Patient preferences for attributes of primary surgical debulking versus neoadjuvant chemotherapy for treatment of newly diagnosed ovarian cancer

Patient and clinician priorities for information on treatment outcomes for advanced ovarian cancer: a Delphi exercise

OBJECTIVE

Patients with advanced ovarian cancer face a range of treatment options, and there is unwarranted variation in treatment decision-making between UK providers. Decision support tools that produce data on treatment outcomes as a function of individual patient characteristics, would help both patients and clinicians to make informed, preference- and values-based choices. However, data on treatment outcomes to include in such tools are lacking.

METHODS

Following a literature review, a questionnaire was designed for use in a Delphi process to establish which treatment outcomes are important to both patients and clinicians in decision-making for treatment for advanced ovarian cancer. Patient and clinician panels were established.

RESULTS

Following 2 Delphi rounds, consensus was achieved for 7/11 items in the patient panel and 8/11 items in the clinician panel. Consensus across both panels was achieved for inclusion of both overall survival and progression free survival as important items in the decision-making process, although there remained differences of opinion as to whether these should be presented as relative or absolute values.

CONCLUSION

Information needs for treatment decision-making in ovarian cancer differ between and within patient and clinician groups. Whilst overall survival and progression free survival are universally accepted as important data items, decision support tools will need to be nuanced to allow presentation of a range of outcomes and associated probabilities, and in a range of formats, that can be tailored to the preferences of clinician and patients.

Gynaecological cancer surveillance for women with Lynch syndrome: systematic review and cost-effectiveness evaluation

Background

Lynch syndrome is an inherited condition which leads to an increased risk of colorectal, endometrial and ovarian cancer. Risk-reducing surgery is generally recommended to manage the risk of gynaecological cancer once childbearing is completed. The value of gynaecological colonoscopic surveillance as an interim measure or instead of risk-reducing surgery is uncertain. We aimed to determine whether gynaecological surveillance was effective and cost-effective in Lynch syndrome.

Methods

We conducted systematic reviews of the effectiveness and cost-effectiveness of gynaecological cancer surveillance in Lynch syndrome, as well as a systematic review of health utility values relating to cancer and gynaecological risk reduction. Study identification included bibliographic database searching and citation chasing (searches updated 3 August 2021). Screening and assessment of eligibility for inclusion were conducted by independent researchers. Outcomes were prespecified and were informed by clinical experts and patient involvement. Data extraction and quality appraisal were conducted and results were synthesised narratively. We also developed a whole-disease economic model for Lynch syndrome using discrete event simulation methodology, including natural history components for colorectal, endometrial and ovarian cancer, and we used this model to conduct a cost-utility analysis of gynaecological risk management strategies, including surveillance, risk-reducing surgery and doing nothing.

Results

We found 30 studies in the review of clinical effectiveness, of which 20 were non-comparative (single-arm) studies. There were no high-quality studies providing precise outcome estimates at low risk of bias. There is some evidence that mortality rate is higher for surveillance than for risk-reducing surgery but mortality is also higher for no surveillance than for surveillance. Some asymptomatic cancers were detected through surveillance but some cancers were also missed. There was a wide range of pain experiences, including some individuals feeling no pain and some feeling severe pain. The use of pain relief (e.g. ibuprofen) was common, and some women underwent general anaesthetic for surveillance. Existing economic evaluations clearly found that risk-reducing surgery leads to the best lifetime health (measured using quality-adjusted life-years) and is cost-effective, while surveillance is not cost-effective in comparison. Our economic evaluation found that a strategy of surveillance alone or offering surveillance and risk-reducing surgery was cost-effective, except for path_PMS2 Lynch syndrome. Offering only risk-reducing surgery was less effective than offering surveillance with or without surgery.

Limitations

Firm conclusions about clinical effectiveness could not be reached because of the lack of high-quality research. We did not assume that women would immediately take up risk-reducing surgery if offered, and it is possible that risk-reducing surgery would be more effective and cost-effective if it was taken up when offered.

Conclusions

There is insufficient evidence to recommend for or against gynaecological cancer surveillance in Lynch syndrome on clinical grounds, but modelling suggests that surveillance could be cost-effective. Further research is needed but it must be rigorously designed and well reported to be of benefit.

