In order to quantitatively clarify the effect of breast cancer screening, we analyzed the extension of lifespan by simulation using a mathematical model that estimated parameters from the situation regarding breast cancer in Japan. In this mathematical model, the number of people changes every year after birth depending on the morbidity and mortality rate of breast cancer in addition to the general mortality rate according to each age. For breast cancer, different stage-specific mortality rates and stage progression rates were estimated from clinical data and used. For cancer screening, we calculated how much life expectancy would increase in some cases with different intervals and target ages. From the results of the simulation, it was estimated that breast cancer screening every other year for individuals aged 40 to 79 years could be expected to extend their lifespan by 93.6 days (about 3 months). The results showed that life expectancy was extended by 5.78 years for those who suffered from breast cancer at the age of 40. On the other hand, during the 30-year examination period, one person experienced one or more false positives (about 1.3 times). In recent years, there has been increasing interest in overdiagnosis and adverse events in screening, and it is necessary to make comparisons and evaluations in balance with these. We proposed a comprehensive judgment criterion that takes individual differences into consideration.

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[in Japanese]

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Human beings often make irrational choices of biases and their feature of thinking, even when they believe they made rational choices under sufficient information. Taking into account the behavioral-economic nature of humans, “nudge” is the design or architecture to promote people to make a preferable choice for themselves. In recent years, nudges have been increasingly used in the field of public health. In Japan, materials for promoting cancer screening with nudges have been published. These materials were verified that they increased the number of people who have cancer screening including breast cancer screening. Nudge is based on the theory of ethical and political philosophy called libertarian paternalism. In this theory, the value of a person is realized at a higher level by guiding with some amount of induction toward his/her purpose, compared with the case where a person's liberty is put highest priority. However, despite the validity at the level of the principle of the theory, nudge cannot avoid being questioned in its ethical soundness. There are some ethically-concerned cases such as non-educational nudges or nudging in an inappropriate direction for the target person. Considering these ethical concerns, it would be desirable to involve citizens in the process of system design to construct a cancer screening system that reflects sound information and the values of the general public.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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Risk assessment based on gemline genomic mutation becomes important issue in cancer screening. We have conducted SEIREI-CARE (comprehensive assessment, risk and education) program, a genetic/familial assessment of breast, ovarian and pancreatic cancers, using next-generation sequencing multigene panel (MGP) testing. An artificial intelligence (AI) chatbot device is utilized to assess cancer risk according to the National Comprehensive Cancer Network Guidelines. From April to September 2021, 1,117 women out of 10,742 (10.6%) registered through AI chatbot, and 285 (24.9%) of them met the NCCN Guideline. The rate of clinical genetic counseling is limited to 9.1%, accordingly only 3 women tested by MGP during 6 months. An integrated and functional approach is required for nursing profession and medical staff to promote genetic medicine.

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We investigated the frequency of development of axillary lymphadenopathy after COVID-19 vaccination in women who underwent breast cancer screening ultrasonography. All the subjects had received Pfizer’s COMIRNATY vaccine by intramuscular injection and underwent ultrasonographic examination of the breast and bilateral axillae for breast cancer screening. The ultrasonographic images were reviewed for the presence of hyperechoic areas reflecting the axillary lymph nodes, the state of the cortex, and the fat tissue in the lymph node hilum. Presence of enlarged lymph nodes was assessed by comparison with the findings on ultrasonography performed the previous year. In addition, the frequency of lymphadenopathy was examined by age and number of vaccinations. Of the total of 115 subjects enrolled in this study, 87 (76%) were found to have axillary lymphadenopathy. Hyperreactive lymphadenopathy, represented by enlargement with cortical thickening and loss of the hyperechoic hilum, was observed in 53 cases (46%). After the first vaccination, lymphadenopathy was observed in 54 (79%) of 68 subjects. The incidence of lymphadenopathy was similar across all age groups. However, the incidence of hyperreactive lymphadenopathy with cortical thickening and loss of the hyperechoic hilum tended to be higher in younger subjects. Breast cancer screening revealed a high frequency of unilateral axillary lymphadenopathy associated with COVID-19 vaccination. Guidelines are beginning to be released overseas and in Japan, regarding the timing of breast cancer screening vis-a-vis COVID-19 vaccination. It may become difficult to make the assessment if the vaccination becomes routine in the future. Before scheduling breast cancer screening, it is important to have a thorough knowledge about the development of unilateral axillary lymphadenopathy associated with COVID-19 vaccination.

