Prolonged disease-free survival by maintenance chemotherapy among patients with recurrent platinum-sensitive ovarian cancer

Update on the Treatment of Recurrent Ovarian Cancer

Ovarian cancer is the leading cause of death for all gynecologic malignancies in developed countries, largely owing to the late stage of diagnosis. Despite response to initial surgery and chemotherapy, more than 65% of patients will have recurrent or persistent diseases. Approximately 50% of patients with recurrent ovarian cancer are asymptomatic. Recurrences are often diagnosed using a combination of tests, including cancer antigen 125, computed tomography, magnetic resonance imaging and positron emission tomography scan. The most significant prognostic factor among women with recurrent ovarian cancer is the length of time from initial diagnosis to recurrence. Treatment of recurrent ovarian cancer involves chemotherapy, with or without surgery. In selected patients, secondary cytoreductive surgery might significantly improve survival. Radiotherapy may have a role in the treatment of a small group of patients with localized symptomatic masses. New treatment modalities for women with recurrent ovarian cancer are needed, as none of the available treatments are curative.

Maintenance chemotherapy in advanced ovarian cancer: the US experience

The somewhat controversial results of a Southwest Oncology Group/Gynecologic Oncology Group phase 3 randomized trial have revealed that a maintenance strategy consisting of 12 cycles of single-agent paclitaxel (175 mg/m2 over 3 h every 28 days), delivered to women with advanced ovarian cancer who have achieved a clinically defined complete response to primary platinum–paclitaxel chemotherapy, significantly improves progression-free survival compared to delivery of three cycles of the same treatment regimen. While it is not possible to provide a definitive statement regarding the impact of this management approach on overall survival, in an exploratory analysis, patients who initiated this study with a baseline CA-125 level ≤10 units/mL and were treated with the 12-cycle maintenance program experienced a statistically significant improvement in survival. An ongoing Gynecologic Oncology Group trial in the United States will hopefully provide a definitive answer to the question of the impact of this novel strategy on outcome in ovarian cancer.

Role of salvage cytoreductive surgery in the treatment of patients with recurrent ovarian cancer after platinum-based chemotherapy

OBJECTIVES

The role of cytoreductive surgery, which is well established in the primary treatment for epithelial ovarian cancer, is controversial in recurrent disease. The aim of this study was to assess the clinical benefit of salvage surgical cytoreduction in patients with recurrent ovarian cancer after platinum-based chemotherapy.

METHODS

We conducted a retrospective analysis of 46 patients with recurrent epithelial ovarian cancer treated at our department between 1988 and 2003. Twenty-three patients underwent salvage cytoreductive surgery (cytoreductive group), and the other 23 patients were treated without surgery (control group).

RESULTS

Patients in cytoreductive group had a median survival of 41.7 months after recurrence, which was significantly longer than control group (18.8 months; P < 0.01). The duration of stay at home and the period oral intake was preserved were significantly longer in the cytoreductive group. In the cytoreductive group, survival was influenced by the residual disease after surgery (residual tumor diameter, <2 cm vs >2 cm; median survival, 50 months vs 35.2 months; P < 0.05). However, the number of recurrent sites (solitary vs multiple) and the lengths of treatment-free intervals after primary treatment (<6 months vs >6 months) showed no significant influence on survival.

CONCLUSIONS

The application of cytoreductive surgery might improve the prognosis of patients with recurrent ovarian cancer if the tumor was resectable. Preserved prognoses of platinum-resistant disease with short treatment-free interval demonstrated in this study suggest that the concept of maximum cytoreduction might be introduced in the treatment of recurrent disease in the future.

Experience with single-agent paclitaxel consolidation following primary chemotherapy with carboplatin, paclitaxel, and gemcitabine in advanced ovarian cancer

OBJECTIVE

Twelve cycles of single-agent paclitaxel have been demonstrated to prolong progression-free survival in women with advanced ovarian cancer whom achieved a clinical complete response to a primary platinum/paclitaxel chemotherapy regimen. This trial was conducted to compare the toxicity and disease-free interval of 3 cycles vs. 12 cycles of paclitaxel consolidation in patients treated with an intensive three-drug front-line regimen of carboplatin, paclitaxel, and gemcitabine.

