Chemotherapy for recurrent, metastatic, or persistent cervical cancer: a systematic review

Diagnosis, Therapy and Follow-up of Cervical Cancer. Guideline of the DGGG, DKG and DKH (S3-Level, AWMF Registry No. 032/033OL, May 2021) - Part 2 with Recommendations on Psycho-oncology, Rehabilitation, Follow-up, Recurrence, Palliative Therapy and Healthcare Facilities

Aim This is an update of the interdisciplinary S3-guideline on the Diagnosis, Therapy and Follow-up of Cervical Cancer (AWMF Registry No. 032/033OL), published in March 2021. The work on the updated guideline was funded by German Cancer Aid (Deutsche Krebshilfe) as part of the German Guideline Program in Oncology. The guideline was coordinated by the German Society of Gynecology and Obstetrics ( Deutsche Gesellschaft für Gynäkologie und Geburtshilfe , DGGG) and the Working Group on Gynecological Oncology ( Arbeitsgemeinschaft Gynäkologische Onkologie , AGO) of the German Cancer Society ( Deutsche Krebsgesellschaft , DKG). Method The process used to update the 2014 S3-guideline was based on an appraisal of the available evidence using the criteria of evidence-based medicine, adaptations of existing evidence-based national and international guidelines or - if evidence was lacking - on the consensus of the specialists involved in compiling the update. After an initial review of the current literature was carried out according to a prescribed algorithm, several areas were identified which, in contrast to the predecessor version from September 2014, required new recommendations or statements which would take account of more recently published literature and the recent appraisal of new evidence. Recommendations The short version of this guideline consists of recommendations and statements on palliative therapy and follow-up of patients with cervical cancer. The most important aspects included in this updated guideline are the new FIGO classification published in 2018, the radical open surgery approach used to treat cervical cancer up to FIGO stage IB1, and the use of the sentinel lymph node technique for tumors ≤ 2 cm. Other changes include the use of PET-CT, new options in radiotherapy (e.g., intensity-modulated radiotherapy, image-guided adaptive brachytherapy), and drug therapies to treat recurrence or metastasis.

The potential oncogenic and MLN4924-resistant effects of CSN5 on cervical cancer cells

Background

CSN5, a member of Cop9 signalosome, is essential for protein neddylation. It has been supposed to serve as an oncogene in some cancers. However, the role of CSN5 has not been investigated in cervical cancer yet.

Methods

Data from TCGA cohorts and GEO dataset was analyzed to examine the expression profile of CSN5 and clinical relevance in cervical cancers. The role of CSN5 on cervical cancer cell proliferation was investigated in cervical cancer cell lines, Siha and Hela, through CSN5 knockdown via CRISPR–CAS9. Western blot was used to detect the effect of CSN5 knockdown and overexpression. The biological behaviors were analyzed by CCK8, clone formation assay, 3-D spheroid generation assay and cell cycle assay. Besides, the role CSN5 knockdown in vivo was evaluated by xenograft tumor model. MLN4924 was given in Siha and Hela with CSN5 overexpression.

Results

We found that downregulation of CSN5 in Siha and Hela cells inhibited cell proliferation in vitro and in vivo, and the inhibitory effects were largely rescued by CSN5 overexpression. Moreover, deletion of CSN5 caused cell cycle arrest rather than inducing apoptosis. Importantly, CSN5 overexpression confers resistance to the anti-cancer effects of MLN4924 (pevonedistat) in cervical cancer cells.

Conclusions

Our findings demonstrated that CSN5 functions as an oncogene in cervical cancers and may serve as a potential indicator for predicting the effects of MLN4924 treatment in the future.

Identification of Chemo and Radio-Resistant Sub-Population of Stem Cells in Human Cervical Cancer HeLa Cells

BACKGROUND

Cervical cancer ranks the second female malignancy after breast cancer. Cancer stem cells (CSCs) are hard to be eradicated, so can recur. We aim to isolate and characterize CSCs from HeLa cells.

METHODS

These cells express clusters of differentiation (CDs), 44 and 24, to be sorted by fluorescence-activated cell sorting (FACS).