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Purpose To elucidate the mammographic and clinicopathological features of well-circumscribed masses (WCMs) detected on digital breast tomosynthesis (DBT). Materials and methods Findings of a total of 555 consecutive WCM lesions in 266 women detected on DBT between August 2016 and March 2021 were retrospectively reviewed. The clinicopathological and digital mammography (DM) features were correlated with the DBT features of the WCM lesions. Results The average age of the subjects was 55 years. Most of the WCMs were benign (531/555, 95.8%), with cancer accounting for only 4.3% (24/555) of all the cases. On DM, 41.6% (231/555) were classified as C1 (negative), and 3.5% (8/231) of these were eventually diagnosed as cancer. Univariate analysis identified WCM density on DBT, the maximum lesion diameter, and the maximum/minimum diameter ratio as significant factors for differentiating between benign and malignant lesions. Multivariable analysis identified only lesion density as a significant independent factor, with a sensitivity/specificity/accuracy/positive predictive value (PPV)/negative predictive value (NPV) of 45.8%/78.5%/77.1%/8.8%/97%. When the highest priority was placed on the sensitivity, a cutoff value for the largest diameter of 7.9 mm was found to be associated with a sensitivity/ specificity/ accuracy/PPV/NPV of 100%/38.6%/41.3%/PPV 6.9%/NPV 100%. Conclusion About 95% of WCMs detected on DBT were benign lesions. Our results suggest the false-positive rate may be lowered by excluding small lesions (‹7.9mm), without also missing any cases of breast cancer.

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We conducted retrospective observational study in Japanese women to compare the diagnostic performance and characteristics between full-field digital mammography (FFDM) and synthesized two-dimensional mammography (s2D). The participants were 100 women (malignant: 43 cases; normal or benign: 57 cases) who underwent mammography for diagnostic/opportunistic screening at our institution between January 2017 and April 2018. The mean diagnostic sensitivity (by 6 observers) of s2D (72.1%) was higher than that of FFDM (62.0%). The mean specificity was almost equivalent, at 78.0% and 77.8%, respectively. There was no statistically significant difference of the mean figure of merit (FOM) between FFDM (0.637) and s2D (0.693)(p = 0.107).The mean sensitivity determined for each of the imaging findings revealed a significant difference only for architecture distortion, and there were category discordances between FFDM and s2D for all the findings. In Japanese women, s2D showed equal or better diagnostic performance than FFDM. Therefore, abbreviating FFDM and replacing s2D should be considered, because of the higher radiation dose exposure when digital breast tomosynthesis is applied. In addition, it is important to understand the differences in the characteristic imaging findings between FFDM and s2D.

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Purpose: According to the current guidelines for breast ultrasound diagnosis, all intraductal lesions require further examination. However, this could lead to unnecessary examinations, as many intraductal lesions detected during examination, such as intraductal papillomas, are benign. Therefore, we retrospectively reviewed the characteristics of intraductal lesions detected during screening and explored potential imaging criteria that could help determine the necessity of further examinations. Subjects and Methods: A total of 334 intraductal lesions treated at our institution between January 2016 and December 2020 were included, and their morphology, size, blood flow, and elastographic findings were examined. The morphology was classified into four categories (1) sharply rising, (2) gradual, (3) filling of the duct with solid lesions, and (4) mass-like appearance contiguous with the duct. Results and Discussion: Among the intraductal lesions, breast cancer was found in only nine (2.7%) cases or 0.04% examinees, and 97.3% cases were false-positive cases according to the current criteria. In addition, none of the sharp lesions or lesions measuring ‹5 mm were found to be cancerous. Eight of the nine breast cancer cases showed flow signals, and the remaining one case without flow signals was a case of low-grade ductal carcinoma in situ measuring 3 mm in diameter. Therefore, if further examinations had been waived for sharp lesions or lesions measuring ‹5 mm in diameter, 186 (55.7%) of the 334 cases would not have undergone further examinations. Furthermore, if the waiver could be extended to lesions without flow signals, 269 (80.5%) of the 334 cases would not have undergone further examinations. Conclusion: Application of these criteria could possibly reduce the number of false-positive cases without overlooking lesions that could potentially be breast cancer.

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Based on our patients' history of breast cancer, their most frequent motive for visiting the hospital was roughly categorized into three: noticed anomalies on self-checkup (Sel), abnormality was pointed out after mammography screening conducted by the government (Gov) , or abnormality was pointed out after mammographic screening at a routine facility examination (Fac). Then, we verified the hypothesis that the distribution of the tumor location found by Sel is consistent with the original location of the tumor. We compared the regional distribution of breast cancer onset in these three groups. From 2010 to 2021, we included 3005 patients, classified into the Sel, Gov, or Fac group. From the Fac group, we excluded the patients who had visited the home doctor with the Sel or Gov group. In the Sel group, the location of the main abnormality was classified into the ABCDE regions (n (%): A: 392 (25.3%), B: 154 (9.9%), C: 689 (44.5%), D: 153 (9.9%), E: 160 (10.3%)). As compared with the Sel group, no significant difference was found in the location distribution of the lesions in the Fac group: (A: 83 (23.1%), B: 35 (9.7%), C: 151 (41.9%), D: 47 (13.1%), and E: 44 (12.2%), p=0.3053). However, the Gov group showed a significant difference in the location distribution as compared with both the other groups: (A: 214 (26.7%), B: 63 (7.8%), C: 366 (45.6%), D: 102 (12.7%), E: 58 (7.2%), p=0.0144). There was a dissociation from other detection methods, and a possible weakness of mammographic screening in detecting lesions in the E region was revealed. Mammographic screening organized by the government was rather superior to institutional checkups in terms of the stage at detection (p<0.0001, our data), but it may be less sensitive to abnormalities in the E region.

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