Summary Background The international standard of care for women with suspected advanced ovarian cancer is surgical debulking followed by platinum-based chemotherapy. We aimed to establish whether use ...of platinum-based primary chemotherapy followed by delayed surgery was an effective and safe alternative treatment regimen. Methods In this phase 3, non-inferiority, randomised, controlled trial (CHORUS) undertaken in 87 hospitals in the UK and New Zealand, we enrolled women with suspected stage III or IV ovarian cancer. We randomly assigned women (1:1) either to undergo primary surgery followed by six cycles of chemotherapy, or to three cycles of primary chemotherapy, then surgery, followed by three more cycles of completion chemotherapy. Each 3-week cycle consisted of carboplatin AUC5 or AUC6 plus paclitaxel 175 mg/m2 , or an alternative carboplatin combination regimen, or carboplatin monotherapy. We did the random assignment by use of a minimisation method with a random element, and stratified participants according to the randomising centre, largest radiological tumour size, clinical stage, and prespecified chemotherapy regimen. Patients and investigators were not masked to group assignment. The primary outcome measure was overall survival. Primary analyses were done in the intention-to-treat population. To establish non-inferiority, the upper bound of a one-sided 90% CI for the hazard ratio (HR) had to be less than 1·18. This trial is registered, number ISRCTN74802813, and is closed to new participants. Findings Between March 1, 2004, and Aug 30, 2010, we randomly assigned 552 women to treatment. Of the 550 women who were eligible, 276 were assigned to primary surgery and 274 to primary chemotherapy. All were included in the intention-to-treat analysis; 251 assigned to primary surgery and 253 to primary chemotherapy were included in the per-protocol analysis. As of May 31, 2014, 451 deaths had occurred: 231 in the primary-surgery group versus 220 in the primary-chemotherapy group. Median overall survival was 22·6 months in the primary-surgery group versus 24·1 months in primary chemotherapy. The HR for death was 0·87 in favour of primary chemotherapy, with the upper bound of the one-sided 90% CI 0·98 (95% CI 0·72–1·05). Grade 3 or 4 postoperative adverse events and deaths within 28 days after surgery were more common in the primary-surgery group than in the primary-chemotherapy group (60 24% of 252 women vs 30 14% of 209, p=0·0007, and 14 women 6% vs 1 woman <1%, p=0·001). The most common grade 3 or 4 postoperative adverse event was haemorrhage in both groups (8 women 3% in the primary-surgery group vs 14 6% in the primary-chemotherapy group). 110 (49%) of 225 women receiving primary surgery and 102 (40%) of 253 receiving primary chemotherapy had a grade 3 or 4 chemotherapy related toxic effect (p=0·0654), mostly uncomplicated neutropenia (20% and 16%, respectively). One fatal toxic effect, neutropenic sepsis, occurred in the primary-chemotherapy group. Interpretation In women with stage III or IV ovarian cancer, survival with primary chemotherapy is non-inferior to primary surgery. In this study population, giving primary chemotherapy before surgery is an acceptable standard of care for women with advanced ovarian cancer. Funding Cancer Research UK and the Royal College of Obstetricians and Gynaecologists.