RESULTS

CD44⁺CD24⁺ cells showed potential to form spheres, tumorigenicity, stemness genes and higher resistance to cisplatin, X-ray.

CONCLUSION

CD44⁺CD24⁺ HeLa cells hold characteristics of CSCs, in vitro, in vivo studies, suggesting that targeting may lead to screening of new anti-cancer therapies.

Erlotinib overcomes paclitaxel-resistant cancer stem cells by blocking the EGFR-CREB/GRβ-IL-6 axis in MUC1-positive cervical cancer

Cancer stem cells (CSCs) are often enriched after chemotherapy and contribute to tumor relapse. While epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are widely used for the treatment of diverse types of cancer, whether EGFR-TKIs are effective against chemoresistant CSCs in cervical cancer is largely unknown. Here, we reveal that EGFR correlates with reduced disease-free survival in cervical cancer patients with chemotherapy. Erlotinib, an EGFR-TKI, effectively impedes CSCs enrichment in paclitaxel-resistant cells through inhibiting IL-6. In this context, MUC1 induces CSCs enrichment in paclitaxel-resistant cells via activation of EGFR, which directly enhances IL-6 transcription through cAMP response element-binding protein (CREB) and glucocorticoid receptor β (GRβ). Treatment with erlotinib sensitizes CSCs to paclitaxel therapy both in vitro and in vivo. More importantly, positive correlations between the expressions of MUC1, EGFR, and IL-6 were found in 20 cervical cancer patients after chemotherapy. Mining TCGA data sets also uncovered the expressions of MUC1-EGFR-IL-6 correlates with poor disease-free survival in chemo-treated cervical cancer patients. Collectively, our work has demonstrated that the MUC1-EGFR-CREB/GRβ axis stimulates IL-6 expression to induce CSCs enrichment and importantly, this effect can be abrogated by erlotinib, uncovering a novel strategy to treat paclitaxel-resistant cervical cancer.

Hypoalbuminemia is a Predictive Factor for Fistula Formation in Recurrent Cervical Cancer

OBJECTIVE

Antivascular endothelial growth factor monoclonal antibodies inhibit tumor angiogenesis, consequently impeding the recruitment of new vasculature to existing and new tumor lesions. We sought to evaluate toxicities in women with recurrent cervical cancer after receiving bevacizumab combination chemotherapy.

METHODS

A review was conducted of women with recurrent and metastatic cervical cancer who were treated with salvage chemotherapy with or without bevacizumab between 2005 and 2015. Clinicopathologic data and reasons for treatment discontinuation were recorded. Patients that were excluded had other histology than squamous or adenocarcinoma, received 1 cycle of salvage chemotherapy, single agent bevacizumab, currently on treatment, or noncompliant. Statistical analysis was performed using the Fishers Exact Test, logistic regression, and Kaplan-Meier Survival Analysis.

RESULTS

A total of 74 patients were included in analysis. Twenty-six patients were treated with bevacizumab (BEV) and chemotherapy and 48 patients with chemotherapy alone (chemotherapy). The progression free survival was significant with median 12 months versus 7 months for the BEV cohort (P<0.01) and the overall survival was a median 74 months versus 23 months for the BEV cohort (P=0.06). Cessation of treatment secondary to severe toxicities was seen in 46% (n=12) of BEV cohort versus 15% (n=7) of chemotherapy cohort (P<0.01). Twenty-seven percent (n=7) of patients in the BEV cohort stopped secondary because of fistula formations. Lower albumin levels and use of bevacizumab were identified as an independent predictor factors for fistula formation (P=0.004 and 0.024, respectively).

CONCLUSIONS

Hypoalbuminemia and bevacizumab treatments are significant predictive factors of fistula formation in patients treated for recurrent cervical cancer.