Study registration

This study is registered as PROSPERO CRD42020171098.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: NIHR129713) and is published in full in Health Technology Assessment; Vol. 28, No. 41. See the NIHR Funding and Awards website for further award information.

Preferences and considerations for interval cytoreductive surgery in advanced ovarian cancer: The patient's perspective

OBJECTIVE

Treatment of advanced-stage ovarian cancer contains cytoreductive surgery (CRS) and chemotherapy. Achieving successful CRS (≤ 1 cm residual disease) is prognostically important, but may not be feasible peri-operatively while still risking complications. Therefore, patients' treatment expectations are important to discuss. We investigated patient considerations for interval CRS.

METHODS

Patients with advanced-stage ovarian cancer planned for interval CRS completed a questionnaire about the impact of chance of successful CRS, survival benefit and becoming care-dependent on decision-making regarding CRS. The questionnaire included a vignette study, in which patients repeatedly chose between two treatment scenarios with varying levels for chance of successful CRS, survival benefit and risk of complications including stoma. Patient preferences were analyzed, including differences between patients aged < 70 and ≥ 70 years.

RESULTS

Among 85 included patients, 31 (37%) patients considered interval CRS worthwhile irrespective of survival benefit and 33 (39%) irrespective of chance of successful surgery. However, 34 patients (41%) considered interval CRS only worthwhile if survival benefit was > 12 months, while 41 (49%) thought so if chance of successful surgery was ≥ 25%. Older patients considered these factors more important. Overall, 27% considered becoming permanently dependent of home care unacceptable. In the vignette study (n = 72) risk of complications and stoma were considered less important than chance of successful CRS and survival benefit.

CONCLUSION

Survival benefit, chance of successful surgery and becoming care-dependent are important factors in patient's decision for interval CRS, while risk of complications and stoma are less important. Our results are useful in shared decision-making for interval CRS in ovarian cancer.

An overview of the current debate between using minimally invasive surgery versus laparotomy for interval cytoreductive surgery in epithelial ovarian cancer

The standard of care for treatment of advanced-stage epithelial ovarian cancer is primarily surgery followed by platinum-based chemotherapy, with the operative goal to achieve complete gross resection. Cytoreductive surgeries for epithelial ovarian cancer historically were performed via open laparotomy; however, as minimally invasive techniques became more widely accepted within gynecologic oncology, interest in employing this approach in the setting of cytoreductive surgery for epithelial ovarian cancer has grown. The purpose of this review was to examine the current debate between the use of minimally invasive surgery versus laparotomy as an approach to interval cytoreductive surgery in advanced epithelial ovarian cancer. While numerous retrospective and feasibility studies have found comparable outcomes with respect to complete gross residual disease, progression-free survival, and overall survival between minimally invasive and laparotomy approaches to interval cytoreductive surgery for epithelial ovarian cancer, methodological challenges limit the utility of these data. Given potential risks of underestimating disease burden and failing to achieve complete resection using a minimally invasive approach, further rigorous studies are needed to evaluate the safety and efficacy of minimally invasive surgery in this setting and to better define the subset of patients who would receive the greatest benefit from a minimally invasive approach.

Primary or Interval Debulking Surgery in Advanced Ovarian Cancer: a Personalized Decision-a Literature Review

PURPOSE OF REVIEW

Summarize the writings published in the last 5 years on the management of surgery in the first line of treatment for advanced ovarian cancer.

RECENT FINDINGS

For patients with a significant tumor burden, the neoadjuvant chemotherapy therapy (NACT) with interval debulking surgery (IDS) strategy shows comparable efficacy than primary debulking surgery (PDS) in terms of survival in randomized studies with less morbidity. Advanced epithelial ovarian cancer generates more than half cases a recurrence. First-line treatment is based on a chemotherapy regimen combining a platinum-based and a taxane-based, associated with surgery. This review considers papers of last 5 years of timing, thinking tools, and innovation in the management. The choice of strategy, PDS or IDS, would be a personalized recommendation. The challenge is to adapt the timing of the surgery to the patient's characteristics and that of her disease.