Summary Background Cervical intraepithelial neoplasia grade 2 or greater (CIN2+) is the surrogate endpoint used in licensure trials of human papillomavirus (HPV) vaccines. Vaccine efficacy against ...CIN3+, the immediate precursor to invasive cervical cancer, is more difficult to measure because of its lower incidence, but provides the most stringent evidence of potential cancer prevention. We report vaccine efficacy against CIN3+ and adenocarcinoma in situ (AIS) in the end-of-study analysis of PATRICIA (PApilloma TRIal against Cancer In young Adults). Methods Healthy women aged 15–25 years with no more than six lifetime sexual partners were included in PATRICIA, irrespective of their baseline HPV DNA status, HPV-16 or HPV-18 serostatus, or cytology. Women were randomly assigned (1:1) to receive an HPV-16/18 AS04-adjuvanted vaccine or a control hepatitis A vaccine via an internet-based central randomisation system using a minimisation algorithm to account for age ranges and study sites. The patients and study investigators were masked to allocated vaccine. The primary endpoint of PATRICIA has been reported previously. In the present end-of-study analysis, we focus on CIN3+ and AIS in the populations of most clinical interest, the total vaccinated cohort (TVC) and the TVC-naive. The TVC comprised all women who received at least one vaccine dose, approximating catch-up populations and including sexually active women (vaccine n=9319; control=9325). The TVC-naive comprised women with no evidence of oncogenic HPV infection at baseline, approximating early adolescent HPV exposure (vaccine n=5824; control=5820). This study is registered with ClinicalTrials.gov , number NCT00122681. Findings Vaccine efficacy against CIN3+ associated with HPV-16/18 was 100% (95% CI 85·5–100) in the TVC-naive and 45·7% (22·9–62·2) in the TVC. Vaccine efficacy against all CIN3+ (irrespective of HPV type in the lesion and including lesions with no HPV DNA detected) was 93·2% (78·9–98·7) in the TVC-naive and 45·6% (28·8–58·7) in the TVC. In the TVC-naive, vaccine efficacy against all CIN3+ was higher than 90% in all age groups. In the TVC, vaccine efficacy against all CIN3+ and CIN3+ associated with HPV-16/18 was highest in the 15–17 year age group and progressively decreased in the 18–20 year and 21–25 year age groups. Vaccine efficacy against all AIS was 100% (31·0–100) and 76·9% (16·0–95·8) in the TVC-naive and TVC, respectively. Serious adverse events occurred in 835 (9·0%) and 829 (8·9%) women in the vaccine and control groups, respectively; only ten events (0·1%) and five events (0·1%), respectively, were considered to be related to vaccination. Interpretation PATRICIA end-of-study results show excellent vaccine efficacy against CIN3+ and AIS irrespective of HPV DNA in the lesion. Population-based vaccination that incorporates the HPV-16/18 vaccine and high coverage of early adolescents might have the potential to substantially reduce the incidence of cervical cancer. Funding GlaxoSmithKline Biologicals.
Summary Background In four randomised trials, human papillomavirus (HPV)-based screening for cervical cancer was compared with cytology-based cervical screening, and precursors of cancer were the ...endpoint in every trial. However, direct estimates are missing of the relative efficacy of HPV-based versus cytology-based screening for prevention of invasive cancer in women who undergo regular screening, of modifiers (eg, age) of this relative efficacy, and of the duration of protection. We did a follow-up study of the four randomised trials to investigate these outcomes. Methods 176 464 women aged 20–64 years were randomly assigned to HPV-based (experimental arm) or cytology-based (control arm) screening in Sweden (Swedescreen), the Netherlands (POBASCAM), England (ARTISTIC), and Italy (NTCC). We followed up these women for a median of 6·5 years (1 214 415 person-years) and identified 107 invasive cervical carcinomas by linkage with screening, pathology, and cancer registries, by masked review of histological specimens, or from reports. Cumulative and study-adjusted rate ratios (experimental vs control) were calculated for incidence of invasive cervical carcinoma. Findings The rate ratio for invasive cervical carcinoma among all women from recruitment to end of follow-up was 0·60 (95% CI 0·40–0·89), with no heterogeneity between studies (p=0·52). Detection of invasive cervical carcinoma was similar between screening methods during the first 2·5 years of follow-up (0·79, 0·46–1·36) but was significantly lower in the experimental arm thereafter (0·45, 0·25–0·81). In women with a negative screening test at entry, the rate ratio was 0·30 (0·15–0·60). The cumulative incidence of invasive cervical carcinoma in women with negative entry tests was 4·6 per 105 (1·1–12·1) and 8·7 per 105 (3·3–18·6) at 3·5 and 5·5 years, respectively, in the experimental arm, and 15·4 per 105 (7·9–27·0) and 36·0 per 105 (23·2–53·5), respectively, in the control arm. Rate ratios did not differ by cancer stage, but were lower for adenocarcinoma (0·31, 0·14–0·69) than for squamous-cell carcinoma (0·78, 0·49–1·25). The rate ratio was lowest in women aged 30–34 years (0·36, 0·14–0·94). Interpretation HPV-based screening provides 60–70% greater protection against invasive cervical carcinomas compared with cytology. Data of large-scale randomised trials support initiation of HPV-based screening from age 30 years and extension of screening intervals to at least 5 years. Funding European Union, Belgian Foundation Against Cancer, KCE-Centre d'Expertise, IARC, The Netherlands Organisation for Health Research and Development, the Italian Ministry of Health.
