Early diagnosis is essential to improve the treatment outcome of pancreatic cancer, which is considered to have a poor prognosis. In 2007, Onomichi Medical Association started a program for early diagnosis of pancreatic cancer (PC) focusing on risk factors. For these thirteen years, results such as an increase of PC with early diagnosis, improvements in surgical resection rates, and five-year survival rates have been reported. In recent years, similar efforts have been reported in more than 30 locations in Japan, and results similar to those of the Onomichi district have been reported in the Osaka or Kishiwada districts. These results suggest that the project for early diagnosis of PC focusing on risk factors may improve the prognosis of PC.

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[in Japanese]

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According to the advance in imaging diagnosis and the spread of core needle biopsy and vacuum-assisted biopsy, a lot of proliferative lesions in mammary ducts and lobules have been detected and histologically classified. Risks of these lesions as precursors of cancer or indicators of concurrent cancer have been evaluated mainly by retrospective studies, and atypical ductal hyperplasia (ADH), atypical lobular hyperplasia (ALH), and lobular carcinoma in situ (LCIS) are regarded as such high-risk lesions. In early days, patients diagnosed to have these lesions on needle biopsy received excision of surrounding tissues. However, recently, the manner of their management is going to change, and safety of active surveillance is investigated. The upgrade rates of intraductal papillomas have been shown to differ between papillomas with and without atypia, and follow-up is shown to be allowed to the latter group because of low upgrade rate. Since there are few data on upgrade rate or follow-up of high-risk lesions in Japan, studies on biology and management of these lesions appear necessary.

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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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[in Japanese]

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[in Japanese]

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[in Japanese]

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The guidelines published by the International Atomic Energy Agency set acceptable and achievable values for the signal difference-to-noise ratio (SDNR) of each phantom thickness for each device,and they are values that have not been set in other guidelines. The acceptable and achievable values of the SDNR and the mean glandular dose (MGD) were evaluated by indirect flat panel detector (FPD) mammography,direct FPD,and computed radiography mammography. The SDNR increased with the increase in MGD in each device and each polymethyl-methacrylate phantom thickness. In addition,the SDNR for a phantom thickness of 20 mm exceeded the acceptable value with the MGD below the acceptable value for all devices. For phantom thicknesses of 45 mm and 70 mm,some devices did not exceed the SDNR acceptable values, although the MGD had increased. If the MGD below the acceptable value does not exceed the acceptable SDNR value,it is necessary to avoid clinical use and adjust the tube voltage and target/filter. The settings of digital mammography devices can be adjusted by defining the acceptable and achievable values.

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The mammography equipment used for breast cancer screening in Japan must meet the standards of the Japan Radiological Society. Mammography is considered to have been replaced by digital systems, and soft-copy diagnosis has become mainstream. However, there have been no reports of investigations of system replacement in Japan. In this study we investigated the replacement of mammography systems by counting the numbers of systems from 2009 to 2019. The data used in this study were obtained from the “Monthly New Medical Journal”, which contains a list of mammography facilities during the 11 years from 2009 to 2019. During that period, the numbers of mammography systems increased, the numbers of analog systems decreased, and the numbers of digital systems increased. In 2019, 53.2% of the systems were analog systems, and 46.8% were digital systems, but since some FPD installation data were missing, we assume that the number of digital systems was about the same or even higher than the number of analog systems. This study is a compilation of references, and although the actual numbers of vendor installations and the numbers of installations by prefecture in it may differ from the actual number, it is useful as a means of understanding the trends in system replacement from 2009 to 2019.

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Softcopy reading has become the mainstream method of diagnosis in digital mammography. High -resolution color monitors that allow interpolation between multiple modalities have become available in recent years, and high-resolution 4K tablets are also becoming popular for consumer use. In this study we compared the physical characteristics of medical color monitors and 4K tablets, and we used a CCL550i2/AR 5MP color monitor, Coronis Uniti MDMC-1213312MP color monitor, and UT-MA4 4K tablet to make the comparisons. The measurements were made with NS-2007 (S.S. Giken), and we used a Nikon D80 camera. The values measured were uniformity, MTF, and NPS. The uniformity of the 5MP and 12MP color monitors was comparable, but the 4K tablet was inferior to the 5MP and 12MP color monitors. NPS was also poorer with the 4K tablet than with the 5MP and 12MP color monitors. The differences may have been attributable to pixel size and sub-pixel structure. The results indicate that the 4K tablet used in this study is suboptimal for use as a reading terminal. However, 4K tablets have “higher resolution” and “higher MTF” than medical monitors, and they are compatible with GSDF curves. Thus, 4K tablets are expected to be used for learning and training in mammography reading instead of general-purpose monitors. However, since the physical characteristics of the 4K tablet are inferior to those of medical monitors, it will be necessary to confirm that the diagnostic results obtained with the 5MP can be adequately depicted on the 4K tablet.

