Performance profile of a FDG-PET cancer screening program for detecting gastric cancer: results from a nationwide Japanese survey

Purpose

It has been reported that gastric cancer is the sixth most common cancer found during the ¹⁸F-fluorodeoxyglucose-positron emission tomography (FDG-PET) cancer screening program, which is defined as cancer screening of asymptomatic subjects using FDG-PET(/CT) (in combination with other screening tests or not). The aim of this study was to analyze the detection rate and the effectiveness of the FDG-PET cancer screening program at detecting gastric cancer between 2006 and 2009 in Japan.

Materials and methods

A total of 153,775 asymptomatic subjects (92,255 men, 61,520 women) between 30 and 80 years old underwent the FDG-PET cancer screening program. Of these, we analyzed 790 cases with findings of possible gastric cancer in any screening test.

Results

The number of cases who were verified to have gastric cancer was 124. Among these, only 47 cases were detected by FDG-PET, which resulted in a relative sensitivity of 37.9 % and a positive predictive value of 33.6 %. The relative sensitivity of FDG-PET was much lower than those of gastric endoscopy and the serum pepsinogen test.

Conclusion

The FDG-PET screening program in Japan detected some cases of early-stage gastric cancer, but this was not achieved using FDG-PET alone but in combination with gastric endoscopy. Gastric endoscopy should be included in FDG-PET cancer screening programs to screen for gastric cancer.     

Performance profile of FDG-PET and PET/CT for cancer screening based on a Japanese nationwide survey

A total of 50,558 healthy subjects underwent an FDG-PET (including PET/CT) scan with or without combination of other tests for cancer screening in 46 PET centers during fiscal year of 2005 in Japan. Thorough examination was indicated for 9.8% of the cases due to positive findings suggesting possible cancer. On analyzing 43,996 cases from 38 PET centers, where detailed information was obtained, 500 cases of cancers (1.14%) were found, of which 0.90% was PET positive and 0.24% was PET negative, resulting in the relative sensitivity of PET being 79.0%. Cancers of thyroid, colon/rectum, lung and breast were most frequently found (107, 102, 79, 35 cases, respectively) with high PET sensitivity (88%, 90%, 80%, 92%). PET showed an overall positive predictive value of 29.0%. PET/CT had better detection rate, sensitivity, and positive predictive value than dedicated PET (p<0.01).     

Analysis of various malignant neoplasms detected by FDG-PET cancer screening program: based on a Japanese Nationwide Survey

Objective

The most distinctive feature of FDG-PET cancer screening program is the ability to find various kinds of malignant neoplasms in a single test. The aim of this survey is to clarify the range and frequency of various malignant neoplasms detected by FDG-PET cancer screening performed in Japan.

Methods

“FDG-PET cancer screening” was defined as FDG-PET or positron emission tomography and computed tomography (PET/CT) scan with or without other tests performed for cancer screening of healthy subjects. This survey was based on a questionnaire regarding FDG-PET cancer screening. We analyzed the situation of 9 less frequently found malignant neoplasms including malignant lymphoma, malignancy of head and neck, esophagus, hepatobiliary and gallbladder, pancreas, kidney, cervical and uterine, ovary, and bladder.

Results

The detailed information of subjects with the suspected 9 kinds of malignant neoplasms mentioned above in the FDG-PET cancer screening program was studied in a total of 1,219 cases from 212 facilities. A statistical significance between PET/CT and PET was found in relative sensitivity and PPV for renal cell cancer. Malignant lymphoma was frequently of indolent type, suspected head and neck cancers had many false-positive results, and pancreatic cancer detected in this program was often in the advanced stage even in asymptomatic subjects. The recommendation of combined screening modality to PET or PET/CT was as follows: gastric endoscopy for assessing early esophageal cancer; abdominal ultrasound for screening hepatobiliary and gallbladder cancer; pelvic magnetic resonance imaging for assessing gynecological and pelvic cancers; and the CA125 blood test for screening ovarian cancer. Delayed image was helpful depending on the type of suspected malignant neoplasm.

Conclusion

We analyzed various types of malignant neoplasms detected by the FDG-PET cancer screening program and presented recommended combination of examinations to cover FDG-PET and PET/CT.     

Adverse events during CT colonography for screening,diagnosis and preoperative staging of colorectal cancer: a Japanese national survey

Objectives

To retrospectively evaluate the frequencies and magnitudes of adverse events associated with computed tomographic colonography (CTC) for screening, diagnosis and preoperative staging of colorectal cancer.