Summary Background We evaluated the efficacy of the human papillomavirus HPV-16/18 AS04-adjuvanted vaccine against non-vaccine oncogenic HPV types in the end-of-study analysis after 4 years of ...follow-up in PATRICIA (PApilloma TRIal against Cancer In young Adults). Methods Healthy women aged 15–25 years with no more than six lifetime sexual partners were included in PATRICIA irrespective of their baseline HPV DNA status, HPV-16 or HPV-18 serostatus, or cytology. Women were randomly assigned (1:1) to HPV-16/18 vaccine or a control hepatitis A vaccine, via an internet-based central randomisation system using a minimisation algorithm to account for age ranges and study sites. The study was double-blind. The primary endpoint of PATRICIA has been reported previously; the present analysis evaluates cross-protective vaccine efficacy against non-vaccine oncogenic HPV types in the end-of-study analysis. Analyses were done for three cohorts: the according-to-protocol cohort for efficacy (ATP-E; vaccine n=8067, control n=8047), total vaccinated HPV-naive cohort (TVC-naive; no evidence of infection with 14 oncogenic HPV types at baseline, approximating young adolescents before sexual debut; vaccine n=5824, control n=5820), and the total vaccinated cohort (TVC; all women who received at least one vaccine dose, approximating catch-up populations that include sexually active women; vaccine n=9319, control=9325). Vaccine efficacy was evaluated against 6-month persistent infection, cervical intraepithelial neoplasia grade 2 or greater (CIN2+) associated with 12 non-vaccine HPV types (individually or as composite endpoints), and CIN3+ associated with the composite of 12 non-vaccine HPV types. This study is registered with ClinicalTrials.gov , number NCT00122681. Findings Consistent vaccine efficacy against persistent infection and CIN2+ (with or without HPV-16/18 co-infection) was seen across cohorts for HPV-33, HPV-31, HPV-45, and HPV-51. In the most conservative analysis of vaccine efficacy against CIN2+, where all cases co-infected with HPV-16/18 were removed, vaccine efficacy was noted for HPV-33 in all cohorts, and for HPV-31 in the ATP-E and TVC-naive. Vaccine efficacy against CIN2+ associated with the composite of 12 non-vaccine HPV types (31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, and 68), with or without HPV-16/18 co-infection, was 46·8% (95% CI 30·7–59·4) in the ATP-E, 56·2% (37·2–69·9) in the TVC-naive, and 34·2% (20·4–45·8) in the TVC. Corresponding values for CIN3+ were 73·8% (48·3–87·9), 91·4% (65·0–99·0), and 47·5% (22·8–64·8). Interpretation Data from the end-of-study analysis of PATRICIA show cross-protective efficacy of the HPV-16/18 vaccine against four oncogenic non-vaccine HPV types—HPV-33, HPV-31, HPV-45, and HPV-51—in different trial cohorts representing diverse groups of women. Funding GlaxoSmithKline Biologicals.