LGR5 promotes cancer stem cell traits and chemoresistance in cervical cancer

Cancer stem cells (CSCs), also known as tumor-initiating cells, contribute to tumorigenesis, resistance to chemoradiotherapy and recurrence in human cancers, suggesting targeting CSCs may represent a potential therapeutic strategy. Leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5) has recently been found to be a bona fide marker of colorectal CSCs. Our previous study showed that LGR5 functions as a tumor promoter in cervical cancer by activating the Wnt/β-catenin pathway. However, very little is known about the function or contribution of LGR5 to cervical CSCs. Here, we have modulated the expression of LGR5 using an overexpression vector or short hairpin RNA in cervical cancer cell lines. We demonstrated that elevated LGR5 expression in cervical cancer cells increased tumorsphere-forming efficiency; conferred chemoresistance to cisplatin treatment; augmented cell migration, invasion and clonogenicity; and elevated the levels of stem cell-related transcription factors in vitro. Furthermore, modulated LGR5⁺ cells, unlike LGR5^- cells, were highly tumorigenic in vivo. In addition, the modulated LGR5⁺ cells could give rise to both LGR5⁺ and LGR5^- cells in vitro and in vivo, thereby establishing a cellular hierarchy. Finally, we found that the increased tumorsphere-forming efficiency induced by LGR5 could be regulated through the inhibition or activation of the Wnt/β-catenin pathway in cervical cancer cells. Taken together, these results indicate that LGR5 has a vital oncogenic role by promoting cervical CSC traits and may represent a potential clinical target.

Empirical evidence against placebo controls

The revised Declaration of Helsinki allows placebo-controlled trials to be used even when there is an established therapy, provided there are adequate 'methodological' reasons for doing so. This seems to violate the principle of beneficence: where there is an established therapy, physicians treating patients with a placebo are withholding a known effective therapy. Because of this problem, we hypothesised that clinical researchers may be unwilling to risk violating the principle of beneficence and employ placebo-controlled trials in cases where there is an established therapy. In this paper, we began to investigate this hypothesis. After summarising the arguments for and against using placebo controls in clinical practice, we exploredthe extent to which placebo-controlled trials are used in cases where there is an established therapy. To do this, we conducted as systematic search for all placebo-controlled trials published in 2015 in the five highest impact general medical journals. We identified 70 placebo-controlled trials. Of these, 66 were for indications where there was no established effective therapy. Only four used a placebo control in spite of there being an available effective therapy. The infrequent use of placebo controlled trials where established therapy exists highlights a seeming discrepancy between what the Declaration of Helsinki allows and what clinical investigators believe to be ethically acceptable. The evidence presented in this paper suggests that the Declaration of Helsinki be reconsidered, and perhaps revised, in light of actual practice.

Prognostic factors from a randomized phase III trial of paclitaxel and carboplatin versus paclitaxel and cisplatin in metastatic or recurrent cervical cancer: Japan Clinical Oncology Group (JCOG) trial: JCOG0505-S1

PURPOSE

The Japan Clinical Oncology Group (JCOG) trial JCOG0505 demonstrated the statistically significant non-inferiority of paclitaxel plus carboplatin (TC) to paclitaxel plus cisplatin (TP) in terms of overall survival (OS) in metastatic or recurrent cervical cancer. In that trial, patients were randomly assigned, adjusting for institution and known prognostic factors. The objective of this ancillary study was to evaluate the appropriateness of the adjustment factors used to have randomly assigned treatments and to investigate new potentially useful prognostic factors of paclitaxel plus platinum for future randomized trials in metastatic or recurrent cervical cancer.

METHODS

The study subjects comprised 244 eligible patients in the JCOG0505 who were merged to have received either TC or TP. The effects of the following factors on OS were investigated using a Cox regression model taking into consideration the adjustment factors used in randomization in this trial (e.g., performance status [PS]) and other baseline factors, including platinum-free interval (PFI), pretreatment hemoglobin levels (PHLs), and pretreatment platelet counts (PPCs).

RESULTS

The median follow-up was 17.6 months, and median OS was 18.0 months. The hazard ratio was 1.83 in patients with a PS of 1 or 2 (vs. 0; P = 0.0004; 95 % confidence interval [CI] 1.31-2.55), 2.92 in patients with a PFI of <6 months (vs. PFI of ≥12 months; P < 0.0001; 95 % CI 1.73-4.91), 2.09 in patients with a PFI of <12 months (vs. PFI of ≥12 months; P = 0.0034; 95 % CI 1.28-3.44), and 0.69 in patients with PHL higher than or equal to the median value (vs. less than the median; P = 0.016; 95 % CI 0.51-0.93). No significant differences were obtained for PPC or the other known factors.