Methods

A Japanese national survey on CTC was administered by use of an online survey tool in the form of a questionnaire. The questions covered mortality, colorectal perforation, vasovagal reaction, total number of examinations, and examination procedures. The survey data was collated and raw frequencies were determined. Fisher’s exact test was used to determine differences in event rates between groups.

Results

At 431 institutions, 147,439 CTC examinations were performed. No deaths were reported. Colorectal perforations occurred in 0.014% (21/147,439): 0.003% (1/29,823) in screening, 0.014% (13/91,007) in diagnosis and 0.028% (7/25,330) in preoperative staging. The perforation risk was significantly lower in screening than in preoperative staging CTC procedures (p?=?0.028). Eighty-one per cent of perforation cases (17/21) did not require emergency surgery. Vasovagal reaction occurred in 0.081% (120/147,439): 0.111% (33/29,823) in screening, 0.088% (80/91,007) in diagnosis and 0.028% (7/25,330) in preoperative staging.

Conclusions

The risk of colorectal perforation and vasovagal reaction in CTC is low. The frequency of colorectal perforation associated with CTC is least in the screening group and greatest in the preoperative-staging group.

Key points

? The colorectal perforation rate during preoperative-staging CTC was 0.028?%.? The perforation rates for screening and diagnosis were 0.003?% and 0.014?%, respectively.? The perforation risk is significantly lower in screening than in preoperative staging.? Eighty-one per cent of perforation cases did not require emergency surgery.? Use of an automatic colon insufflator can reduce the risk of bowel perforation.

     

Internet use in radiology: results of a nationwide survey

PURPOSE: To determine the number of radiologists who currently have Internet access, their use patterns on the Internet for Radiology purposes, the web sites they would recommend, and the potential site access to the Internet that they would like to see in the future. In addition, this study analyzed the best way to find nationwide radiological sites and their content. MATERIALS AND METHODS: In a nationwide survey, 854 Austrian radiologist were asked to fill out and return a questionnaire about Internet access, current problems, current and future use, which web site they recommend, and about the use of e-mail. Next, the available nationwide radiological sites were searched with seven major search engines using 37 different keywords, as well as by category search, and by searching for links on the homepages of the radiological departments of all Universities of Austria. Then, the offered information of the founded pages was classified in categories. RESULTS: Of the 210 (24.6%) radiologists who returned the questionnaire, 154 (73%) had Internet access. Time expenditure was considered the main problem using the Internet. The Internet was used for literature research by 69% of the radiologists with Internet access, for e-mail by 60%, and for congress information by 57%. In future, 43% would like to read electronic journals more often and 39% would like to use the web more intensively for scientific congresses. At the present time, we found 17 radiological web sites in Austria. The most promising way to find these sites was to use the search engines Alta Vista and Hotbot. Fifteen (88%) sites offered information for patients, seven (41%) for radiologists, five (29%) for students, and four (24%) for researchers. SUMMARY: Many radiologists in Austria already have Internet access, although time expenditure was considered the main problem with Internet use. Survey responses showed a need for electronic journals. To our point of view, Universities and radiological societies are urged to publish journals electronically on the Web. Alta Vista and Hotbot were the best search engines for radiological sites in our setting, and a careful reading of the specific search engine's instructions is recommended. In our experience, Web pages with clear structure, small file size, precise HTML keyword editing, and page titles, facilitate more accurate discovery of specific sites. In addition, there seems to be a need for regular publication of reviewed radiological link collections and the establishment of standards for teleconsulting.     

Performance profile of FDG-PET and PET/CT for cancer screening on the basis of a Japanese Nationwide Survey