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A new system of postcard notification and individual screening was introduced for breast cancer screening in Onojo city, in which our clinic specializing in breast cancer participated for the first time. There were 2,191 citywide examinees in 2020, which significantly increased from 1,656 in 2019. Overall, 398 examinees (18.2%) visited our clinic. The low rates of examinees with an appropriate screening interval (50.3%) and breast self−examination rate (38.4%) suggested insufficient breast cancer awareness. The process index for screening at our clinic were as follows: cancer detection rate: 3/398 (0.75%), including 2 cases with early breast cancer; recall rate: 12.3%; work−up examination rate; 95.5%; and positive predictive value: 6.8%. Definitive diagnosis using core needle biopsy after recall in our clinic contributed to patients with breast cancer being immediately introduced to a surgical facility (31 days in our clinic vs. 71.4 days after screening at other facilities).The questionnaire indicated that individual notifications was motivating factors for screening. In conclusion, the number of citywide examinees significantly increased by the introduction of this new system. Several advantages of an individual screening at our clinic were also recognized. The higher recall rate (12.3%), a demerit of individual screening, can be improved by comparative readings from upcoming continuous screening at our clinic.

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For the purpose of verifying the significance of breast awareness by analyzing cases referred from our institution, we examined the effectiveness of breast awareness using the detection rate of early breast cancer as a surrogate for mortality. Breast awareness and screening contribute to early cancer detection. However, additional benefits of self-breast examination are small. Although self-breast examination itself has little impact on early cancer detection, there is an association between self-breast examination and screening uptake. Especially, it is important for women to be concerned about their breast in order to motivate them to undergo breast cancer screening.

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T1a breast cancer with a tumor diameter of 5 mm is classified as microcarcinoma. In general, lymph node metastasis is rare, and the prognosis is relatively good, with a 5-year survival rate of ≥95%. Therefore, chemotherapy is not often used. However, depending on the histological type and other characteristics of the tumor, some patients show a rapid clinical course. Therefore, early detection of T1a breast cancer is also important. Under these circumstances, we decided to review cases of T1a breast cancer treated at our hospital. We retrospectively reviewed the data of T1a breast cancer patients who had undergone surgery at our hospital between April 2015 and March 2022. A total of 6 patients were included. The mean age was 65.8 ± 11.3 years, and all were women. Breast cancer was diagnosed by mammographic (MMG) screening in 4 of these patients and by palpation of a lump in the remaining 2 patients. The MMG findings were calcification in 3 cases and breast architectural distortion in 1 case. The subtype was luminal A in 2 cases, luminal B in 2 cases, human epidermal receptor 2 (HER2) in 1 case, and triple-negative (TN) in 1 case. The histological type was invasive ductal carcinoma (IDC) in 5 cases and invasive micropapillary carcinoma (IMPC) in 1 case. Of all the cases of T1a breast cancer treated at our hospital, we started treatment after the screening in 67%, suggesting that early detection and early treatment was possible in these patients. The cases included relatively highly malignant breast cancers, such as those with strong HER2 expression, TN, and IMPC. Many of the T1a breast cancer patients did not receive chemotherapy. Therefore, the detection of breast cancers measuring 5 mm in diameter by breast screening not only improves the cure rate of breast cancer, but is also of socioeconomic significance.

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The patient was a 57-year-old woman who had undergone breast augmentation with hyaluronic acid injections about 5 years earlier. No shrinkage was noted even after 5 years, and the patient had had no problems related to the breast augmentation procedure. She had been undergoing breast cancer screening by mammography and ultrasonography on a regular basis. She presented to our clinic with an abnormality detected during a check-up conducted using a countermeasure type breast cancer screening ultrasonography. At her first visit to our clinic, clinical examination by palpation revealed a large mass occupying the entire lower portion of both breasts. Ultrasonography of the breast confirmed the presence of a cystic mass in the lower portion of both breasts. We encountered a case in which the injectate, namely, hyaluronic acid, used for breast augmentation was not absorbed and resulted in the formation of a huge cystic mass in both breasts.

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