A machine learning approach for differentiating malignant from benign enhancing foci on breast MRI.

BACKGROUND: Differentiate malignant from benign enhancing foci on breast magnetic resonance imaging (MRI) through radiomic signature. METHODS: Forty-five enhancing foci in 45 patients were included in this retrospective study, with needle biopsy or imaging follow-up serving as a reference standard. There were 12 malignant and 33 benign lesions. Eight benign lesions confirmed by over 5-year negative follow-up and 15 malignant histopathologically confirmed lesions were added to the dataset to provide reference cases to the machine learning analysis. All MRI examinations were performed with a 1.5-T scanner. One three-dimensional T1-weighted unenhanced sequence was acquired, followed by four dynamic sequences after intravenous injection of 0.1 mmol/kg of gadobenate dimeglumine. Enhancing foci were segmented by an expert breast radiologist, over 200 radiomic features were extracted, and an evolutionary machine learning method ("training with input selection and testing") was applied. For each classifier, sensitivity, specificity and accuracy were calculated as point estimates and 95% confidence intervals (CIs). RESULTS: A k-nearest neighbour classifier based on 35 selected features was identified as the best performing machine learning approach. Considering both the 45 enhancing foci and the 23 additional cases, this classifier showed a sensitivity of 27/27 (100%, 95% CI 87-100%), a specificity of 37/41 (90%, 95% CI 77-97%), and an accuracy of 64/68 (94%, 95% CI 86-98%). CONCLUSION: This preliminary study showed the feasibility of a radiomic approach for the characterisation of enhancing foci on breast MRI.

Prognostic Value of the Diverticular Disease Severity Score Based on CT Colonography: Follow-up in Patients Recovering from Acute Diverticulitis.

RATIONALE AND OBJECTIVES: To assess the prognostic value of a diverticular disease severity score (DDSS) based on computed tomography colonography (CTC) after acute diverticulitis (AD). MATERIALS AND METHODS: Of 252 patients who had an AD episode, we finally selected 46 patients who underwent both conventional CT at the acute event and CTC after 9 ± 7 weeks. Of these 46 patients, 17 underwent elective surgery after CTC. Disease severity was assessed with a 0-4 modified Hinchey CT-based score and a 1-4 CTC-based DDSS. A phone survey was performed 27 months later (range 4-52) for the 29 patients not surgically treated. RESULTS: Significant correlation was found between CTC-based DDSS and clinical follow-up (P = 0.022) or elective surgery (P = 0.007), but not between clinical follow-up and CT-based score, extraluminal gas, C-reactive protein serum level, age, gender, or first versus recurrent AD episode. CTC demonstrated relevant additional findings in five of 46 (11%) patients: two AD complications (enterocolic and enterotubal fistulae), two colon cancers, and one extracolonic (lung) cancer. CONCLUSIONS: The CTC-based DDSS showed a prognostic value and correlated with the risk of undergoing surgery, and clinically relevant additional findings were found in more than 10% of patients. CTC could be the preferred test in patients recovering after AD.

Contrast enhanced chest-MDCT in oncologic patients. Prospective evaluation of the prevalence of incidental pulmonary embolism and added value of thin reconstructions.

