Hexamethylmelamine as a single second-line agent in ovarian cancer: follow-up report and review of the literature

Neurological complications of chemotherapy to the central nervous system

One of the most common complications of chemotherapeutic drugs is toxicity to the central nervous system (CNS). This toxicity can manifest in many ways, including encephalopathy syndromes and confusional states, seizure activity, headache, cerebrovascular complications and stroke, visual loss, cerebellar dysfunction, and spinal cord damage with myelopathy. For many drugs, the toxicity is related to route of administration and cumulative dose, and can vary from brief, transient episodes to more severe, chronic sequelae. However, the neurotoxicity can be idiosyncratic and unpredictable in some cases. Among the antimetabolite drugs, methotrexate, 5-fluorouracil, and cytosine arabinoside are most likely to cause CNS toxicity. Of the alkylating agent chemotherapeutic drugs, the nitrosoureas (e.g., BCNU) and cisplatin most frequently cause toxicity to the CNS, especially when given via the intra-arterial route. Ifosfamide is also likely to cause neurotoxicity at high intravenous doses. Other alkylating agents, such as busulfan, cyclophosphamide, procarbazine, and temozolomide, are better tolerated by the CNS at moderate doses. The retinoid drugs are known to cause severe headaches at high doses. l-Asparaginase can induce an encephalopathy syndrome, as well as cerebrovascular complications such as stroke.

Hexamethylmelamine as consolidation treatment for patients with advanced epithelial ovarian cancer in complete response after first-line chemotherapy

The aim of this study was to assess the efficacy of consolidation therapy with hexamethylmelamine (HMM) in patients with advanced epithelial ovarian cancer (EOC). Patients treated at our hospital between January 1997 and November 2006 and in documented clinical complete response from advanced ovarian cancer following front-line platinum-based therapy were retrospectively analyzed. The patients treated with HMM were compared to the patients of matched counterpart without consolidation therapy. Of 102 patients enrolled, 49 were treated with HMM and 53 received no consolidation treatment. For patients with HMM and observed patients, the mean age were 54.6 and 55.6 yr; the distribution of stage was similar (P=0.977); the optimal surgery was performed in 36 (73.5%) and 44 (83%) (P=0.336); the recurrence rate were 27 (55.1%) and 33 (62.3%) (P=0.463); and the median progression-free survival were 38 months and 21 months for patients with HMM and observed patients (P=0.235). No treatment-related adverse events were reported during the follow-up period. Although this study failed to show the significant survival benefit of consolidation therapy with HMM in patients with advanced EOC, we consider that our study can contribute data to investigate the effectiveness of consolidation therapy in epithelial ovarian cancer.

Management of recurrent ovarian carcinoma: current status and future directions

The majority of patients who present with epithelial ovarian cancer respond well to the initial treatment, but will ultimately experience a recurrence of their disease. Chemotherapy can palliate symptoms of disease recurrence, and there is some evidence that it also can improve survival. Recurrent ovarian carcinoma is divided into two subsets of patients: those with platinum-sensitive disease and those with platinum-resistant disease. Management for these two groups has diverged in the last few years, as evidence accrues that the response to treatment and duration of treatment-free interval after completion of front-line therapy impacts the prognosis and the treatment choice for these patients. Recent randomized trials have demonstrated a benefit for platinum combination re-treatment in patients with platinum-sensitive disease. Additionally, there are multiple single-agent trials evaluating novel agents for patients with platinum-resistant as well as platinum-sensitive disease. This review will discuss the role of chemotherapy in recurrent disease, describe the various agents used in this setting, and touch on the role of biologic agents in recurrent epithelial ovarian carcinoma.

Recurrent low-grade serous ovarian carcinoma is relatively chemoresistant

PURPOSE

Previous studies have suggested that low-grade serous ovarian carcinoma is more chemoresistant to first-line or neoadjuvant chemotherapy than high-grade serous carcinoma. The purpose of this study was to further characterize this chemoresistance in recurrent low-grade serous ovarian carcinoma.