CONCLUSIONS

In addition to the known prognostic factor of PS, which was used as an adjusting factor, a PFI of <12 months and lower PHL were newly demonstrated to be associated with poor outcomes in patients with metastatic or recurrent cervical cancer. These new prognostic factors should be validated in future prospective trials.

CLINICAL TRIAL INFORMATION

UMIN-CTR[ http://www.umin.ac.jp/ctr/ ] ID: C000000335.

Effect of changes in treatment practice on survival for cervical cancer: results from a population-based study in Manitoba, Canada

BACKGROUND

Results from clinical trials in the 1990s led to changes in the recommended treatment for the standard therapy for stage IIB-IVA cervical cancer from radiotherapy alone to chemo-radiotherapy. We conducted the first population-based study in Canada to investigate temporal treatment patterns for cervical cancer and long-term survival in relation to these changes in the treatment guidelines.

METHODS

Detailed information on stage and treatment for 1085 patients diagnosed with cervical cancer in 1984-2008 and identified from the population-based Manitoba Cancer Registry (MCR) in Canada was obtained from clinical chart review and the MCR. Factors associated with receiving guideline treatment were identified using logistic regression. All cause and cervical cancer specific survival were compared in patients who were and were not treated as recommended in the guidelines, using Cox proportional hazards models.

RESULTS

The median follow-up time was 6.4 years (range: 0.05-26.5 years). The proportion of women who received guideline treatment was 79 % (95 % confidence interval [CI]: 76-81 %). However, the likelihood of being treated according to the guidelines over time was modified by age (p < 0.0001) and tumour stage at diagnosis (p = 0.002). Women who were treated according to the guidelines after the change in recommended clinical practice (1999-2008) had a significantly lower risk of death from all causes and from cervical cancer. This was driven by lower mortality rates in cases with stage IIB-IVA tumours (all causes of death: hazard ratio [HR] = 0.60, 95 % CI: 0.43-0.82, p = 0.002; cervical cancer related death: HR = 0.64, 95 % CI: 0.44-0.93, p = 0.02).

CONCLUSIONS

The management of cervical cancer patients in Manitoba, Canada was in good agreement with treatment guidelines although reasons for departure from the guideline recommendations could not be examined further due to lack of data. Treatment of stage IIB-IVA cervical cancers with recommended concurrent chemo-radiotherapy, which is now standard practice, was associated with substantially increased survival, although the effect of changes in clinical practice including maintenance of haemoglobin levels on improved survival cannot be ruled out as a contributing factor.

Targeted PI3K/AKT/mTOR therapy for metastatic carcinomas of the cervix: A phase I clinical experience

Background

Activated PI3K/AKT/mTOR pathway frequently occurs in metastatic or recurrent cervical carcinomas. However, the clinical benefits of matched therapy, a therapeutic approach targeting a specific mutational abnormality, have not yet been established.

Methods

We analyzed the outcomes of patients with metastatic or recurrent cervical carcinomas who had a test for PIK3CA mutation and/or PTEN loss/mutation, and received ≥1 phase I therapeutic regimen between January 2006 and June 2013.

Results

Patients with adenocarcinoma had fewer PIK3CA mutations (14%), and survived longer (median, 14.2 months) than those with squamous cell carcinoma (48% and 7.2 months; p = 0.016, and 0.001, respectively). Matched therapy targeting the activated PI3K/AKT/mTOR pathway led to a favorable rate of SD ≥ 6 months/CR/PR (53%) and significantly longer progression-free survival (median, 6.0 months) than non-matched therapy (11% and 1.5 months; p = 0.08 and 0.026; respectively). In patients with squamous cell carcinoma of the cervix, the presence of PIK3CA mutations was associated with a significantly longer overall survival (median, 9.4 months) than the absence of PIK3CA mutations (median, 4.2 months; p = 0.019).

Conclusions

Matched therapy targeting the activated PI3K/AKT/mTOR pathway provided meaningful clinical benefits. Thus, further evaluation of PI3K/AKT/mTOR pathway targeted therapy is warranted, especially in metastatic or recurrent squamous cell carcinoma.