Association Between Overall Survival and the Tendency for Cancer Programs to Administer Neoadjuvant Chemotherapy for Patients With Advanced Ovarian Cancer

IMPORTANCE

Randomized clinical trials have found that, in patients with advanced-stage epithelial ovarian cancer, neoadjuvant chemotherapy has similar long-term survival and improved perioperative outcomes compared with primary cytoreductive surgery. Despite this, considerable controversy remains about the appropriate use of neoadjuvant chemotherapy, and the proportion of patients who receive this treatment varies considerably among cancer programs in the US.

OBJECTIVE

To evaluate the association between high levels of neoadjuvant chemotherapy administration and overall survival in patients with advanced ovarian cancer.

DESIGN, SETTING, AND PARTICIPANTS

This difference-in-differences comparative effectiveness analysis leveraged differential adoption of neoadjuvant chemotherapy in Commission on Cancer-accredited cancer programs in the US and included women with a diagnosis of stage IIIC and IV epithelial ovarian cancer between January 2004 and December 2015 who were followed up through the end of 2018. The data were analyzed between September 2020 and January 2021.

EXPOSURES

Treatment in a cancer program with high levels of neoadjuvant chemotherapy administration (more often than expected based on case mix) or in a program that continued to restrict its use after the 2010 publication of a clinical trial demonstrating the noninferiority of neoadjuvant chemotherapy compared with primary surgery for the treatment of patients with advanced ovarian cancer.

MAIN OUTCOMES AND MEASURES

Case mix-standardized median overall survival time and 1-year all-cause mortality assessed with a flexible parametric survival model.

RESULTS

We identified 19 562 patients (mean [SD] age, 63.9 [12.6] years; 3.2% Asian, 8.0% Black, 4.8% Hispanic, 82.5% White individuals) who were treated in 332 cancer programs that increased use of neoadjuvant chemotherapy from 21.7% in 2004 to 2009 to 42.2% in 2010 to 2015 and 19 737 patients (mean [SD] age, 63.5 [12.6] years; 3.1% Asian, 7.7% Black, 6.5% Hispanic, 81.8% White individuals) who were treated in 332 programs that marginally increased use of neoadjuvant chemotherapy (20.1% to 22.5%) over these periods. The standardized median overall survival times improved by similar magnitudes in programs with high (from 31.6 [IQR, 12.3-70.1] to 37.9 [IQR, 17.0-84.9] months; 6.3-month difference; 95% CI, 4.2-8.3) and low (from 31.4 [IQR, 12.1-67.2] to 36.8 [IQR, 15.0-80.3] months; 5.4-month difference, 95% CI, 3.5-7.3) use of neoadjuvant chemotherapy after 2010 (difference-in-differences, 0.9 months; 95% CI, -1.9 to 3.7). One-year mortality declined more in programs with high (from 25.6% to 19.3%; risk difference, -5.2%; 95% CI, -6.4 to -4.1) than with low (from 24.9% to 21.8%; risk difference, -3.2%, 95% CI, -4.3 to -2.0) use of neoadjuvant chemotherapy (difference-in-differences, -2.1%; 95% CI, -3.7 to -0.5).

CONCLUSIONS AND RELEVANCE

In this comparative effectiveness research study, compared with cancer programs with low use of neoadjuvant chemotherapy, those with high use had similar improvements in median overall survival and larger declines in short-term mortality.

A Systematic Review of Discrete Choice Experiments in Oncology Treatments

BACKGROUND

As the number and type of cancer treatments available rises and patients live with the consequences of their disease and treatments for longer, understanding preferences for cancer care can help inform decisions about optimal treatment development, access, and care provision. Discrete choice experiments (DCEs) are commonly used as a tool to elicit stakeholder preferences; however, their implementation in oncology may be challenging if burdensome trade-offs (e.g. length of life versus quality of life) are involved and/or target populations are small.

OBJECTIVES

The aim of this review was to characterise DCEs relating to cancer treatments that were conducted between 1990 and March 2020.

DATA SOURCES

EMBASE, MEDLINE, and the Cochrane Database of Systematic Reviews were searched for relevant studies.

STUDY ELIGIBILITY CRITERIA

Studies were included if they implemented a DCE and reported outcomes of interest (i.e. quantitative outputs on participants' preferences for cancer treatments), but were excluded if they were not focused on pharmacological, radiological or surgical treatments (e.g. cancer screening or counselling services), were non-English, or were a secondary analysis of an included study.