METHODS

From a 1990-2007 search of the departmental databases at our institution, we identified recurrent low-grade serous ovarian carcinoma patients; abstracted chemotherapy response information from the medical records of those whose disease was: 1) histologically-confirmed, 2) measurable or evaluable, and 3) treated with chemotherapy; and retrospectively reviewed these data. Response was determined based on modified RECIST. Time to progression and overall survival were also calculated.

RESULTS

We identified 58 evaluable patients with recurrent low-grade serous ovarian carcinoma who received 108 separate chemotherapy regimens ("patient-regimens"), which produced 4 responses-(1 complete and 3 partial; overall response rate, 3.7%). The overall response rate for the platinum-sensitive cohort was 4.9%, and for the platinum-resistant cohort, 2.1%. Stable disease was observed in 65 (60.2%) of 108 patient-regimens. Median overall survival was 87.1 months. The median time to progression was 29.0 weeks (34.7, platinum-sensitive cohort; 26.4, platinum-resistant cohort) (P=0.32).

CONCLUSIONS

Compared with high-grade ovarian cancers, recurrent low-grade serous ovarian carcinoma appears relatively chemoresistant. Whether the latter's high rate of stable disease owes more to the tumor's biology or the influence of chemotherapy remains unclear. Based on these findings, phase II trials of novel targeted agents in recurrent low-grade serous ovarian carcinoma are warranted.

Pharmaceutical management of ovarian cancer : current status

Over recent decades, truly impressive progress has been made in the outcome associated with the pharmacological antineoplastic management of women with advanced ovarian cancer. Following initial surgery, the large majority of patients with this malignancy will receive a chemotherapy regimen that includes a platinum drug (carboplatin or cisplatin) and a taxane (paclitaxel or docetaxel). Currently, objective responses are observed in approximately 60-80% of patients treated in the front-line setting, with documented improvements in overall survival compared with prior non-platinum and taxane programmes. Unfortunately, despite the high response rate to initial chemotherapy, the majority of women with advanced disease will experience recurrence of the malignant process and be candidates for a variety of possible second-line therapeutic options. It is well recognized that ovarian cancer patients who are documented to experience an initial response to platinum-based chemotherapy but where the disease recurs approximately 6 or more months following the completion of primary therapy, may have another clinically meaningful response (both objective and subjective) to a second platinum-based strategy. However, an optimal management approach in this setting remains to be defined. Furthermore, the malignant cell populations in all ovarian cancer patients who experience an initial relapse of the disease process will eventually be resistant to the platinum agents. In this setting, multiple drugs have been shown to be biologically active. Again, an optimal strategy to be employed in the platinum-resistant setting has yet to be demonstrated through the conduct of evidence-based trials. Reasonable goals of therapy in women with recurrent or resistant ovarian cancer are to improve overall survival, reduce the severity (and delay the occurrence) of symptoms and optimize overall quality of life.

Recurrent epithelial ovarian cancer: pharmacotherapy and novel therapeutics

Epithelial ovarian cancer will strike between 1 - 2% of women in developed countries and, unfortunately, it largely remains a lethal disease due to late-stage at diagnosis and the eventual development of chemotherapy resistance. Ovarian cancer is initially treated with surgical resection and chemotherapy (primarily platinum/taxane combinations) and remission can be attained for the majority of patients. Despite this, most women will recur and require multiple further therapies. The purpose of this paper is to review the existing treatment options, including surgery, traditional chemotherapy as well as upcoming novel and targeted therapies that may one day improve outcomes in this disease.