OBJECTIVES: To prospectively assess prevalence/characteristics of clinically unsuspected pulmonary embolism (PE) in cancer patients undergoing follow-up chest MDCT and investigate MDCT protocol. METHODS: We evaluated 1013 oncologic patients. MDCT images at 5 and 1.25 mm thickness were independently evaluated. Pulmonary artery opacification degree was assessed. Presence, level, and site of PE were reported. Type of malignancy and metastases were reported for PE-positive patients. RESULTS: After excluding 1.4% (14/1013) of examinations due to inadequate vessel opacification, 999 patients (572 male; mean age:68 ± 12 years; range:26-93 years) entered the study. Prevalence of PE was 5%. There was significant improvement in the sensitivity for both readers in the evaluation of 1.25 mm compared to 5 mm images (46-50% to 82-92%). 30% (15/51) PE were not described by the radiologist in the prospectively issued report; 53 % (27/51) of PE were segmental, 72.5% (37/51) unilateral. The right lower lobe was the most involved (59%). 27% patients had colon cancer, 18% lung cancer. Among PE-positive patients (25 male; mean age 70 ± 10 years; range:44-87 years), 25% (13/51) had lung cancer, 15% (8/51) colon cancer. CONCLUSIONS: Thin reconstructions are essential for PE diagnosis, regardless of reader experience. Regarding oncologic patients, incidental PE diagnosis influences anticoagulation therapy. KEY POINTS: • CT pulmonary angiography is the gold standard for PE diagnosis. • Cancer and oncological treatments are risk factors for PE. • The prevalence of unsuspected PE was 5%. • Thin reconstructions are essential for PE diagnosis regardless of reader experience. • In oncologic patients, PE diagnosis influences anticoagulation therapy.

Age and fertility: can women wait until their early thirties to try for a first birth?

Postponing the start of childbearing raises the question of fertility postponed versus fertility foregone. One of the limitations of previous studies of 'How late can you wait?' is that any observed decline in the probability of conception with age could be due to a decline in fecundability with age or due to a decline in coital frequency with age or due to both factors. Using data from a multinational longitudinal study conducted to determine the daily probability of conception among healthy subjects, a discrete-time event history model with long-term survivors (sterile population) is used to study the relationship between age and fecundability for childless women, while controlling for the pattern of intercourse within a menstrual cycle. The findings suggest that women can wait until their early thirties to try for a first birth, providing that they are not already sterile, as the magnitude of the decline in fecundability is very modest and of little practical importance.

Cervical mucus symptom and daily fecundability: first results from a new database.

With the collaboration of Italian centres providing services on natural family planning, a prospective study collected data on 2755 menstrual cycles of 193 women. A database was constructed using information on the daily characteristics of cervical mucus and episodes of intercourse. Taking the day of peak mucus as a conventional marker of ovulation, the database identified the length (12 days) and location of a 'window' of potential fertility, the highest level of conception probability being confined to the central five to six days. Univariate analysis provided evidence of the impact on fecundability of the woman's age and the basic infertile pattern of a cycle. Several analytical approaches highlighted the relationship between daily mucus characteristics and levels of fecundability

Cervical mucus secretions on the day of intercourse: an accurate marker of highly fertile days.

OBJECTIVE: To provide estimates of the probabilities of conception according to vulvar mucus observations classified by the woman on the day of intercourse. STUDY DESIGN: Prospective cohort study of 193 outwardly healthy Italian women using the Billings Ovulation Method. Outcome measures include 161 conception cycles and 2594 non-conception cycles with daily records of the type of mucus and the occurrences of sexual intercourse. RESULTS: The probability of conception ranged from 0.003 for days with no noticeable secretions to 0.29 for days with most fertile-type mucus detected by the woman. The probability of most fertile type mucus by day of the menstrual cycle increased from values <20% outside of days 10-17 to a peak of 59% on day 13. CONCLUSION: Regardless of the timing of intercourse in the menstrual cycle, the probability of conception is essentially 0 on days with no secretions. This probability increases dramatically to near 30% on days with most fertile-type mucus, an association that accurately predicts both the timing of the fertile interval and the day-specific conception probabilities across the menstrual cycle.

Reduced fertilization rates in older men when cervical mucus is suboptimal.

OBJECTIVE: Cervical mucus is vital in the regulation of sperm survival and transport through the reproductive tract. The goal of this study is to assess whether the lowered fertility for men in their late 30s and early 40s is related to the nature of cervical mucus on the day of intercourse. METHODS: In a prospective study of 7 European family planning centers, 782 couples not using birth control recorded daily observations of intercourse and the nature of cervical mucus. Using data from 1,459 menstrual cycles, 342 ending in pregnancy, we estimate day-specific conception probabilities in relation to mucus and male and female age. RESULTS: On days where cervical mucus was not evident, intercourse for men in their late 30s and early 40s was 50% less likely to result in a clinical pregnancy, adjusting for intercourse timing and female age. As secretions become more conducive to sperm transport, the effect of male age diminishes steadily from 21% on days with damp secretions, to 11% on days with thick mucus, to only 4% on days with most fertile-type mucus. CONCLUSION: The effect of male age on fecundability can be minimized by timing intercourse on days with optimal secretions. LEVEL OF EVIDENCE: II-2.

