***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    ***EXAMPLES*** 
    Input: Purpose To assess the clinical roles of [18F]fluorodeoxyglucose ( 18F-FDG ) positron emission tomography/computed tomography ( PET/CT ) performed 2 - 3 months after completion of concurrent chemoradiotherapy ( CCRT ) , along with pretherapy characteristics , in patients with advanced squamous cell carcinoma of the uterine cervix enrolled in a prospect i ve r and omized clinical trial . Methods Posttherapy PET/CT in patients with advanced FIGO stage or positive pelvic or para-aortic lymph node ( PALN ) defined on pretherapy PET/CT was classified as positive , equivocal , or negative . Overall survival ( OS ) rates between patients with different PET/CT results are compared . Pretherapy characteristics are examined for association with posttherapy PET/CT results and for prognostic significance in patients with equivocal or negative PET/CT . Results PET/CT scans ( n = 55 ) were positive , equivocal and negative in 9 , 13 and 33 patients , respectively . All patients with positive scans were confirmed to have residual or metastatic disease and died despite salvage therapies . There is a significant OS difference between patients with positive and equivocal scans ( P < .001 ) but not between patients with equivocal and negative scans ( P = .411 ) . Positive pretherapy PALN is associated with positive posttherapy PET/CT ( P = .033 ) and predicts a poorer survival in patients with equivocal or negative posttherapy PET/CT ( P < .001 ) . Conclusions Positive PET/CT 2 - 3 months posttherapy implies treatment failure and novel therapy is necessary to improve outcomes for such patients . A more intense posttherapy surveillance may be warranted in patients with positive pretherapy PALN Cervical cancer is the second most commonly diagnosed cancer and the third leading cause of cancer death among females in less developed countries . There were an estimated 527 600 new cervical cancer cases and 265 700 deaths worldwide in 2012 [ 1 ] . Nearly 90 % of cervical cancer deaths occurred in developing parts of the world . The large geographic variation in cervical cancer rates reflects differences in the availability of screening ( which allows for the detection and removal of precancerous lesions ) and in human papillomavirus ( HPV ) infection prevalence . However , cervical cancer still represents a major public health problem even in developed countries : more than 58 000 new cases of cervical cancer are diagnosed and 24 000 patients die in Europe every year [ 2 ] . Five-year relative survival for European women diagnosed with cervical cancer in 2000–2007 was 62 % , ranging from 57 % in Eastern Europe to 67 % in Northern Europe . Survival was particularly low ( < 55 % ) in Bulgaria , Latvia and Pol and and highest in Norway ( 71 % ) [ 3 ] . Survival decreased with advancing age at diagnosis , from 81 % for 15–44-year olds to 34 % for women 75 years . Survival increased significantly from 61 % in 1999–2001 to 65 % in 2005–2007 . FIGO stage is one of the most important prognostic factors . The most significant cause of cervical cancer is persistent papillomavirus infection . HPV is detected in 99 % of cervical tumours , particularly the oncogenic subtypes such as HPV 16 and 18 . To date , three HPV vaccines are licensed and available : the bivalent HPV virus-like particle vaccine ( 2vHPV ) , the quadrivalent HPV virus-like particle vaccine ( 4vHPV ) and nine-valent HPV virus-like particle vaccine ( 9vHPV ) . All 3 vaccines provide protection against HPV 16 and 18 . 4vHPV also includes HPV 6 and 11 which cause 90 % of genital warts . Furthermore , 9vHPV covers 5 more oncogenic HPV viruses ( HPV 31 , 33 , 45 , 52 and 58 ) in addition to the types already included in 4vHPV , which cause an additional 15 % of HPV-related cancers in women and 4 % of those in men [ 4 ] . Both the 2vHPV and 4vHPV have significant cross-protective activity against other oncogenic viruses . All three are efficacious against related infection and cervical , vaginal , vulvar and anal dysplasia [ 5–7 ] . Post-licensure reports from countries with established HPV vaccination programs indicate that HPV vaccination has a beneficial effect at the population level as early as 3 years after the introduction of an HPV vaccination programme , including decreases