Summary Background Although the risk of human papillomavirus (HPV) infection is greatest in young women, women older than 25 years remain at risk. We present data from the VIVIANE study of the HPV ...16/18 AS04-adjuvanted vaccine in adult women after 7 years of follow-up. Methods In this phase 3, double-blind, randomised controlled trial, healthy women older than 25 years were enrolled (age stratified: 26–35 years, 36–45 years, and ≥46 years). Up to 15% in each age stratum had a history of HPV infection or disease. Women were randomly assigned (1:1) to receive HPV 16/18 vaccine or aluminium hydroxide control, with an internet-based system. The primary endpoint was vaccine efficacy against 6-month persistent infection or cervical intraepithelial neoplasia grade 1 or greater (CIN1+) associated with HPV 16/18. We did analyses in the according-to-protocol cohort for efficacy and total vaccinated cohort. Data for the combined primary endpoint in the according-to-protocol cohort for efficacy were considered significant when the lower limit of the 96·2% CI around the point estimate was greater than 30%. For all other endpoints and cohorts, data were considered significant when the lower limit of the 96·2% CI was greater than 0%. This study is registered with ClinicalTrials.gov , number NCT00294047. Findings The first participant was enrolled on Feb 16, 2006, and the last study visit took place on Jan 29, 2014. 4407 women were in the according-to-protocol cohort for efficacy (n=2209 vaccine, n=2198 control) and 5747 women in the total vaccinated cohort (n=2877 vaccine, n=2870 control). At month 84, in women seronegative for the corresponding HPV type in the according-to-protocol cohort for efficacy, vaccine efficacy against 6-month persistent infection or CIN1+ associated with HPV 16/18 was significant in all age groups combined (90·5%, 96·2% CI 78·6–96·5). Vaccine efficacy against HPV 16/18-related cytological abnormalities (atypical squamous cells of undetermined significance and low-grade squamous intraepithelial lesion) and CIN1+ was also significant. We also noted significant cross-protective efficacy against 6-month persistent infection with HPV 31 (65·8%, 96·2% CI 24·9–85·8) and HPV 45 (70·7%, 96·2% CI 34·2–88·4). In the total vaccinated cohort, vaccine efficacy against CIN1+ irrespective of HPV was significant (22·9%, 96·2% CI 4·8–37·7). Serious adverse events related to vaccination occurred in five (0·2%) of 2877 women in the vaccine group and eight (0·3%) of 2870 women in the control group. Interpretation In women older than 25 years, the HPV 16/18 vaccine continues to protect against infections, cytological abnormalities, and lesions associated with HPV 16/18 and CIN1+ irrespective of HPV type, and infection with non-vaccine types HPV 31 and HPV 45 over 7 years of follow-up. Funding GlaxoSmithKline Biologicals SA.
Summary Background Although adolescent girls are the main population for prophylactic human papillomavirus (HPV) vaccines, adult women who remain at risk of cervical cancer can also be vaccinated. We ...report data from the interim analysis of the ongoing VIVIANE study, the aim of which is to assess the efficacy, safety, and immunogenicity of the HPV 16/18 AS04-adjuvanted vaccine in adult women. Methods In this phase 3, multinational, double-blind, randomised controlled trial, we randomly assigned healthy women older than 25 years to the HPV 16/18 vaccine or control (1:1), via an internet-based system with an algorithm process that accounted for region, age stratum, baseline HPV DNA status, HPV 16/18 serostatus, and cytology. Enrolment was age-stratified, with about 45% of participants in each of the 26–35 and 36–45 years age strata and 10% in the 46 years and older stratum. Up to 15% of women in each age stratum could have a history of HPV infection or disease. The primary endpoint was vaccine efficacy against 6-month persistent infection or cervical intraepithelial neoplasia grade 1 or higher (CIN1+) associated with HPV 16/18. The primary analysis was done in the according-to-protocol cohort for efficacy, which consists of women who received all three vaccine or control doses, had negative or low-grade cytology at baseline, and had no history of HPV disease. Secondary analyses included vaccine efficacy against non-vaccine oncogenic HPV types. Mean follow-up time was 40·3 months. This study is registered with ClinicalTrials.gov , number NCT00294047. Findings The first participant was enrolled on Feb 16, 2006, and the last study visit for the present analysis took place on Dec 10, 2010; 5752 women were included in the total vaccinated cohort (n=2881 vaccine, n=2871 control), and 4505 in the according-to-protocol cohort for efficacy (n=2264 vaccine, n=2241 control). Vaccine efficacy against HPV 16/18-related 6-month persistent infection or CIN1+ was significant in all age groups combined (81·1%, 97·7% CI 52·1–94·0), in the 26–35 years age group (83·5%, 45·0–96·8), and in the 36–45 years age group (77·2%, 2·8–96·9); no cases were seen in women aged 46 years and older. Vaccine efficacy against atypical squamous cells of undetermined significance or greater associated with HPV 16/18 was also significant. We also noted significant cross-protective vaccine efficacy against 6-month persistent infection with HPV 31 (79·1%, 97·7% CI 27·6–95·9) and HPV 45 (76·9%, 18·5–95·6) Serious adverse events occurred in 285 (10%) of 2881 women in the vaccine group and 267 (9%) of 2871 in the control group; five (<1%) and eight (<1%) of these events, respectively, were believed to be related to vaccination. Interpretation In women older than 25 years, the HPV 16/18 vaccine is efficacious against infections and cervical abnormalities associated with the vaccine types, as well as infections with the non-vaccine HPV types 31 and 45. Funding GlaxoSmithKline Biologicals SA.