ANALYSIS METHODS

Analysis followed a narrative synthesis, and quantitative data were summarised using descriptive statistics, including rankings of attribute importance.

RESULT

Seventy-nine studies were included in the review. The number of published DCEs relating to oncology grew over the review period. Studies were conducted in a range of indications (n = 19), most commonly breast (n =10, 13%) and prostate (n = 9, 11%) cancer, and most studies elicited preferences of patients (n = 59, 75%). Across reviewed studies, survival attributes were commonly ranked as most important, with overall survival (OS) and progression-free survival (PFS) ranked most important in 58% and 28% of models, respectively. Preferences varied between stakeholder groups, with patients and clinicians placing greater importance on survival outcomes, and general population samples valuing health-related quality of life (HRQoL). Despite the emphasis of guidelines on the importance of using qualitative research to inform attribute selection and DCE designs, reporting on instrument development was mixed.

LIMITATIONS

No formal assessment of bias was conducted, with the scope of the paper instead providing a descriptive characterisation. The review only included DCEs relating to cancer treatments, and no insight is provided into other health technologies such as cancer screening. Only DCEs were included.

CONCLUSIONS AND IMPLICATIONS

Although there was variation in attribute importance between responder types, survival attributes were consistently ranked as important by both patients and clinicians. Observed challenges included the risk of attribute dominance for survival outcomes, limited sample sizes in some indications, and a lack of reporting about instrument development processes.

PROTOCOL REGISTRATION

PROSPERO 2020 CRD42020184232.

Neoadjuvant chemotherapy before surgery versus surgery followed by chemotherapy for initial treatment in advanced ovarian epithelial cancer

BACKGROUND

Epithelial ovarian cancer presents at an advanced stage in the majority of women. These women require a combination of surgery and chemotherapy for optimal treatment. Conventional treatment has been to perform surgery first and then give chemotherapy. However, there may be advantages to using chemotherapy before surgery.

OBJECTIVES

To assess whether there is an advantage to treating women with advanced epithelial ovarian cancer with chemotherapy before debulking surgery (neoadjuvant chemotherapy (NACT)) compared with conventional treatment where chemotherapy follows debulking surgery (primary debulking surgery (PDS)).

SEARCH METHODS

We searched the following databases up to 9 October 2020: the Cochrane Central Register of Controlled Trials (CENTRAL), Embase via Ovid, MEDLINE (Silver Platter/Ovid), PDQ and MetaRegister. We also checked the reference lists of relevant papers that were identified to search for further studies. The main investigators of relevant trials were contacted for further information.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of women with advanced epithelial ovarian cancer (Federation of International Gynaecologists and Obstetricians (FIGO) stage III/IV) who were randomly allocated to treatment groups that compared platinum-based chemotherapy before cytoreductive surgery with platinum-based chemotherapy following cytoreductive surgery.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias in each included trial. We extracted data of overall (OS) and progression-free survival (PFS), adverse events, surgically-related mortality and morbidity and quality of life outcomes.  We used GRADE methods to determine the certainty of evidence.

MAIN RESULTS

We identified 2227 titles and abstracts through our searches, of which five RCTs of varying quality and size met the inclusion criteria. These studies assessed a total of 1774 women with stage IIIc/IV ovarian cancer randomised to NACT followed by interval debulking surgery (IDS) or PDS followed by chemotherapy. We pooled results of the four studies where data were available and found little or no difference with regard to overall survival (OS) (Hazard Ratio (HR) 0.96, 95% CI 0.86 to 1.08; participants = 1692; studies = 4; high-certainty evidence) or progression-free survival in four trials where we were able to pool data (Hazard Ratio 0.98, 95% CI 0.88 to 1.08; participants = 1692; studies = 4; moderate-certainty evidence). Adverse events, surgical morbidity and quality of life (QoL) outcomes were variably and incompletely reported across studies. There are probably clinically meaningful differences in favour of NACT compared to PDS with regard to overall postoperative serious adverse effects (SAE grade 3+): 6% in NACT group, versus 29% in PDS group, (risk ratio (RR) 0.22, 95% CI 0.13 to 0.38; participants = 435; studies = 2; heterogeneity index (I2) = 0%; moderate-certainty evidence). NACT probably results in a large reduction in the need for stoma formation: 5.9% in NACT group, versus 20.4% in PDS group, (RR 0.29, 95% CI 0.12 to 0.74; participants = 632; studies = 2; I2 = 70%; moderate-certainty evidence), and probably reduces the risk of needing bowel resection at the time of surgery: 13.0% in NACT group versus 26.6% in PDS group (RR 0.49, 95% CI 0.30 to 0.79; participants = 1565; studies = 4; I2 = 79%; moderate-certainty evidence). NACT reduces postoperative mortality: 0.6% in NACT group, versus 3.6% in PDS group, (RR 0.16, 95% CI 0.06 to 0.46; participants = 1623; studies = 5; I2 = 0%; high-certainty evidence). QoL on the European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) scale produced inconsistent and imprecise results in three studies (MD -0.29, 95% CI -2.77 to 2.20; participants = 524; studies = 3; I2 = 81%; very low-certainty evidence) but the evidence is very uncertain and should be interpreted with caution.