Mucus observations in the fertile window: a better predictor of conception than timing of intercourse.

BACKGROUND: Intercourse results in a pregnancy essentially only if it occurs during the 6-day fertile interval ending on the day of ovulation. The strong association between timing of intercourse within this interval and the probability of conception typically is attributed to limited sperm and egg life times. METHODS: A total of 782 women recruited from natural family planning centres in Europe contributed prospective data on 7288 menstrual cycles. Daily records of intercourse, basal body temperature and vaginal discharge of cervical mucus were collected. Probabilities of conception were estimated according to the timing of intercourse relative to ovulation and a 1-4 score of mucus quality. RESULTS: There was a strong increasing trend in the day-specific probabilities of pregnancy with increases in the mucus score. Adjusting for the mucus score, the day-specific probabilities had limited variability across the fertile interval. CONCLUSIONS: Changes in mucus quality across the fertile interval predict the observed pattern in the day-specific probabilities of conception. To maximize the likelihood of conception, intercourse should occur on days with optimal mucus quality, as observed in vaginal discharge, regardless of the exact timing relative to ovulation.

Increased infertility with age in men and women.

OBJECTIVE: To estimate the effects of aging on the percentage of outwardly healthy couples who are sterile (completely unable to conceive without assisted reproduction) or infertile (unable to conceive within a year of unprotected intercourse). METHODS: A prospective fecundability study was conducted in a sample of 782 couples recruited from 7 European centers for natural family planning. Women aged 18-40 years were eligible. Daily intercourse records were used to adjust for timing and frequency of intercourse when estimating the per-menstrual-cycle probability of conception. The number of menstrual cycles required to conceive a clinical pregnancy and the probability of sterility and infertility were derived from the estimated fecundability distributions for men and women of different ages. RESULTS: Sterility was estimated at about 1%; this percent did not change with age. The percentage infertility was estimated at 8% for women aged 19-26 years, 13-14% for women aged 27-34 years and 18% for women aged 35-39 years. Starting in the late 30s, male age was an important factor, with the percentage failing to conceive within 12 cycles increasing from an estimated 18-28% between ages 35 and 40 years. The estimated percentage of infertile couples that would be able to conceive after an additional 12 cycles of trying varied from 43-63% depending on age. CONCLUSION: Increased infertility in older couples is attributable primarily to declines in fertility rates rather than to absolute sterility. Many infertile couples will conceive if they try for an additional year.

Changes with age in the level and duration of fertility in the menstrual cycle.

BACKGROUND: Most analyses of age-related changes in fertility cannot separate effects due to reduced frequency of sexual intercourse from effects directly related to ageing. Information on intercourse collected daily through each menstrual cycle provides the data for estimating day-specific probabilities of pregnancy for specific days relative to ovulation, and these estimates allow unconfounded analysis of ageing effects. METHODS: A total of 782 healthy couples using natural family planning methods contributed prospective data on 5860 menstrual cycles. Day of ovulation was based on basal body temperature measurements. Estimates of day-specific probabilities of pregnancy and the length of the fertile window were compared across age groups. RESULTS: Nearly all pregnancies occurred within a 6 day fertile window. There was no evidence for a shorter fertile window in older men or women. On average, the day-specific probabilities of pregnancy declined with age for women from the late 20s onward, with probabilities of pregnancy twice as high for women aged 19-26 years compared with women aged 35-39 years. Controlling for age of the woman, fertility was significantly reduced for men aged >35 years. CONCLUSIONS: Women's fertility begins to decline in the late 20s with substantial decreases by the late 30s. Fertility for men is less affected by age, but shows significant decline by the late 30s.