in the incidence of high- grade cervical abnormalities , the prevalence of vaccine HPV types and the incidence of genital warts [ 8 , 9 ] . Prophylactic administration of HPV vaccine can effectively prevent infection and disease associated with the vaccine HPV types . The effect of vaccination on the burden of cancer remains to be determined but , according to surrogate markers , it is expected to prevent > 70 % of cervical cancers . For many years , the Papanicolaou ( Pap ) test has been the st and ard method for cervical cancer screening , reducing the incidence by 60%–90 % and the death rate by 90 % . However , the limitations of this cytology-based test are the sensitivity ( 50 % ) and significant proportion of inadequate specimens . More recently , an HPV test has been introduced as a screening tool as HPV deoxyribonucleic acid ( DNA ) is present in almost all cervical cancers and it has demonstrated higher sensitivity for high grade cervical intraepithelial neoplasia ( CIN2þ ) than that achieved by cytology in several studies . A pooled analysis of four r and omised controlled trials of HPV-based cervical screening versus conventional cytology showed that HPV-based cervical screening provides 60%–70 % greater protection against Background Advanced stage cervical cancer is primarily treated by radiotherapy . Local tumor control is a prerequisite for cure . Imaging after treatment is controversial . Positron emission tomography ( PET ) combined with computer tomography ( PET-CT ) shows great promise for detecting metastases . On the other h and , magnetic resonance imaging ( MRI ) is superior in depicting anatomical details . The combination of PET-MRI could result in more accurate evaluation of cervical cancer treatment outcome . The aim of this pilot study is to share our initial experience with PET-MRI in the evaluation of treatment response in cervical cancer after radiation treatment . Methods Ten patients with cervical carcinoma ( FIGO ≥IB2 ) were prospect ively evaluated . Eleven weeks ( median ; range 8–15 weeks ) after radiation therapy , treatment response was evaluated by PET-MRI . The PET , MRI , and combined PET-MRI images were evaluated for the presence of local residual tumor and metastasis . Diagnostic performance was assessed by area under the receiver operator characteristic ( ROC ) curve for evaluation of local residual tumor . The readers were blinded for outcome data . Local residual disease , metastasis , diagnostic confidence , and change of opinion were scored on a 5-point Likert scale . The reference st and ard consisted of pathology and /or follow-up according to the clinical guidelines . Results Three out of ten patients had local residual abnormalities suggestive for tumor residue after radiation treatment . The availability of both PET and MRI result ed in an increase in diagnostic confidence in 80–90 % of all patients . Change of opinion was observed in 70 % and change of policy in 50 % , especially in the group with residual tumor . The diagnostic accuracy increased significantly for the radiologist if PET-MRI was combined ( AUC .54 versus .83 ) . Conclusions PET-MRI shows promise for evaluation of treatment response after radiation for cervical cancer , especially increasing diagnostic confidence , while potentially increasing diagnostic performance BACKGROUND Stage Ib and IIa cervical carcinoma can be cured by radical surgery or radiotherapy . These two procedures are equally effective , but differ in associated morbidity and type of complications . In this prospect i ve r and omised trial of radiotherapy versus surgery , our aim was to assess the 5-year survival and the rate and pattern of complications and recurrences associated with each treatment . METHODS Between September , 1986 , and December , 1991 , 469 women with newly diagnosed stage Ib and IIa cervical carcinoma were referred to our institute . 