AUTHORS' CONCLUSIONS

The available high to moderate-certainty evidence suggests there is little or no difference in primary survival outcomes between PDS and NACT. NACT probably reduces the risk of serious adverse events, especially those around the time of surgery, and reduces the risk of postoperative mortality and the need for stoma formation. These data will inform women and clinicians (involving specialist gynaecological multidisciplinary teams) and allow treatment to be tailored to the person, taking into account surgical resectability, age, histology, stage and performance status. Data from an unpublished study and ongoing studies are awaited.

Updates and New Options in Advanced Epithelial Ovarian Cancer Treatment

The medical and surgical treatment strategies for women with epithelial ovarian cancer continue to evolve. In the past several years, there has been significant progress backed by landmark clinical trials. Although primary epithelial ovarian cancer is still treated with a combination of surgery and systemic therapy, more complex surgical procedures and novel therapeutics have emerged as standard of care. Cytotoxic chemotherapy and maximal surgical effort remain mainstays, but targeted therapies are becoming more widespread and new data have called into question the role of surgery for women with recurrent disease. Poly ADP-ribose polymerase inhibitors have improved progression-free survival outcomes in both the frontline and recurrent settings, and their use has become increasingly widespread. The recent creation of treatment categories based on genetic changes reinforces the recommendation that all women with epithelial ovarian cancer have germline genetic testing, and new biomarker-driven drug approvals indicate that women may benefit from somatic molecular testing as well. To continue to identify novel strategies, however, enrollment on clinical trials remains of the utmost importance. With the evolving data on surgical approaches, targeted therapies such as antiangiogenics and poly ADP-ribose polymerase inhibitors, and the new therapeutic agents and combinations in development, we hope that advanced epithelial ovarian cancer will eventually transition from an almost universally fatal disease to one that can increasingly be cured.

Advanced ovarian cancer and cytoreductive surgery: Independent validation of a risk-calculator for perioperative adverse events

OBJECTIVE

To independently validate a published risk-calculator for adverse perioperative outcomes in patients with epithelial ovarian cancer undergoing debulking surgery at a high-volume surgical center.

METHODS

Using our institution's curated prospective ovarian cancer database, we identified patients with epithelial ovarian cancer who underwent a debulking procedure from 7/2015 to 5/2019, to be used as the validation cohort. Variables used in the published nomogram were collected. These included American Society of Anesthesiology classification, preoperative albumin, history of bleeding disorder, presence of ascites on preoperative imaging, designation of elective or emergent surgery, age of the patient, and a procedure score. Patients were included if they had information available for all the variables used in the nomogram, and 30-day follow-up within our institution. The primary outcome was Clavien-Dindo Class IV with specific conditions (postoperative sepsis, septic shock, cardiac arrest, myocardial infarction, pulmonary embolism, ventilation >48 h, or unplanned intubation) and 30-day mortality. The combination of these endpoints is called the combined complication rate.

RESULTS

A total of 700 patients who underwent debulking surgery for epithelial ovarian cancer during the timeframe met inclusion criteria. The combined complication rate was 11.7%; 9.9% of patients were readmitted; 2.7% required reoperation. Sepsis was the most common primary endpoint complication (4.4%), followed by septic shock (1.4%). There was no 30-day mortality in our cohort. The nomogram performed well, with a c index of 0.715 (95% CI 0.66-0.768), which was comparable to the published nomogram.