Optimizing gemcitabine regimens in ovarian cancer

Ovarian cancer represents the leading cause of death from gynecologic neoplasms. The chance of response to secondary treatment is currently disappointing; few agents have shown notable activity in recurrent/progressive patients. Among these agents, gemcitabine represents one of the most interesting newer antineoplastic agents, showing significant activity, synergism with cisplatin, and a mild toxicity profile in both platinum-sensitive and platinum-resistant (and also taxane-pretreated) recurrent/progressive patients. Moreover, first-line combination chemotherapy including gemcitabine has shown promising response rates in phase I and II studies. The ongoing phase III, five-arm, randomized Gynecologic Oncology Group Protocol 182/International Collaborative Ovarian Neoplasm 5 study should clarify the clinical impact of the addition of a third drug to the standard paclitaxel plus carboplatin treatment regimen.

Long-term follow-up of a phase II trial of oral altretamine for consolidation of clinical complete remission in women with stage III epithelial ovarian cancer in the Southwest Oncology Group

OBJECTIVE

This report provides follow-up progression-free survival (PFS) and median survival data for women who achieved clinical complete remission (cCR) from stage III ovarian cancer after first-line therapy and were treated with altretamine consolidation therapy.

METHODS

Patients who enrolled in the SWOG 9326 study from September 1993 to July 1997 were required to have documented cCR from stage III ovarian cancer following front-line platinum-based therapy. Treatment consisted of 6 months of oral altretamine at 260 mg/m(2)/day for 14 consecutive days of a 28-day cycle.

RESULTS

Ninety-seven of 112 enrolled patients were evaluable for efficacy. This report presents median 6.2-year follow-up, dating from study registration. Median PFS was 28 (95% CI: 19-43) months. Median PFS for patients with optimal disease was 45 (95% CI: 27-48) months and for patients with suboptimal disease was 17 (95% CI: 12-26) months. Twenty-six of 61 (43%) patients with optimally debulked lesions and 5 of 36 (14%) patients with suboptimally debulked lesions remained disease free. Median survival of patients with optimally debulked disease has not been reached; median survival of patients with suboptimally debulked disease was 39 (95% CI: 19-51) months. No treatment-related adverse events were reported during the follow-up period.

CONCLUSIONS

Consolidation therapy with oral altretamine was generally well tolerated and associated with prolonged progression-free and overall survival in the Phase II setting.

Chemotherapy for newly diagnosed and relapsed advanced ovarian cancer

OBJECTIVES

To review chemotherapy options for patients with newly diagnosed or relapsed advanced ovarian cancer.

DATA SOURCES

Published literature.

CONCLUSION

Primary chemotherapy for newly diagnosed, advanced ovarian cancer consisting of a platinum compound and a taxane is commonly associated with myelosuppression, nausea/vomiting, alopecia, and sensory/motor neuropathy. For recurrent disease, numerous chemotherapy agents are effective, including rechallenging the patient with a platinum and/or a taxane or using newer agents such as pegylated liposomal doxorubicin, topotecan, and gemcitabine. In platinum-resistant disease, selection is based mainly on the toxicity profile, because palliation and quality of life are important.

IMPLICATIONS FOR NURSING PRACTICE

Oncology nurses play a valuable role in ovarian cancer care by proactively meeting patient information needs.

Salvage therapy for recurrent epithelial ovarian cancer

There are no comparative prospective trials to support dogmatic statements concerning the sequence and duration of therapy in the salvage setting. Although the literature offers many examples of chemotherapy studies conducted in the salvage setting, these studies typically involve relatively small numbers of younger patients whose disease shows good performance. The extrapolation of these observations to the practice setting, compounded by the clinical and molecular heterogeneity of epithelial ovarian cancer, further exacerbates the difficulties encountered in individual treatment recommendations.

