近年の大腸がんの高い罹患率により大腸がんによる死亡率も高くなり，現在のところ，がん死亡率でみると，男性では3位，女性では1位となっており，診断・治療とともに，その発見も重要な課題項目といえる．その点で大腸がん検診スクリーニングは大きな役割が期待されている．しかしながら，毎年ある程度の受診件数があるものの，精密検査対象者の受診率は他のがんと比較すると圧倒的に低い．このような背景のもと，本稿では大腸がん検診スクリーニングに関する現状と，関連する多くの検査手段について概観した．すなわち，検診のうち，対策型検診で中心となる便潜血検査法について，また，任意型検診，あるいは対策型検診の精密検査対象者への検査として，従来の検査法に加えて，新たな有力な検査法のいくつかについても概説を行った．これらの検査のメリット・デメリットを十分に理解することで，検診受診者に対しては，その情報を還元することにより，結果として，大腸がんの発見，ひいては死亡率の低下をもたらすことに繋がると思われる．

Objective: In prostate cancer screening in Ningen Dock, the PSA test is continuously carried out, enabling us to obtain a PSA curve for every man. Among examinees who underwent the Ningen Dock of Kurosawa Hospital, we compared PSA growth curves between normal men and prostate cancer patients.

Methods: The PSA growth curves of all male examinees (n=138,392, 30 to 79 years old) of the Ningen Dock at Kurosawa hospital were investigated. PSA growth curves were also investigated in 69 men who were found to have prostate cancer.

Results: PSA growth curves in men with prostate cancer were quite different from those without. In the former, there were three phases of PSA growth: a flat phase, a gently increasing phase and a sharply increasing phase. The pre-biopsy PSA, PSA doubling time (2nd + 3rd phase) and the duration of the 3rd phase affected the Gleason grade group.

Conclusion: If the 3rd phase, the PSA sharply increasing phase, is seen in an examinee, examination by a urologist should be recommended.

Objective: We investigated the status of H. pylori infection among endoscopic gastric cancer screening subjects according to the Kyoto classification of gastritis.

Methods: 460 subjects (251 males, mean age: 51.4 yrs.) who underwent upper endoscopic screening were included in our study. H. pylori-uninfected subjects were defined as having no gastric atrophy and visible RAC (regular arrangement of collecting venules) in the lesser curvature of the lower corpus, H. pylori-infected subjects as having diffuse redness and gastric atrophy, and H. pylori-past-infected subjects were defined as having gastric atrophy and no diffuse redness. Endoscopic gastric atrophy was diagnosed according to the Kimura-Takemoto classification.

Results: From the endoscopic findings, 295 subjects (64.1%) were diagnosed as H. pylori-uninfected, 50 (10.9%) as H. pylori-infected, and 115 (25%) as H. pylori-past-infected, based on the above definitions. The prevalence of H. pylori-uninfected subjects gradually decreased with age, while the prevalence of H. pylori-past-infected subjects gradually increased with age. In H. pylori-past-infected subjects, the prevalence of map-like redness was 22.6%, and this was accompanied by severe gastric atrophy.

Conclusions: The Kyoto classification of gastritis was very useful for determining the risk of gastric cancer. For patients with map-like redness after H. pylori eradication, it is very important to undergo regular endoscopic surveillance considering the possibility of developing gastric cancer.

Background: AICS (prostate) was developed based on “AminoIndex Technology”. It involves multivariate analysis of the plasma free amino acid (PFAA) concentration between prostate cancer patients and healthy subjects, and has recently been put into use as a screening test for prostate cancer. To clarify the characteristics of AICS (prostate) in screening, we evaluated post-operative changes in AICS (prostate) results in patients who underwent radical prostatectomy for prostate cancer.

Methods: Plasma samples were obtained from 64 recurrence-free patients who underwent radical prostatectomy for prostate cancer at Kanagawa Cancer Center, and compared with preoperative measurements. PFAA concentrations were measured by liquid chromatography-mass spectrometry. AICS (prostate) values and ranks were calculated using the developed index.

Results: After radical prostatectomy, AICS (prostate) values and ranks decreased in 88% (49/56) and 75% (42/56) of recurrence-free patients determined to be rank B or C before prostatectomy, respectively. For preoperative AICS (prostate) rank C patients, postoperative AICS (prostate) values and ranks decreased in 93% (39/42) and 79% (33/42), respectively.

Conclusion: The AICS (prostate) value and rank decreased in most patients after radical prostatectomy. As AICS (prostate) results reflect prostate cancer development, they could be a useful cancer screening marker.

Objective: The optimal method of interpreting diminutive polyps (≤5 mm) on standardized computed tomographic (CT) colonography in Japan has not been determined. To help standardize interpretation, for diminutive polyps, we investigated the diagnostic accuracy of CT colonography as well as factors aiding diagnosis and policies for interpreting findings.

Methods: We used total colonoscopy as a reference standard, and calculated positive predictive values (PPVs) for 50 diminutive polyps ≤ 5 mm detected by CT colonography. Additionally, we compared these PPVs with those of polyps ≥ 6 mm. We used multivariate analysis to investigate factors aiding the diagnosis of diminutive polyps. We also compared the time required to meticulously interpret all diminutive findings with the time taken to meticulously interpret high-confidence findings only.