Systemic therapy for recurrent, persistent, or metastatic cervical cancer: a clinical practice guideline

BACKGROUND

Systemic therapy options are needed for women with recurrent, metastatic, or persistent cervical cancer. This systematic review and clinical practice guideline were developed to address that need, and to update a 2007 guideline from Cancer Care Ontario's Program in Evidence-Based Care.

METHODS

The literature between 2006 and April 2014 in the medline and embase databases, the Cochrane Database of Systematic Reviews (Issue 4, 2014), the Cochrane Central Register of Controlled Trials (Issue 3, 2014), relevant guideline databases, and conference proceedings of the American Society of Clinical Oncology (2007-2013) was searched. A working group developed draft guidelines and incorporated comments and feedback from internal and external reviewers.

RESULTS

Four phase iii randomized controlled trials met the inclusion criteria for the review and provided the basis for draft recommendations. Feedback was obtained from Ontario practitioners and others abroad, which led to modifications to the draft recommendations. Three key recommendations were developed.

CONCLUSIONS

The working group concluded that all patients should be offered the opportunity to participate in appropriate randomized clinical trials. Cisplatin-paclitaxel, cisplatin-vinorelbine, cisplatin-gemcitabine, and cisplatin-topotecan are recommended combinations for this patient population. The substitution of carboplatin for cisplatin in the foregoing combinations can also be recommended because carboplatin is associated with fewer adverse effects and greater ease of administration. Selection of combination chemotherapy will depend on the toxicity profile, patient preference, and other factors. Finally, bevacizumab in combination with cisplatin-paclitaxel or carboplatin-paclitaxel is recommended for a specific subset of the target population as outlined in Gynecologic Oncology Group study 0240.

Temporal trends in the relative survival among women with cervical cancer in Canada: a population-based study

OBJECTIVE

Cervical cancer was estimated to affect approximately 1300 women in Canada in 2011, and 350 women were expected to die from this disease. We estimated the trends in the relative survival ratio for patients diagnosed with epithelial invasive cervical cancer in Canadian population during the period 1992-2005.

METHODS

A flexible parametric model was used to estimate the relative survival ratio. Relative survival ratio is defined as the observed survival among patients with cancer divided by the expected survival in the general population. We incorporated age group, histology of tumor, geographical region, and year of diagnosis in the model to predict 2- and 5-year relative survival ratios.

RESULTS

A total of 13,424 patients with a diagnosis of epithelial invasive cervical cancer were included in this analysis, whose mean (SD) age was 49.3 (16.0) years at the time of diagnosis. The histologic classification of the cervical tumor was squamous for 75.4% of the cases followed by glandular for 18.5% of the cases. Other epithelial tumors accounted for 6.2% of the cases. The same pattern was observed for all regions. The glandular and the "other epithelial" cancers had the best and worst survival, respectively. Fifty percent of all cases were diagnosed in Ontario.

CONCLUSIONS

This article indicates gradual improvements for relative survival ratio for all age groups, all types of tumor, and all geographical regions in Canada during the 1992-2005 period. The improvements may be related to evolutions in screening, diagnosis, and treatment. Further progress may be achieved by extending the screening coverage, possibly changing the screening test, or advances in treatment.