Part II: chemotherapy for epithelial ovarian cancer-treatment of recurrent disease

For women with advanced ovarian cancer, rates of response to first-line chemotherapy are high but most patients have relapses and become candidates for further chemotherapy. Chemotherapy for recurrence can palliate symptoms, and there is some evidence that it can also improve survival in this clinical situation. Patients who relapse quickly after first-line therapy should not be given the same drugs as were used initially. However, for patients who have longer intervals from treatment to relapse, the rates of response to a rechallenge with platinum are clinically significant. Several cytotoxic drugs have shown activity in patients whose disease has relapsed after therapy with platinum and a taxane; these drugs include topotecan, etoposide, pegylated liposomal doxorubicin, epirubicin, gemcitabine, altretamine, oxali platin, and vinorelbine. Recurrent ovarian cancer is also an important setting in which to test investigational agents with promising activity, such as new platinum compounds, new taxanes, and other cytotoxic agents, as well as non-cytotoxic compounds with novel mechanisms of action.

Drug therapy for gynaecological cancer in older women

A substantial proportion of all women dying from gynaecological malignancies are aged >75 years. Many reports have indicated that the survival of these patients is decreased compared with younger patients. Differences in biological behaviour, stage of the disease at presentation, and reluctance to undergo aggressive treatment with its associated morbidity are among the factors thought to be responsible for this difference in outcomes. However, investigations also indicate that elderly patients may receive less surgical and chemotherapeutic treatment without obvious clinical rationale. This overview is aimed at providing a guideline of chemotherapy appropriate for patients with epithelial ovarian, uterine (corpus and cervix), and vulvar cancer, aged 70 to 75 years and over. Platinum-based chemotherapy is the cornerstone of drug treatment in patients with ovarian cancer. Patients aged between 70 and 75 years with a good performance status can be treated with cisplatin- or carboplatin-based chemotherapy. Carboplatin, either in combination or as a single-agent, may offer advantages in patients aged >75 years and in those with a poor performance status. For patients with early recurrence there is no standard treatment, but several cytostatic and hormonal agents can be used with palliative intent. Patients with a late recurrence are probably best retreated with a platinum-based regimen. In metastatic endometrial cancer, hormonal therapy is the first choice in tumours expressing a progesterone receptor. Poorly differentiated tumours infrequently respond to endocrine therapy. In this situation, and for patients with tumours that have become resistant to hormonal manipulation, platinum-based chemotherapy may be used. The use of carboplatin-based regimens seems preferable in elderly patients, particularly in those with a decreased performance status. The usefulness of chemotherapy in elderly patients with cervical cancer is limited. In case of recurrent or metastatic disease, the use of single agent (low-dose) cisplatin should be balanced against best supportive care. Although overall chemoradiation seems superior than radiotherapy alone in patients with locally advanced cervical cancer, the feasibility of this approach in elderly patients needs further investigation. Chemoradiation might also be considered in patients with locally advanced vulvar cancer. However, treatment-related morbidity can be considerable and randomised studies are lacking to prove a survival benefit. Our understanding of the tolerance and effectiveness of chemotherapy in elderly patients is still incomplete due to a paucity of trials that specifically focus on this subset of patients. However, there appears no argument to withhold chemotherapy based purely on age.

Oxaliplatin or paclitaxel in patients with platinum-pretreated advanced ovarian cancer: A randomized phase II study of the European Organization for Research and Treatment of Cancer Gynecology Group

PURPOSE

This was a multicentric, open, randomized, phase II study of single-agent paclitaxel and oxaliplatin to evaluate the efficacy of oxaliplatin in a relapsing progressive ovarian cancer patient population and to analyze the safety profile and impact of both agents on quality of life, time to progression, and survival.

PATIENTS AND METHODS

Eighty-six patients with platinum-pretreated advanced ovarian cancer were randomly assigned to two arms: 41 received paclitaxel at 175 mg/m(2) over 3 hours every 3 weeks, and 45 received oxaliplatin at 130 mg/m(2) over 2 hours every 3 weeks. For inclusion, patients had to have a performance status of 0 to 2 and to have received at least one and no more than two prior cisplatin- and/or carboplatin-containing chemotherapy regimens within the last 12 months.