Ovarian cancer Jayson, Gordon C, Prof; Kohn, Elise C, MD; Kitchener, Henry C, Prof ...
The Lancet (British edition),
10/2014, Letnik:
384, Številka:
9951
Journal Article
Recenzirano
Summary Epithelial ovarian cancer is the commonest cause of gynaecological cancer-associated death. The disease typically presents in postmenopausal women, with a few months of abdominal pain and ...distension. Most women have advanced disease (International Federation of Gynecology and Obstetrics FIGO stage III), for which the standard of care remains surgery and platinum-based cytotoxic chemotherapy. Although this treatment can be curative for most patients with early stage disease, most women with advanced disease will develop many episodes of recurrent disease with progressively shorter disease-free intervals. These episodes culminate in chemoresistance and ultimately bowel obstruction, the most frequent cause of death. For women whose disease continues to respond to platinum-based drugs, the disease can often be controlled for 5 years or more. Targeted treatments such as antiangiogenic drugs or poly (ADP-ribose) polymerase inhibitors offer potential for improved survival. The efficacy of screening, designed to detect the disease at an earlier and curable stage remains unproven, with key results expected in 2015.
Human papillomavirus and cervical cancer Crosbie, Emma J, PhD; Einstein, Mark H, MD; Franceschi, Silvia, MD ...
The Lancet (British edition),
09/2013, Letnik:
382, Številka:
9895
Journal Article
Recenzirano
Summary Cervical cancer is caused by human papillomavirus infection. Most human papillomavirus infection is harmless and clears spontaneously but persistent infection with high-risk human ...papillomavirus (especially type 16) can cause cancer of the cervix, vulva, vagina, anus, penis, and oropharynx. The virus exclusively infects epithelium and produces new viral particles only in fully mature epithelial cells. Human papillomavirus disrupts normal cell-cycle control, promoting uncontrolled cell division and the accumulation of genetic damage. Two effective prophylactic vaccines composed of human papillomavirus type 16 and 18, and human papillomavirus type 16, 18, 6, and 11 virus-like particles have been introduced in many developed countries as a primary prevention strategy. Human papillomavirus testing is clinically valuable for secondary prevention in triaging low-grade cytology and as a test of cure after treatment. More sensitive than cytology, primary screening by human papillomavirus testing could enable screening intervals to be extended. If these prevention strategies can be implemented in developing countries, many thousands of lives could be saved.
Summary Background About 15% of patients with endometrial cancer have high-risk features and are at increased risk of distant metastases and endometrial cancer-related death. We designed the PORTEC-3 ...trial to investigate the benefit of adjuvant chemoradiotherapy compared with radiotherapy alone for women with high-risk endometrial cancer. Methods PORTEC-3 was a multicentre, open-label, randomised, international trial. Women with high-risk endometrial cancer were randomly allocated (1:1) to radiotherapy alone (48·6 Gy) in 1·8 Gy fractions five times a week or chemoradiotherapy (two cycles concurrent cisplatin 50 mg/m2 and four adjuvant cycles of carboplatin area under the curve AUC 5 and paclitaxel 175 mg/m2 ) using a biased coin minimisation procedure with stratification for participating centre, lymphadenectomy, stage of cancer, and histological type. The primary endpoints of the PORTEC-3 trial were overall survival and failure-free survival analysed in the intention-to-treat population. This analysis focuses on 2-year toxicity and health-related quality of life as secondary endpoints; analysis was done according to treatment received. Health-related quality of life was assessed with the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30) the cervix cancer module and chemotherapy and neuropathy subscales of the ovarian cancer module at baseline, after radiotherapy and at 6, 12, 24, 36, and 60 months after randomisation. Adverse events were graded with Common Terminology Criteria for Adverse Events version 3.0. The study was closed on Dec 20, 2013, after achieving complete accrual, and follow-up remains ongoing for the primary outcomes analysis. This trial is registered with ISRCTN.com , number ISRCTN14387080, and with ClinicalTrials.gov , number NCT00411138. Findings Between Sept 15, 2006, and Dec 20, 2013, 686 women were randomly allocated in the PORTEC-3 trial. Of these, 660 met eligibility