instruction:
Given a passage, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.
question:
Extranodal natural killer/T-cell lymphoma, nasal type (ENKTL), is an aggressive type of lymphoma whose standard treatment and validated prognostic model have not yet been defined.', 'CD30 expression was detected using immunohistochemistry in 96 ENKTL patients, and the data were used to evaluate its relationship with clinical features, treatment response and prognosis.', 'Expression of CD30 was detected in 31.2% of ENKTL patients, which was significantly correlated with B symptoms and elevated serum lactate dehydrogenase. The complete remission rate was not significantly different between CD30-positive and negative groups. After a median follow-up time of 31 months, 5-year overall survival (OS) and 5-year progression-free survival (PFS) rates in the CD30-positive group were both significantly lower than those in the CD30-negative group (34.1% vs. 64.4%, P=0.002, for 5 year-OS; 26.0% vs. 66.7%, P<0.001, for 5 year-PFS). In patients with an International Prognostic Index (IPI) or Korean Prognostic Index (KPI) score of 0-1, CD30 positivity was associated with shorter 5-year OS and PFS (IPI: P=0.001 and 0.002, respectively; KPI: P=0.018 and 0.023, respectively). In a multivariate Cox regression model, CD30 expression and stage were independent prognostic factors for OS (p=0.004 and p=0.012, respectively) and PFS (p=0.001 and p=0.022, respectively).
answer:
Is cD30 expression a novel prognostic indicator in extranodal natural killer/T-cell lymphoma , nasal type?


question:
The aim of this study was to review the impact of salvage external beam radiotherapy (EBRT) of postprostatectomy patients with long-term follow-up on biochemical-free recurrence (BFR) and metastatic-free survival, and to describe pathological and clinical predictors of outcome.', 'In the period 1987-2010, 76 postprostatectomy patients with biochemical and clinical recurrence received salvage EBRT. Patients were treated with conformal EBRT and 68 (90%) received a dose of 70 Gy; eight patients (10%) received a dose of 60-64 Gy. No patients received adjuvant or neoadjuvant androgen deprivation therapy in conjunction with salvage EBRT.', 'The median follow-up time after salvage EBRT was 82 months (range 5-192 months). Seventeen patients (22%) developed biochemical recurrence subsequent to postprostatectomy salvage EBRT during the observation time, and the overall 50 and 75 month actuarial BFR rates after salvage EBRT were 84% and 79%, respectively. Seven patients (9%) developed metastatic disease and two patients died of prostate cancer. Independent predictors of biochemical recurrence were seminal vesicle invasion (SVI) in the prostatectomy specimen (p < 0.05) and prostate-specific antigen doubling time (PSADT) of 6 months or less (p = 0.041) before salvage EBRT.
answer:
Is prostate-specific antigen doubling time subsequent to radical prostatectomy a predictor of outcome following salvage external beam radiation therapy : a single-centre experience?


question:
To study the association between self-reported sleep disturbances and dementia risk.', 'Self-reported sleep disturbances and established risk factors for dementia were measured in men at ages 50 (n\xa0=\xa01574) and 70 (n\xa0=\xa01029) years. Dementia incidence was determined by reviewing their patient history between ages 50 and 90 years. In addition, plasma levels of β-amyloid (Aβ) peptides 1-40 and 1-42 were measured at ages 70, 77, and 82 years.', "Cox regression demonstrated that men with self-reported sleep disturbances had a higher risk of developing dementia (+33%) and Alzheimer's disease (AD, +51%) than men without self-reported sleep disturbances (both P\xa0<\xa0.05). Binary logistic regression showed the increased risk for both dementia (+114%) and AD (+192%) were highest when sleep disturbance was reported at age 70 years (both P\xa0<\xa0.001). No group differences were found in Aβ levels.
answer:

Is self-reported sleep disturbance associated with Alzheimer 's disease risk in men?