METHODS

Following cytoreductive surgery, 26 ovarian cancer patients received primary chemotherapy with carboplatin (AUC = 5, day 1), paclitaxel (175 mg/m(2) over 1 h, day 1), and gemcitabine (800 mg/m(2), day 1 day 8), with treatment repeated every 21 days x 6 cycles. The first 13 patients (group A) received three additional cycles of paclitaxel (175 mg/m(2) over 1 h every 21 days). The second set of 13 patients (group B) also received three cycles of paclitaxel (175 mg/m(2) over 1 h every 21 days) and then received nine additional cycles of paclitaxel (135 mg/m(2) over 1 h every 21 days) consolidation therapy. The change from 3 cycles to 12 cycles of consolidation therapy for group B was made following the published results of GOG 178.

RESULTS

In group A, all 13 patients completed three courses of consolidation therapy. One patient experienced grade 3 neutropenia and two patients exhibited both grade 4 neutropenia and thrombocytopenia. Grade > or = 2 neuropathy developed in 3 patients (23%). In group B, 9 of the 13 patients whom were intended to receive 12 total cycles of paclitaxel consolidation were able to complete the program. There was no grade 3-4 neutropenia or anemia in this population, although 1 patient developed grade 3 thrombocytopenia. Grade > or = 2 neuropathy developed in 7 patients (54%). Although not a randomized experience, median progression-free interval was 76 weeks for group B, and 47 weeks for group A.

CONCLUSION

Single-agent paclitaxel consolidation therapy can be administered for 12 cycles following first-line carboplatin, paclitaxel, and gemcitabine induction therapy, but there is considerable risk for development of a moderately severe peripheral neuropathy.

Maintenance treatment with interferon for advanced ovarian cancer: results of the Northern and Yorkshire gynaecology group randomised phase III study

A randomised phase III trial was conducted to assess the role of interferon-alpha (INFalpha) 2a as maintenance therapy following surgery and/or chemotherapy in patients with epithelial ovarian carcinoma. Patients were randomised following initial surgery/chemotherapy to interferon-alpha 2a as 4.5 mega-units subcutaneously 3 days per week or to no further treatment. A total of 300 patients were randomised within the study between February 1990 and July 1997. No benefit for interferon maintenance was seen in terms of either overall or clinical event-free survival. We conclude that INF-alpha is not effective as a maintenance therapy in the management of women with ovarian cancer. The need for novel therapeutics or strategies to prevent the almost inevitable relapse of patients despite increasingly effective surgery and chemotherapy remains.

Duration of response to second-line, platinum-based chemotherapy for ovarian cancer: implications for patient management and clinical trial design

PURPOSE

Limited information is available regarding the influence of the duration of a prior response on the length of a subsequent response to platinum chemotherapy in recurrent ovarian cancer.

PATIENTS AND METHODS

We retrospectively reviewed the medical records of women with ovarian cancer treated at the Cleveland Clinic from 1993 through April 2003 who received two or more platinum-based regimens for recurrence of the malignancy. Patients were considered to have responded to second-line therapy if they satisfied specific criteria, including favorable effects on both measurable or assessable disease.

RESULTS

A total of 211 platinum-based regimens were administered to 176 women with recurrent ovarian cancer during this time period, with a response being observed in 125 treatment episodes (59%). Only four (3%) of 121 currently assessable secondary responses were of longer duration than the prior response in a specific individual. In three of these four cases, the platinum-based regimen used in the second-line approach included a drug that had not been used in that patient's primary chemotherapy program.

CONCLUSION

The length of a prior response to platinum-based therapy in ovarian cancer is highly predictive of the upper limit of the duration of response to a subsequent platinum program, assuming the same or similar drugs are used. Knowledge of this clinical parameter may assist in developing optimal management for an individual patient and may potentially be exploited in clinical trial designs examining novel maintenance strategies with both cytotoxic and cytostatic agents in women who achieve a secondary response to a platinum-based regimen.

Consolidation/maintenance chemotherapy for ovarian cancer

A recently reported randomized trial has demonstrated that administration of single-agent paclitaxel to women with advanced ovarian cancer who attain a clinically defined complete response to platinum/paclitaxel-based chemotherapy can substantially improve progression-free survival. Whether this strategy will improve overall survival in this clinical setting remains uncertain.

