P < 0.01). DFS was 13 months with 6C and 8 months with 8C (P = 0.01). OS was 31 versus 23.5 months (P = 0.02), respectively. When the survival analysis is restricted to suboptimal debulked patients only, the DFS is 12.5 versus 8 months (P = 0.02), and OS is 32 versus 26.5 months (P = 0.15), respectively.

CONCLUSIONS

Two further cycles of PT did not improve DFS or OS for patients with advanced EOC. Patients who do not achieve remission after 6C are unlikely to benefit from additional chemotherapy using the same agents and should be considered for clinical trials involving novel agents with different mechanisms of action.

A6, a urokinase plasminogen activator (uPA)-derived peptide in patients with advanced gynecologic cancer: a phase I trial

OBJECTIVES

The aim of this study was to define the toxicity, maximum feasible dose (MFD), and pharmacokinetics (PK) of A6, a peptide derived from human urokinase plasminogen activator (uPA), in patients with advanced gynecologic cancers, and to explore anti-tumor activity and the effects of A6 on biomarkers of the urokinase system.

METHODS

A6 was administered subcutaneously daily, and doses were escalated in cohorts of three to six subjects. Serial blood specimens were obtained for pharmacokinetics and levels of urokinase plasminogen activator (uPA), uPA receptor (uPAR), and plasminogen activator inhibitor-1 (PAI-1).

RESULTS

Sixteen patients were enrolled and eligible for evaluation. No serious drug-related adverse events or dose-limiting toxicity occurred. A6-related toxicities were limited to grades 1 and 2 adverse effects including local injection site reactions. Five patients had stable tumor measurements for at least 4 cycles, one of whom stayed on study for 12 months. One patient had a confirmed cancer antigen (CA)-125 response (decrease in CA-125 of >50%) with stable disease on CT scan after 14 cycles and continues on study. Time to peak plasma level of A6 was 1-2 h. C(max) is proportional to dose. The half-life of A6 was approximately 2 h. Baseline biomarker levels did not predict response and trends over time did not correlate with outcome.

CONCLUSIONS

A6 given daily continuously is well tolerated at all dose levels, without any dose-limiting toxicity. Based on the preliminary activity of A6, a phase II trial is underway in ovarian cancer.

Patupilone induced vascular disruption in orthotopic rodent tumor models detected by magnetic resonance imaging and interstitial fluid pressure

PURPOSE

Evaluation of vascular disruptive activity in orthotopic models as potential surrogate biomarkers of tumor response to the microtubule-stabilizing agent patupilone.

EXPERIMENTAL DESIGN

Mice bearing metastatic B16/BL6 melanoma and rats bearing mammary BN472 tumors received vehicle or efficacious patupilone doses (4 and 0.8-1.5 mg/kg i.v., respectively). Tumor vascularity assessment by dynamic contrast-enhanced or dynamic susceptibility contrast magnetic resonance imaging and interstitial fluid pressure (IFP) occurred at baseline, 2 days (mice and rats), and 6 days (rats) after treatment and were compared with histologic measurements and correlated with tumor response.

RESULTS

In B16/BL6 metastases, patupilone (4 mg/kg) induced a 21 +/- 5% decrease (P < 0.001) in tumor blood volume and a 32 +/- 15% decrease (P = 0.02) in IFP after 2 days and reduced tumor growth and vessel density (>42%) after 2 weeks (P < or = 0.014). Patupilone dose-dependently inhibited BN472 tumor growth (day 6) and reduced IFP on days 2 and 6 (-21% to -70%), and the percentage change in IFP correlated (P < 0.01) with the change in tumor volume. In both models, histology and vascular casts confirmed decreases in tumor blood volume. One patupilone (0.8 mg/kg) administration decreased (P < 0.01) tumor IFP (54 +/- 4%), tumor blood volume (50 +/- 6%), and vessel diameter (40 +/- 11%) by day 6 but not the apparent diffusion coefficient, whereas histology showed that apoptosis was increased 2.4-fold and necrosis was unchanged. Apoptosis correlated negatively (P < 0.001) with IFP, tumor blood volume, and tumor volume, whereas tumor blood volume and IFP were correlated positively (P = 0.0005).

CONCLUSIONS

Vascular disruptive effects of patupilone were detected in situ using dynamic contrast-enhanced or dynamic susceptibility contrast magnetic resonance imaging and IFP. Changes in IFP preceded and correlated with tumor response, suggesting that IFP may be a surrogate biomarker for patupilone efficacy.

Treatment goals in ovarian cancer

Ovarian cancer remains the number one gynecological killer in the Western world. Most ovarian cancer patients present with advanced-stage disease and are treated with cytoreductive surgery followed by combination chemotherapy. While the majority of patients respond to treatment, most will relapse such that the 5-year survival rates for advanced disease are approximately 20-25%. Overall survival and progression-free survival (PFS) are the primary endpoints in clinical trials in patients with advanced ovarian cancer. In patients with early-stage ovarian cancer, PFS may be the preferred trial endpoint, whereas in patients with recurrent ovarian cancer, the primary goal of therapy remains palliation and control of symptoms. Recent studies in recurrent disease have demonstrated that chemotherapy can improve the endpoints of PFS and overall survival, and so they are being used as the primary endpoints for comparing new regimens in phase III trials in relapsed patients. However, it would be easier to compare new treatment modalities if a uniformly accepted instrument was available that could evaluate quality of life and symptom control.