A feasibility study of topotecan with standard-dose cisplatin and concurrent primary radiation therapy in locally advanced cervical cancer

Novel agents and treatment techniques to enhance radiotherapeutic outcomes in carcinoma of the uterine cervix

BACKGROUND

Survival of patients with locally advanced carcinoma cervix (LACC) using the current standard of concurrent chemo-radiotherapy (CCRT) has reached a plateau over the last two decades. Loco-regional failure in first two years of treatment completion and distant metastasis in the subsequent years has put the survival curves at a halt. Strategies of induction and adjuvant chemotherapy have yielded little as has any advancement in techniques of delivery of radiation therapy. This article aims at discussing the current existing literature as well as promising novel strategies to enhance radiotherapeutic outcomes in carcinoma of the uterine cervix.

METHODS

The review of English literature included phase I-III trials evaluating either a novel agent, novel application/modifications of an existing treatment regimen or an innovative treatment technique. The studies have been divided in to subsections with summary of most important findings at the end of each section.

RESULTS

Despite CCRT being the 'gold standard' treatment, several issues like optimum drug combination, schedule of drug delivery, combination with molecular targeted agents etc. remain undefined. Taxane, topoisomerase and gemcitabine based regimen needs to be further explored and compared with cisplatin based CCRT regimen. Several approaches like local delivery of cytotoxic agents, use of nano-medicine with CCRT are appearing on horizon with promises for the future. Therapies need to be designed based on the human papillomavirus titers of the patients and incorporation of radiosensitizers as an effective way of palliation with short course of radiotherapy may further enhance the radiotherapeutic outcomes.

CONCLUSIONS

The results of the studies with novel agents and treatment techniques appear promising. Further research in this arena including incorporation of cost-effectiveness analysis and quality of life issues in future trial designs are warranted.

In vitro chemoresponse analysis of cervical cancer patient specimens

PURPOSE

The objective of this study was to report the results of in vitro chemoresponse analysis of primary, metastatic, and recurrent human cervical cancers.

METHODS

There were 557 tumor specimens submitted for testing from August 2006 to June 2010. Single agents tested were cisplatin, carboplatin, paclitaxel, docetaxel, epirubicin, fluorouracil, 4-hydroxy ifosfamide (active metabolite of ifosfamide), SN-38 (active metabolite of irinotecan), topotecan, and vinorelbine. Doublets tested were carboplatin/paclitaxel and cisplatin/topotecan. Tumor response was determined from dose-response curves. Results were scored as responsive, intermediate, or nonresponsive. Chemoresponse was reported as the combined responsive and intermediate results.

RESULTS

Three hundred fifty-three (63.4%) of 557 submitted specimens were successfully assayed. Confirmation of histology and tumor status (primary, metastatic, or recurrent) was available for 273 specimens. The chemoresponse of the most active agents in primary cancers (n = 151) was 75% for SN-38, 71% for 4-hydroxy ifosfamide, 62% for topotecan, and 73% for carboplatin/paclitaxel. The chemoresponse of metastatic cancers (n = 66) was 54% for SN-38, 51% for 4-hydroxy ifosfamide, 44% for epirubicin, and 53% for carboplatin/paclitaxel. The chemoresponse for recurrent cancers (n = 56) was 44% for epirubicin, 41% for 4-hydroxy ifosfamide, 39% for vinorelbine, 39% for paclitaxel, 36% for topotecan, 46% for carboplatin/paclitaxel, and 35% for cisplatin/topotecan. The overall chemoresponse was greater in primary cancers (58%) than in recurrent cancers (35%) (P < 0.0001).

CONCLUSIONS

In vitro chemoresponse analysis of cervical cancer biospecimens is feasible. Chemoresponse results are variable depending on tumor status. Clinical studies of assay-directed therapy should be developed.

[Current methods of chemoradiotherapy for locally advanced cervical cancer. Options for reduction of side-effects]

The advantages of cisplatin based radiochemotherapy have been proven for over one and a half decades, particularly in the treatment of advanced solid tumours. In head and neck, and cervical tumours results of prospective studies are available. Those showed that both in the early and advanced stages, local control and overall survival rates are better than radiotherapy alone. The effect of cisplatin can be probably intensified with novel, more effective molecules, such as m-TOR inhibitors and tirapazamine. The authors review cisplatin and non-cisplatin based radiochemotherapy protocols, which improve previous treatment results. It should be considered, however, radiotherapy for cervical cancer can cause hematological, urogenital and intestinal toxicity, similarly to other combined treatments. The authors briefly outline international recommendations and their own experience for the prevention of these side-effects.