Results: The per-polyp PPV was 100% (7/7) for polyps ≥ 10 mm, 62.5% (15/24) for polyps ≥ 6 mm, and 28% (14/50) for polyps ≤5 mm. The PPV was significantly lower for diminutive polyps. Height was a significant factor aiding diagnosis for diminutive polyps (cutoff: 1.5 mm). The median interpretation time when all diminutive findings were meticulously interpreted was 18 minutes and 14 minutes when only findings considered to be high-confidence were meticulously interpreted (p=0.02).

Conclusions: The PPV for diminutive polyps was low. We determined that height helps in diagnosing diminutive polyps. Meticulously interpreting only high-confidence diminutive findings may decrease the burden on CT readers. In Japan, a consensus for the interpretation of diminutive polyps on CT colonography will hopefully be reached.

Objective: Although Japan is gradually becoming a destination for medical tourism, the number of institutions offering comprehensive health check-ups for people from overseas seeking medical care is still small, due to concern over language and cultural differences. Here we report our first experience of providing comprehensive health check-ups (called “Ningen Dock” in Japanese) to visitors from overseas.

Methods: Between 2015 and 2017, 22 Chinese tourists (14 males and 8 females; mean age 49.2 years) underwent Ningen Dock at our institution. We evaluated the outcomes in four areas: communication, exam content, contractual matters, and effectiveness of measures against problems in examinations.

Results: Communication problems were minimized through the use of interpreters; however, slight problems did occur when the interpreter was simultaneously required for two different examinations. In the other three areas, there were no complaints or problems.

Conclusions: The Ningen Dock for foreign tourists was more successful than we had anticipated. Nevertheless, since many of the aspects of Ningen Dock are unique to Japanese medical culture, going forward, the focus should be on continuously adapting its approaches and models, in order to be positively evaluated by tourists from around the world.

Objective: At our facility, we carry out follow-up examinations for persons receiving active support in Specific Health Guidance with the purpose of improving dietary and exercise habits. We examined the usefulness of follow-up examinations for persons receiving Specific Health Guidance by comparing check-up data between those who received follow-up examinations and those who did not.

Methods: Among persons who underwent a comprehensive or general health check-up at our facility and received active support, 92 whose health check-up data was available for the following year were included in the study. They were divided into a group who received follow-up examinations and a group who did not. A comparison was made between the groups at the time of the follow-up examinations. Changes in health check-up data and decreases in metabolic syndrome (MetS) in the following year were also compared between the 2 groups.

Results: In the group with follow-up examinations, at the time of the examinations, there had been decreases in abdominal circumference, bodyweight and BMI as well as improvement in triglycerides, HDL cholesterol and fasting blood sugar. Also, in the health check-up in the following year, the weight reducing effect was maintained and so was the improvement in triglycerides and HDL cholesterol. There was also a 33% reduction in the number of people in the MetS category. On the other hand, no significant changes were observed in the group without follow-up examinations.

Conclusion: In persons receiving active follow-up and follow-up examinations, abdominal circumference and bodyweight decreased and clinical test results improved. Our findings suggested that follow-up examinations in Specific Health Guidance were an effective means of increasing the motivation of subjects as well as the effectiveness of guidance.

Objective: We elucidated the present situation of metabolic syndrome (MetS) and compared clinical characteristics between MetS individuals and those who had a normal abdominal circumference but fulfilled other criteria for diagnosis of MetS (masked MetS).

Methods: 21,668 examinees (men 13,126, women 8,542) were enrolled in this study.

Results: MetS was found in 19% of the men, and in 3% of the women, and its frequency increased with age. In masked MetS, abnormality in systolic and diastolic blood pressure was the most frequently observed criterion for MetS in the laboratory data of both men and women. In a comparison of mean values of laboratory data between MetS and masked MetS, in men, LDL-C, triglyceride, AST, ALT, γ-GTP and HbA1c were significantly higher in MetS, whereas systolic and diastolic blood pressure and HDL-C were significantly higher in masked MetS. As for women, γ-GTP in MetS and HDL-C in masked MetS were significantly higher. Smoking habit was more common in masked MetS, in men. Drinkers were significantly in the majority in masked MetS, in men, while non-drinkers were significantly in the majority in MetS, in women. There was no difference in past medical history between MetS and masked MetS, both in men and women.

Conclusion: Our findings suggested that we should continue existing guidance for those with MetS. For those with masked MetS, in addition to guidance on MetS, that on smoking and drinking should also be given, in consideration of individual diathesis.

  A 64-year-old woman had been positive for fecal occult blood for three consecutive years in occupational health check-ups, but this was not followed up. She developed orthostatic dizziness and pain upon defecation, but did not consult a physician. Thereafter, she was diagnosed with anemia and consulted a doctor who diagnosed advanced rectal cancer and early colon cancer. Pretreatment examination also revealed gallbladder cancer. She developed ileus due to bowel preparation for endoscopic therapy to be performed for early colon cancer and required construction of an artificial anus. The colon and gallbladder cancers were treated endoscopically and surgically, respectively. Chemotherapy is currently being administered for the rectal cancer.

  Although rates of colorectal cancer have recently increased, rates for secondary testing following colorectal cancer screening are generally low, and they are lower for occupational health check-ups than for local health check-ups. Education on colorectal cancer would lead to enhanced awareness of the need for examination and it would be important to combine this with appropriate encouragement to undergo it.

  Rates of multiple primary cancers have been tending to increase together with the aging of the population and advances in diagnostic imaging. Although multiple primary cancers of the colon and gallbladder are rare, there is a visible increasing trend. In cancer screening, it is important to confirm whether cancer predilection and multiple factors are present or not through history taking, physical and other examinations. Knowledge of multiple primary cancers is required even for medical staff engaged in general health check-ups.