343 eligible patients were r and omised : 172 to surgery and 171 to radical radiotherapy . Adjuvant radiotherapy was delivered after surgery for women with surgical stage pT2b or greater , less than 3 mm of safe cervical stroma , cut-through , or positive nodes . The primary outcome measures were 5-year survival and the rate of complications . The analysis of survival and recurrence was by intention to treat and analysis of complications was by treatment delivered . FINDINGS 170 patients in the surgery group and 167 in the radiotherapy group were included in the intention-to-treat analysis ; scheduled treatment was delivered to 169 and 158 women , respectively , 62 of 114 women with cervical diameters of 4 cm or smaller and 46 of 55 with diameters larger than 4 cm received adjuvant therapy . After a median follow-up of 87 ( range 57 - 120 ) months , 5-year overall and disease-free survival were identical in the surgery and radiotherapy groups ( 83 % and 74 % , respectively , for both groups ) , 86 women developed recurrent disease : 42 ( 25 % ) in the surgery group and 44 ( 26 % ) in the radiotherapy group . Significant factors for survival in univariate and multivariate analyses were : cervical diameter , positive lymphangiography , and adeno-carcinomatous histotype . 48 ( 28 % ) surgery-group patients had severe morbidity compared with 19 ( 12 % ) radiotherapy-group patients ( p = 0.0004 ) . INTERPRETATION There is no treatment of choice for early-stage cervical carcinoma in terms of overall or disease-free survival . The combination of surgery and radiotherapy has the worst morbidity , especially urological complications . The optimum therapy for each patient should take account of clinical factors such as menopausal status , age , medical illness , histological type , and cervical diameter to yield the best cure with minimum complications Purpose To report 5-year outcomes of a prospect i ve registry study investigating posttherapy FDG PET/CT in women with locally advanced cervical cancer . A secondary analysis assessing the prognostic significance of HPV infection was performed . Methods Patients underwent definitive chemoradiation  followed by a single FDG PET/CT scan for response assessment . A complete metabolic response ( CMR ) was defined as no evidence of FDG-avid disease . Patients were dichotomized according to HPV infection status into a ‘ higher-risk ’ group and a ‘ lower-risk ’ group , with the higher-risk group comprising those with alpha-7 strain HPV ( subtypes 18 , 39 and 45 ) and those who were HPV-negative and the lower-risk group comprising those with alpha-9 strain HPV ( subtypes 16 , 31 , 33 , 52 and 58 ) and those with mixed strains . Survival outcomes , patterns of failure and salvage therapy outcomes were investigated for their association with metabolic response and HPV status . Results In 105 patients the median prospect i ve follow-up was 5.2 years . The 5-year cancer-specific , overall and progression-free survival rates in patients with a CMR were 97 % , 93 % and 86 % , respectively . In patients without a CMR , the corresponding 5-year survival rates were 36 % , 22 % and 0 % respectively ( p < 0.01 ) . PET response was associated with patterns of failure ( p < 0.01 ) , with the 5-year freedom from local , nodal and distant failure in patients with a CMR being 94 % , 90 % and 94 % , respectively . Of 16 patients who underwent salvage therapy , 12 had disease detected on the surveillance PET scan , and 8 achieved a post-salvage CMR of whom all were alive at a median of 4.9 years . DNA adequate for HPV analysis was extracted in 68 patients . The likelihood of a  PET metabolic response was not influenced by HPV infection status , with 71 % and 75 % of higher-risk and lower-risk patients , respectively , achieving CMR ( p = 0.83 ) . Higher-risk patients had a poorer OS ( HR 2.6 , range 1.0 – 6.6 , p = 0.05 ) in univariable analysis but not multivariable analysis ( p = 0.11 ) . Conclusion At 5 years CMR remains a powerful factor predicting survival after initial and salvage therapy . Metabolic response was not associated with HPV infection risk . Further studies are required to establish the association with HPV infection risk and survival after chemoradiation CONTEXT Retrospective studies have demonstrated that the use of positron emission tomography ( PET ) with F-18 fluorodeoxyglucose ( FDG ) in the posttherapy evaluation of patients with cervical carcinoma is predictive of survival outcome . OBJECTIVE To vali date the association between the metabolic response on the 3-month posttherapy FDG-PET and long- 
    Output:
    
Response results of post-RT ¹⁸F-FDG PET were significant prognostic factors in patients with uterine cervical cancer , and ¹⁸F-FDG PET could be a reasonable follow-up imaging modality