CONCLUSIONS

We independently validated a complication nomogram at a high-volume surgical center. This nomogram performs well at predicting a lower likelihood of serious postoperative complications. An enhanced nomogram would help identify patients at higher risk for serious complications.

Immunology and ovarian cancers

The current standard therapy of epithelial ovarian cancer (EOC) is the combination of surgery and multiagent chemotherapy with/without adding targeted therapy. After treatment, response rate is high and nearly all patients can achieve complete remission, even though they are advanced diseases; however, the majority of patients will relapse and subsequently die of diseases within several years after initial treatment. When treatment options are limited, there is the urgent need for new novel therapeutic approaches for precise cancer control. The development of chemoresistance and evading of the anticancer immune response may be one of the important causes contributing to the therapeutic failure, and therefore, it represents a paradigm shift in cancer research. An individual's immune response and interaction with EOC cells might be one of the key factors for cancer treatment. There are many interventions, including targeting certain type immunogenic EOC-associated antigens, immune checkpoint blockade, and adoptive cellular therapy, which present a profound opportunity to revolutionize EOC treatment. This review will encompass the interaction between EOC and immune system and highlight recent data regarding the research of immunotherapy in EOC.

Aberrant sialylation in ovarian cancers

Sialylation (the covalent addition of sialic acid to the terminal end of glycoproteins or glycans), tightly regulated cell- and microenvironment-specific process and orchestrated by sialyltransferases and sialidases (neuraminidases) family, is one of the posttranslational modifications, which plays an important biological role in the maintenance of normal physiology and involves many pathological dysfunctions. Glycans have roles in all the cancer hallmarks, referring to capabilities acquired during all steps of cancer development to initiate malignant transformation (a driver of a malignant genotype), enable cancer cells to survive, proliferate, and metastasize (a consequence of a malignant phenotype), which includes sustaining proliferative signaling, evading growth suppressor, resisting cell apoptosis, enabling replicative immortality, inducing angiogenesis, reprogramming of energy metabolism, evading tumor destruction, accumulating inflammatory microenvironment, and activating invasion and accelerating metastases. Regarding the important role of altered sialylation of cancers, further knowledge about the initiation and the consequences of altered sialylation pattern in tumor cells is needed, because all may offer a better chance for developing novel therapeutic strategy. In this review, we would like to update alteration of sialylation in ovarian cancers.

Patient preferences for maintenance PARP inhibitor therapy in ovarian cancer treatment

OBJECTIVE

To measure preferences of women with ovarian cancer regarding risks, side effects, costs and benefits afforded by maintenance therapy (MT) with a poly ADP ribose polymerase (PARP) inhibitor.

METHODS

A discrete-choice experiment elicited preferences of women with ovarian cancer regarding 6 attributes (levels in parentheses) relevant to decisions for MT versus treatment break: (1) overall survival (OS; 36, 38, 42 months); (2) progression-free survival (PFS; 15, 17, 21 months); (3) nausea (none, mild, moderate); (4) fatigue (none, mild, moderate); (5) probability of death from myelodysplastic syndrome/acute myelogenous leukemia (MDS/AML; 0% to 10%); (6) monthly out-of-pocket cost ($0 to $1000). Participants chose between 2 variable MT scenarios and a static scenario representing treatment break, with multiple iterations. Random-parameters logit regression was applied to model choices as a function of attribute levels.

RESULTS

95 eligible participants completed the survey; mean age was 62, 48% had recurrence, and 17% were ever-PARP inhibitor users. Participants valued OS (average importance weight 24.5 out of 100) and monthly costs (24.6) most highly, followed by risk of death from MDS/AML (17.9), nausea (14.7), PFS (10.5) and fatigue (7.8). Participants would accept 5% risk of MDS/AML if treatment provided 2.2 months additional OS or 4.8 months PFS. Participants would require gains of 2.6 months PFS to accept mild treatment-related fatigue and 4.4 months to accept mild nausea.

CONCLUSIONS

When considering MT, women with ovarian cancer are most motivated by gains in OS. Women expect at least 3-4 months of PFS benefit to bear mild side effects of treatment.