Consolidation therapy revisited: intravenous chemotherapy

The administration of 'consolidation' therapy is designed to maximize the benefits achieved from primary chemotherapy, to both improve progression-free and overall survival. Paclitaxel is an excellent agent to consider for a consolidation strategy in ovarian cancer, based on its activity in the disease, its cycle-specificity, and the lack of serious cumulative toxicity (except for neuropathy). A recently reported randomized trial conducted by the South-west Oncology Group and the Gynecologic Oncology Group revealed that 12-monthly cycles of single-agent paclitaxel (175 mg/m2 over 3 h) improves progression-free survival (PFS), compared to 3-monthly cycles of the agent (median PFS: 28 months versus 21 months, P = 0.0023, and hazard ratio 2.31). Further exploration of consolidation/maintenance therapy in the management of ovarian cancer is indicated, focusing on agents that are easy to administer (eg, oral) and that result in limited cumulative toxicity.

A case of chronic paclitaxel administration in ovarian cancer

BACKGROUND

Treatment with chemotherapeutic agents, after initial ovarian tumor debulking, and during recurrence, results in extended chemotherapy. When ovarian cancer recurs, chemotherapy is continued when patients respond to therapy. However, the disease may become stable. Stable disease is clinically relevant and no longer an indication of treatment failure.

CASE

A woman with advanced ovarian cancer was treated with cytoxan and cisplatin chemotherapy after having surgical cytoreduction. She progressed and was placed on monthly intravenous paclitaxel. After an initial partial response to therapy, she then went into a prolonged stable course of her disease. She subsequently received 67 cycles of monthly paclitaxel therapy.

CONCLUSION

Chronic administration of paclitaxel resulted in prolonged stabilization of disease and was well tolerated.

Treatment preferences in recurrent ovarian cancer

OBJECTIVES

In the case of recurrent ovarian cancer, salvage therapy represents the potential to trade off between quality and quantity of life. Patient and physician face a choice between chemotherapy directed at slowing disease progression and supportive or palliative care that focuses on symptom management. To date, no studies have investigated the effects of best supportive care on ovarian cancer patients' quality of life and length of life as compared to salvage therapy. In other cancers, both quantity and quality of life considerations have been shown to affect treatment preferences.

METHODS

Using a decision board, we assessed preferences for salvage therapy or palliative care in the case of recurrent ovarian cancer among 81 ovarian cancer patients receiving first-line chemotherapy and 75 Noncancer Controls.

RESULTS

Compared to Noncancer Controls, ovarian cancer patients overwhelmingly preferred salvage therapy; quantity of life was of primary importance. In both groups, preference was not related to age, marital status, number of children, or employment status. On average, patients indicated they would switch from salvage therapy to palliative care when the median survival associated with salvage therapy was reduced to 5 months. Noncancer Controls would switch significantly sooner, when the median increment in survival period was reduced to 8 months. Switchpoint was not associated with life satisfaction, quality of life, or psychological or spiritual well-being in either group.

CONCLUSIONS

The majority of women, independent of a cancer diagnosis, indicated a desire for continuing aggressive treatment, despite poor outcomes. Quality of life was of secondary importance, especially among ovarian cancer patients.

Current treatment for ovarian cancer

Ovarian cancer is the most lethal gynaecologic malignancy. Epithelial ovarian cancer (EOC) constitutes approximately 90% of cases of ovarian cancer and 70% of the patients with EOC present in advanced stage. Treatment of EOC usually consists of cytoreductive surgery which includes total abdominal hysterectomy (TAH), bilateral salpingo-oophorectomy (BSO), omentectomy and lymphadenectomy followed by adjuvant chemotherapy. Current adjuvant chemotherapy includes paclitaxel and either cisplatin or carboplatin given every 3 weeks for six cycles. The combination paclitaxel and platinum chemotherapy achieves clinical response in approximately 80% of patients. However, most patients will have tumour recurrence within 3 years following treatment. Patients with platinum-sensitive tumours can be re-treated with platinum and/or paclitaxel. Those with platinum-resistant tumours have poor prognosis and treatment is palliative. Options of treatment in these patients include topotecan, doxil, gemcitabine, etoposide, or enrolment in clinical trials. Future research needs to focus on the role of cytoreductive surgery, second-look surgery, consolidation chemotherapy, development of new chemotherapeutic agents, chemoresistance modulators, as well as new approaches to the treatment of women with ovarian cancer.