Topotecan for the treatment of recurrent and stage IVB carcinoma of the cervix

This paper presents a summary of the evidence review group (ERG) report into the clinical effectiveness and cost-effectiveness of topotecan in combination with cisplatin for the treatment of recurrent and stage IVB carcinoma of the cervix, in accordance with the licensed indication, based upon the evidence submission from the manufacturer to the National Institute for Health and Clinical Excellence (NICE) as part of the single technology appraisal (STA) process. The outcomes measured were overall survival, progression-free survival, response rates, adverse effects of treatment, health-related quality of life (HRQoL) and quality-adjusted life-years (QALYs) gained. The manufacturer stated that topotecan plus cisplatin is the only combination regimen to date to have demonstrated a statistically significant survival advantage compared to cisplatin monotherapy in the licensed population. The clinical evidence came from three clinical trials comparing topotecan plus cisplatin with cisplatin monotherapy (GOG-0179), topotecan plus cisplatin with paclitaxel plus cisplatin (GOG-0169), and four cisplatin-based combination therapies: topotecan plus cisplatin, paclitaxel plus cisplatin, gemcitabine plus cisplatin, and vinorelbine plus cisplatin (GOG-0204). Results from GOG-0179 showed greater median overall survival with topotecan plus cisplatin than with cisplatin monotherapy: 9.4 months versus 6.5 months. Similar results were also reported for median progression-free survival. Response rates also showed an advantage with topotecan plus cisplatin compared with cisplatin monotherapy. The response rates in patients receiving cisplatin monotherapy were very low, but the potential reasons for this were not discussed in the manufacturer’s submission. Patients receiving topotecan plus cisplatin experienced a greater number of adverse events and the ERG was concerned with some of the assumptions related to HRQoL. In the base-case direct comparison, the incremental cost-effectiveness ratio (ICER) of topotecan plus cisplatin versus cisplatin monotherapy was £17,974 per QALY in the main licensed population, £10,928 per QALY in the cisplatin-naive population (including stage IVB patients) and £32,463 per QALY in sustained cisplatin-free interval patients. In response to the point for clarification raised by the ERG, the manufacturer submitted a revised indirect comparison incorporating HRQoL and a longer time horizon. Where the hazard ratio derived from GOG-0169 was employed, paclitaxel plus cisplatin was dominated by topotecan plus cisplatin, but, where the hazard ratio from GOG-0204 was adopted, paclitaxel plus cisplatin was found to have an ICER of £13,260 per QALY versus topotecan plus cisplatin. At present there is a paucity of evidence available on the clinical effects of topotecan plus cisplatin and the effects of palliative treatment in general for women with advanced and recurrent carcinoma of the cervix. Further trials, or the implementation of registries, are required to establish the efficacy and safety of topotecan plus cisplatin. The guidance issued by NICE in September 2009 as a result of the STA states that topotecan in combination with cisplatin is recommended as a treatment option for women with recurrent or stage IVB cervical cancer, only if they have not previously received cisplatin. Women who have previously received cisplatin and are currently being treated with topotecan in combination with cisplatin for the treatment of cervical cancer should have the option to continue therapy until they and their clinicians consider it appropriate to stop.

National Academy of Clinical Biochemistry Laboratory Medicine Practice Guidelines for use of tumor markers in liver, bladder, cervical, and gastric cancers

BACKGROUND

Updated National Academy of Clinical Biochemistry Laboratory Medicine Practice Guidelines for the use of tumor markers in the clinic have been developed.

METHODS

Published reports relevant to use of tumor markers for 4 cancer sites--liver, bladder, cervical, and gastric--were critically reviewed.

RESULTS

Alpha-fetoprotein (AFP) may be used in conjunction with abdominal ultrasound for early detection of hepatocellular carcinoma (HCC) in patients with chronic hepatitis or cirrhosis associated with hepatitis B or C virus infection. AFP concentrations >200 microg/L in cirrhotic patients with typical hypervascular lesions >2 cm in size are consistent with HCC. After a diagnosis of HCC, posttreatment monitoring with AFP is recommended as an adjunct to imaging, especially in the absence of measurable disease. Although several urine markers have been proposed for bladder cancer, none at present can replace routine cystoscopy and cytology in the management of patients with this malignancy. Some may, however, be used as complementary adjuncts to direct more effective use of clinical procedures. Although carcinoembryonic antigen and CA 19-9 have been proposed for use gastric cancer and squamous cell carcinoma antigen for use in cervical cancer, none of these markers can currently be recommended for routine clinical use.

CONCLUSIONS

Implementation of these recommendations should encourage optimal use of tumor markers for patients with liver, bladder, cervical, or gastric cancers.

Stabilization of mismatch repair gene PMS2 by glycogen synthase kinase 3beta is implicated in the treatment of cervical carcinoma

Background

PMS2 expression loss was reported in a variety of human. However, its importance has not been fully understood in cervical carcinoma. The aim of this study was to determine the expression of PMS2 in cervical carcinoma and evaluate the significance of mismatch repair gene PMS2 regulated by glycogen synthase kinase 3β (GSK-3β) in chemosensitivity.