RESULTS

Seven confirmed responses were observed in each arm, for an overall response rate in the total treated population of 17% (95% confidence interval [CI], 7% to 32%) in the paclitaxel arm and 16% (95% CI, 7% to 29%) in the oxaliplatin arm. Median time to progression was 14 weeks and 12 weeks, and overall survival was 37 weeks and 42 weeks in the paclitaxel and oxaliplatin arms, respectively. Among 63 patients with a 0- to 6-month progression-free, platinum-free interval, there were five objective responses with paclitaxel in 31 patients and two objective responses with oxaliplatin in 32 patients. Nine patients (22%) in the paclitaxel arm had grade 3 or 4 neutropenia (National Cancer Institute of Canada [NCIC] Common Toxicity Criteria). Two patients (4%) experienced grade 3 thrombocytopenia in the oxaliplatin arm. Maximum grade (grade 3) NCIC neurosensory toxicity was experienced by three patients (7%) in the paclitaxel arm and by four patients (9%) in the oxaliplatin arm.

CONCLUSION

Single-agent oxaliplatin at 130 mg/m(2) every 3 weeks is active with moderate toxicity in patients with cisplatin-/carboplatin-pretreated advanced ovarian cancer.

Development of a panel of 15 human ovarian cancer xenografts for drug screening and determination of the role of the glutathione detoxification system

OBJECTIVES

We have established a panel of 15 human ovarian cancer xenografts grown subcutaneously in the flank of the nude mouse. Similar to the clinic, the xenografts show differences in histological subtype and volume doubling time. We determined whether the panel is useful for drug screening by testing the sensitivity to six conventional anticancer agents. In addition, we investigated whether the glutathione detoxification system affects sensitivity to cisplatin and cyclophosphamide, major drugs in the treatment of ovarian cancer.

METHODS

Mice bearing well-established tumors were treated at maximum tolerated doses as defined by a reversible weight loss up to 15% of their initial weight: cisplatin 5 mg/kg iv weekly x2, cyclophosphamide 150 mg/kg ip 2-weekly x2, doxorubicin 8 mg/kg iv weekly x2, hexamethylmelamine ip 150 mg/kg every other day x4, methotrexate ip 150 mg/kg weekly x2, and 5-fluorouracil 60 mg/kg ip weekly x4. Glutathione levels and the activities of three different glutathione-dependent enzymes were measured in untreated xenograft tissues.

RESULTS

Growth inhibition >75% was reached for cisplatin in 40%, for cyclophosphamide in 27%, and for doxorubicin in 20% of the xenografts. Methotrexate and 5-fluorouracil did not induce growth inhibition of importance. Hexamethylmelamine showed >75% growth inhibition in 53% of the xenografts, which may have been caused by the favorable metabolism of the drug in mice when compared with that in patients. Glutathione levels varied 3.6-fold in the xenografts and did not show a relation with sensitivity to cisplatin, cyclophosphamide, or doxorubicin. No relation was found between the activities of glutathione S-transferase and glutathione peroxidase and the sensitivities to the three anticancer agents. Glutathione reductase activity, however, showed a weak, inverse relation with the efficacy of cisplatin and cyclophosphamide (r values of -0.55 and -0.58, respectively).

CONCLUSIONS

The sensitivity to the six anticancer agents of our panel of 15 human ovarian cancer xenografts reflects the response rates known for similar drugs in ovarian cancer patients. In that respect, the panel may be useful for drug screening as well as studies on the relevance of drug resistance features in vivo. The various components of the glutathione detoxification system did not predict for primary drug resistance which confirms clinical data in ovarian cancer.

Progress in ovarian cancer

The management of advanced ovarian cancer relies on appropriate surgical cytoreduction in conjunction with appropriate adjuvant chemotherapy. In the past year several studies have continued to support aggressive cytoreduction at the initial operation, including for stage IV disease, as well as in a second-look setting. Ongoing research has identified several agents active in ovarian cancer, yet the optimal first-line regimen has yet to be developed.