Novel approaches for concurrent irradiation in locally advanced cervical cancer: platinum combinations, non-platinum-containing regimens, and molecular targeted agents

Despite the available prevention and early detection strategies, squamous-cell carcinoma of the uterine cervix is still diagnosed as locally advanced disease in a considerable proportion of patients. As a potent sensitizer of cancer cells, cisplatin has been the "traditional partner" of external beam irradiation in this setting for more than two decades. Induction chemotherapy strategies followed by concurrent chemoradiation or surgery and preoperative concurrent chemoradiation have been recently implemented in clinical trials in an effort to optimize local control and to minimize the risk of distant metastases. In this context, cisplatin has been combined with a number of other potential radiosensitizers, including 5-fluorouracil, capecitabine, and gemcitabine. In patients resistant or intolerant to platinum compounds, numerous non-platinum-containing regimens have been developed, implementing various antimetabolites, taxanes, antineoplastic antibiotics, and topoisomerase II inhibitors. More recently, molecular agents targeting critical pathways in cervical malignant transformation are being assessed in early clinical trials in combination with external-beam irradiation. In the current work, we review the evolving role of cisplatin and other platinum compounds, either alone or in combination regimens, in the context of other potent radiosensitizers. The emerging role of molecular targeted agents, as candidate partners of external beam irradiation, is also discussed.

A phase I study of concurrent weekly topotecan and cisplatin chemotherapy with whole pelvic radiation therapy in locally advanced cervical cancer: a gynecologic oncology group study

PURPOSE

To determine the maximum tolerated dose (MTD) and acute dose-limiting toxicities (DLT) of intravenous topotecan administered with weekly cisplatin during pelvic radiation therapy in patients with locally advanced cervical cancer.

METHODS

Patients were treated at one of two dose levels receiving intravenous topotecan at 0.5mg/m(2) and cisplatin at either 30 or 40 mg/m(2) given weekly for 6 weeks concurrently with pelvic radiation and intracavitary brachytherapy. The primary endpoint for the escalation study was acute dose-limiting toxicities occurring within 30 days of completing radiation therapy.

RESULTS

Eleven patients were enrolled. Dose-limiting toxicity consisting of Grade 3 nausea and vomiting lasting >24h in one patient and grade 3 febrile neutropenia in another patient occurred at the first dose level of weekly topotecan 0.5mg/m(2) and cisplatin 40 mg/m(2). This necessitated de-escalation to weekly cisplatin 30 mg/m(2) in combination with topotecan 0.5mg/m(2) and pelvic radiation. This dose level was tolerable in 6 evaluable patients with only one DLT consisting of grade 4 thrombocytopenia, grade 3 abdominal pain and grade 3 elevated gamma glutamyl transpeptidase (GGT).

CONCLUSIONS

In women with locally advanced cervical cancer, intravenous topotecan 0.5mg/m(2) and cisplatin 30 mg/m(2) given weekly for 6 weeks with concurrent pelvic radiation and intracavitary brachytherapy were tolerable. Further expansion of the feasibility cohort of this study was suspended based on the results of a phase 3 trial comparing the efficacy of platinum combinations in advanced and recurrent cervical cancer.

Exenteration as a primary treatment for locally advanced cervical cancer: long-term results and prognostic factors

OBJECTIVE

Whereas pelvic exenteration is an established therapy for the treatment of recurrent cervical carcinoma, it is not often performed for primary locally advanced cervical cancer (LACC).

STUDY DESIGN

This retrospective study analyzed survival data and prognostic factors of 35 patients with LACC who were treated by pelvic exenteration.

RESULTS

After surgery, 33 patients (97%) were macroscopically free of tumor. In 20 patients, pelvic lymph nodes (LN) were involved, and in 6 of these, metastatic tissue had reached the paraaortal nodes. Overall, the patients' mean 5 year survival was 43%, and the median survival time was 30 months; these values ranged from 15% to 70% and from 15 to 44 months, respectively, depending on LN involvement (P=.006). Pelvic LN involvement was the only significant factor for overall survival found in the multivariate analysis (P=.02).

CONCLUSION

In LACC with free LNs and no distant metastases, pelvic exenteration has good long-term results.