Methods

We examined PMS2 and phosphorylated GSK-3β(s9) expression in cervical carcinoma tissues using immunohistochemical staining. Furthermore, we detected PMS2 expression in HeLa cells and evaluate the interaction with GSK-3β after transfection with GSK-3β by small interference RNA (siRNA), co-immunoprecipitation and immunoblotting. We also evaluated the effect of PMS2 transfection on HeLa cells' chemosensitivity to cisplatin treatment.

Results

We found significant downregulation of PMS2 in cervical carcinoma, which was negatively associated with phosphorylated GSK-3β (s9). Furthermore, we demonstrated GSK-3β transfection was able to interact with PMS2 and enhance PMS2 production in HeLa cells, and increased PMS2 production was responsible for enhanced chemosensitivity.

Conclusions

Our results provide the evidence that stabilization of PMS2 production by GSK-3β was important to improve chemosensitization, indicating the significance of GSK-3β-related PMS2 downregulation in the development of cervical carcinoma and in developing a potential strategy for chemotherapy.

EGFR and HER2 expression in primary cervical cancers and corresponding lymph node metastases: implications for targeted radiotherapy

Background

Proteins overexpressed on the surface of tumor cells can be selectively targeted. Epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) are among the most often targeted proteins. The level and stability of expression in both primary tumors and corresponding metastases is crucial in the assessment of a receptor as target for imaging in nuclear medicine and for various forms of therapy. So far, the expression of EGFR and HER2 has only been determined in primary cervical cancers, and we have not found published data regarding the receptor status in corresponding metastatic lesions. The goal of this study was to evaluate whether any of these receptors are suitable as target for clinical diagnosis and therapy.

Methods

Expression of EGFR and HER2 was investigated immunohistochemically in both lymph node metastases and corresponding primary cervical cancers (n = 53). HER2 and EGFR expression was scored using HercepTest criteria (0, 1+, 2+ or 3+).

Results

EGFR overexpression (2+ or 3+) was found in 64% (35/53) of the primary cervical tumors and 60% (32/53) of the corresponding lymph node metastases. There was a good concordance between the primary tumors and the paired metastases regarding EGFR expression. Only four patients who had 2+ or 3+ in the primary tumors changed to 0 or 1+ in lymph node metastases, and another two cases changed the other way around. None of the primary tumors or the lymph node metastases expressed HER2 protein.

Conclusion

The EGFR expression seems to be common and stable during cervical cancer metastasis, which is encouraging for testing of EGFR targeted radiotherapy. HER2 appears to be of poor interest as a potential target in the treatment of cervical cancer.

On reporting results from randomized controlled trials with recurrent events

BACKGROUND

Evidence-based medicine has been advanced by the use of standards for reporting the design and methodology of randomized controlled trials (RCT). Indeed, without this information it is difficult to assess the quality of evidence from an RCT. Although a variety of statistical methods are available for the analysis of recurrent events, reporting the effect of an intervention on outcomes that recur is an area that remains poorly understood in clinical research. The purpose of this paper is to outline guidelines for reporting results from RCTs where the outcome of interest is a recurrent event.

METHODS

We used a simulation study to relate an event process and results from analyses of the gamma-Poisson, independent-increment, conditional, and marginal Cox models. We reviewed the utility of regression models for the rate of a recurrent event by articulating the associated study questions, preenting the risk sets, and interpreting the regression coefficients.

RESULTS

Based on a single data set produced by simulation, we reported and contrasted results from statistical methods for evaluating treatment effect from an RCT with a recurrent outcome. We showed that each model has different study questions, assumptions, risk sets, and rate ratio interpretation, and so inferences should consider the appropriateness of the model for the RCT.

CONCLUSION

Our guidelines for reporting results from an RCT involving a recurrent event suggest that the study question and the objectives of the trial, such as assessing comparable groups and estimating effect size, should determine the statistical methods. The guidelines should allow clinical researchers to report appropriate measures from an RCT for understanding the effect of intervention on the occurrence of a recurrent event.