criteria, and 570 (86%) were evaluable for health-related quality of life. Median follow-up was 42·3 months (IQR 25·8–55·1). At completion of radiotherapy and at 6 months, EORTC QLQ-C30 functioning scales were significantly lower (worse functioning) and health-related quality of life symptom scores higher (worse symptoms) for the chemoradiotherapy group compared with radiotherapy alone, improving with time. At 12 and 24 months, global health or quality of life was similar between groups, whereas physical functioning scores remained slightly lower in patients who received chemoradiotherapy compared with patients who received radiotherapy alone. At 24 months, 48 (25%) of 194 patients in the chemoradiotherapy group reported severe tingling or numbness compared with 11 (6%) of 170 patients in the radiotherapy alone group (p<0·0001). Grade 2 or worse adverse events were found during treatment in 309 (94%) of 327 patients in the chemoradiotherapy group versus 145 (44%) of 326 patients in the radiotherapy alone group, and grade 3 or worse events were found in 198 (61%) of 327 patients in the chemoradiotherapy group versus 42 (13%) of 326 patients in the radiotherapy alone group (p<0·0001), with most of the grade 3 adverse events being haematological (45%). At 12 and 24 months, no significant differences in grade 3 or worse adverse events were found between groups; only grade 2 or higher sensory neuropathy adverse events persisted at 24 months (25 10% of 240 patients in the chemoradiotherapy group vs one <1% of 247 patients in the radiotherapy alone group; p<0·0001). Interpretation Despite the increased physician and patient-reported toxicities, this schedule of adjuvant chemotherapy given during and after radiotherapy in patients with high-risk endometrial cancer is feasible, with rapid recovery after treatment, but with persistence of patient-reported sensory neurological symptoms in 25% of patients. We await the analysis of primary endpoints before final conclusions are made. Funding Dutch Cancer Society, Cancer Research UK, National Health and Medical Research Council, Project Grant, Cancer Australia Grant, Italian Medicines Agency, and Canadian Cancer Society Research Institute.
Summary Background The aim of this interim analysis of a large, international phase III study was to assess the efficacy of an AS04 adjuvanted L1 virus-like-particle prophylactic candidate vaccine ...against infection with human papillomavirus (HPV) types 16 and 18 in young women. Methods 18 644 women aged 15–25 years were randomly assigned to receive either HPV16/18 vaccine (n=9319) or hepatitis A vaccine (n=9325) at 0, 1, and 6 months. Of these women, 88 were excluded because of high-grade cytology and 31 for missing cytology results. Thus, 9258 women received the HPV16/18 vaccine and 9267 received the control vaccine in the total vaccinated cohort for efficacy, which included women who had prevalent oncogenic HPV infections, often with several HPV types, as well as low-grade cytological abnormalities at study entry and who received at least one vaccine dose. We assessed cervical cytology and subsequent biopsy for 14 oncogenic HPV types by PCR. The primary endpoint—vaccine efficacy against cervical intraepithelial neoplasia (CIN) 2+ associated with HPV16 or HPV18—was assessed in women who were seronegative and DNA negative for the corresponding vaccine type at baseline (month 0) and allowed inclusion of lesions with several oncogenic HPV types. This interim event-defined analysis was triggered when at least 23 cases of CIN2+ with HPV16 or HPV18 DNA in the lesion were detected in the total vaccinated cohort for efficacy. Analyses were done on a modified intention-to-treat basis. This trial is registered with the US National Institutes of Health clinical trial registry, number NCT00122681. Findings Mean length of follow-up for women in the primary analysis for efficacy at the time of the interim analysis was 14·8 (SD 4·9) months. Two cases of CIN2+ associated with HPV16 or HPV18 DNA were seen in the HPV16/18 vaccine group; 21 were recorded in the control group. Of the 23 cases, 14 (two in the HPV16/18 vaccine group, 12 in the control group) contained several oncogenic HPV types. Vaccine efficacy against CIN2+ containing HPV16/18 DNA was 90·4% (97·9% CI 53·4–99·3; p<0·0001). No clinically meaningful differences were noted in safety outcomes between the study groups. Interpretation The adjuvanted HPV16/18 vaccine showed prophylactic efficacy against CIN2+ associated with HPV16 or HPV18 and thus could be used for cervical cancer prevention.
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