Pathway profiling and rational trial design for studies in advanced stage cervical carcinoma: a review and a perspective

Multiple genetic abnormalities will have occurred in advanced cervical cancer and multiple targeting is likely to be needed to control tumor growth. To date, dominant therapeutic targets under scrutiny for cervical cancer treatment have been EGFR pathway and angiogenesis inhibition as well as anti-HPV vaccines. The potentially most effective targets to be blocked may be downstream from the membrane receptor or at the level of the nucleus. Alterations of the pathways involved in DNA repair and in checkpoint activations, as well as the specific site of HPV genome integration, appear worth assessing. For genetic mutational analysis, complete exon sequencing may become the norm in the future but at this stage frequent mutations (that matter) can be verified by PCR analysis. A precise documentation of relevant alterations of a large spectrum of protein biomarkers can be carried out by reverse phase protein array (RPPA) or by multiplex analysis. Clinical decision-making on the drug(s) of choice as a function of the biological alteration will need input from bio-informatics platforms as well as novel statistical designs. Endpoints are yet to be defined such as the loss (or reappearance) of a predictive biomarker. Single or dual targeting needs to be explored first in relevant preclinical animal and in xenograft models prior to clinical deployment.

Normal tissue complication probability modeling of acute hematologic toxicity in cervical cancer patients treated with chemoradiotherapy

PURPOSE

To test the hypothesis that increased pelvic bone marrow (BM) irradiation is associated with increased hematologic toxicity (HT) in cervical cancer patients undergoing chemoradiotherapy and to develop a normal tissue complication probability (NTCP) model for HT.

METHODS AND MATERIALS

We tested associations between hematologic nadirs during chemoradiotherapy and the volume of BM receiving≥10 and 20 Gy (V10 and V20) using a previously developed linear regression model. The validation cohort consisted of 44 cervical cancer patients treated with concurrent cisplatin and pelvic radiotherapy. Subsequently, these data were pooled with data from 37 identically treated patients from a previous study, forming a cohort of 81 patients for normal tissue complication probability analysis. Generalized linear modeling was used to test associations between hematologic nadirs and dosimetric parameters, adjusting for body mass index. Receiver operating characteristic curves were used to derive optimal dosimetric planning constraints.

RESULTS

In the validation cohort, significant negative correlations were observed between white blood cell count nadir and V10 (regression coefficient (β)=-0.060, p=0.009) and V20 (β=-0.044, p=0.010). In the combined cohort, the (adjusted) β estimates for log (white blood cell) vs. V10 and V20 were as follows: -0.022 (p=0.025) and -0.021 (p=0.002), respectively. Patients with V10≥95% were more likely to experience Grade≥3 leukopenia (68.8% vs. 24.6%, p<0.001) than were patients with V20>76% (57.7% vs. 21.8%, p=0.001).

CONCLUSIONS

These findings support the hypothesis that HT increases with increasing pelvic BM volume irradiated. Efforts to maintain V10<95% and V20<76% may reduce HT.

Locally advanced cervical cancer: what is the standard of care?

PURPOSE OF REVIEW

Carcinoma of the cervix remains a significant health problem for women worldwide. Locally advanced cervical cancer (LACC) is a common presentation that has been extensively studied in the last three decades. This article reviews the standard of care and discusses current topics of clinical research.

RECENT FINDINGS

A multidisciplinary approach to the treatment of cervical cancer has led to marked improvement in outcome. Main advances are with neoadjuvant chemotherapy, chemoradiation, and preventive vaccination. Concurrent chemoradiation with a platinum-based agent is the recommended treatment for LACC. Palliation with platinum agent remains the standard of care for inoperable patients who have metastatic or recurrent disease.

SUMMARY

This is a review of published and ongoing studies testing multidisciplinary and medical management of LACC, with a focus on newer chemotherapeutic approaches. Optimal multidisciplinary treatment planning improves the outcome of each patient diagnosed with cervical cancer.

Pharmacotherapy options for locally advanced and advanced cervical cancer

Cervical cancer continues to be a significant health burden worldwide. Globally, the majority of cancers are locally advanced at diagnosis; hence, radiation remains the most frequently used therapeutic modality. Currently, the value of adding cisplatin or cisplatin-based chemotherapy to radiation for the treatment of locally advanced cervical cancer is strongly supported by randomized studies and meta-analyses. Nevertheless, despite these significant achievements, therapeutic results are far from optimal; thus, novel therapies need to be investigated. A recent, randomized, phase III trial has shown for the first time that combination chemotherapy with cisplatin and gemcitabine concurrently with radiation improves parameters of survival over cisplatin alone and establishes a new standard for the management of locally advanced cervical cancer. On the other hand, advanced disease, presenting either as an International Federation of Gynecology and Obstetrics (FIGO) stage IVB or as persistent or recurrent to primary therapy without local curative options, remains a devastating group of diseases with no options other than palliative chemotherapy. Recent results from the GOG (Gynecologic and Oncologic Group)-204 study demonstrate that cisplatin-doublets with paclitaxel, vinorelbine, gemcitabine or topotecan only produce small improvements in survival, although with different toxicity patterns; hence, patient-related factors are important when choosing any one of these regimens. The role of targeted therapies both in locally advanced and advanced disease is promising, but still at an investigational stage.