Objective The aim of this study is to survey the situation of ¹⁸F-fluorodeoxyglucose-positron emission tomography (FDG-PET) cancer screening in Japan and to describe its performance profile. Methods “FDG-PET for cancer screening” was defined as FDG-PET or positron emission tomography and computed tomography (PET/CT) scan with or without other tests performed for cancer screening of healthy subjects. We sent questionnaires regarding FDG-PET cancer screening to 99 facilities in which FDG-PET tests were performed during the fiscal year 2005. Replies were obtained from 68 of the 99 facilities, of which 46 facilities performed FDG-PET cancer screening. The total number of subjects who underwent FDG-PET cancer screening was 50 558. From 38 of 46 facilities, reliable results of thorough examinations were obtained for the subjects who were positive by FDG-PET and/or one or more of the combined screening tests was performed and were referred for further evaluation. The total number of subjects in these 38 facilities amounted to 43 996. Results A total of 50 558 healthy subjects underwent FDG-PET (including PET/CT) scanning with or without other tests for cancer screening in 46 PET centers during the fiscal year of 2005 in Japan. Thorough examination was indicated for 9.8% of the cases as a result of positive findings suggesting possible cancer. On analyzing 43 996 cases from 38 PET centers from which detailed information was obtained, 500 cases of cancers (1.14%) were found, of which 0.90% were PET positive and 0.24% were PET negative, resulting in the relative sensitivity of PET being 79.0%. Cancers of the thyroid, colon/rectum, lung, and breast were most frequently found (107, 102, 79, and 35 cases, respectively) with high PET sensitivity (88%, 90%, 80%, and 92%). PET showed an overall positive predictive value of 29.0%. PET/CT had a better detection rate, sensitivity, and positive predictive value than dedicated PET (P < 0.01). Conclusions We were able to clarify the performance profile of “FDG-PET for cancer screening” on the basis of a Japanese nationwide survey. The number of facilities possessing PET is increasing steadily, highlighting the necessity of evaluating the usefulness of “FDG-PET cancer screening” as soon as possible by undertaking long-term investigations of large series of subjects.     

Corporate-sponsored breast cancer screening at the work site: results of a statewide program

Mobile screening mammography was offered to 3,627 employees of a large corporation in Pennsylvania and Delaware. The examination was available to women employees or employee spouses aged 35 years and older. Women were charged $30 for a standard two-view examination. They also received health education materials on mammography and breast self-examination. The remaining costs of the program were underwritten by the corporation. During this program, 3,627 mammographic studies were performed; 63 biopsies were recommended. Fifty-seven biopsies were performed, and nine cancers were diagnosed. Costs of this program are presented in detail. The authors conclude that mobile screening programs at the work site provide an inexpensive, convenient alternative to more traditional screening programs. The inherent advantages of this program are the low cost, the relative ease with which the examination can be performed, and the positive role that corporate medical personnel assume in encouraging individual and group participation.     

Radiation exposure in multi-slice versus single-slice spiral CT: results of a nationwide survey

Multi-slice (MS) technology increases the efficacy of CT procedures and offers new promising applications. The expanding use of MSCT, however, may result in an increase in both frequency of procedures and levels of patient exposure. It was, therefore, the aim of this study to gain an overview of MSCT examinations conducted in Germany in 2001. All MSCT facilities were requested to provide information about 14 standard examinations with respect to scan parameters and frequency. Based on this data, dosimetric quantities were estimated using an experimentally validated formalism. Results are compared with those of a previous survey for single-slice (SS) spiral CT scanners. According to the data provided for 39 dual- and 73 quad-slice systems, the average annual number of patients examined at MSCT is markedly higher than that examined at SSCT scanners (5500 vs 3500). The average effective dose to patients was changed from 7.4 mSv at single-slice to 5.5 mSv and 8.1 mSv at dual- and quad-slice scanners, respectively. There is a considerable potential for dose reduction at quad-slice systems by an optimisation of scan protocols and better education of the personnel. To avoid an increase in the collective effective dose from CT procedures, a clear medical justification is required in each case.     

Physician satisfaction with high-resolution CT services provided by radiologists: results of a nationwide survey of pulmonary subspecialists

OBJECTIVE: Our objectives were to measure the level of satisfaction of pulmonary medicine specialists who refer patients to radiology facilities for high-resolution CT and to identify determinants of their reported satisfaction. MATERIALS AND METHODS: We surveyed 450 pulmonologist members of the American College of Chest Physicians. The self-administered questionnaire sought information about the radiologists and imaging facilities to which these clinicians referred patients for high-resolution CT of the lungs. The participants rated their satisfaction with the radiology services, estimated the number of patients referred for high-resolution CT per month, answered questions about certain attitudes and utilization practices, and provided general demographic information. RESULTS: Completed surveys were received from 230 pulmonologists practicing in 43 states. Satisfaction with high-resolution CT services was rated as follows: very satisfied (35% of respondents), satisfied (49%), and indifferent or dissatisfied (16%). A higher rating was found in pulmonologists in academic practice, in those who believed that the radiologists desired as much clinical information as possible, and in those who believed that two or more members of the radiology group were interested in high-resolution CT. Among satisfied pulmonologists, confidence in the radiologist's high-resolution CT interpretation was very important. Physician satisfaction was not significantly associated with the size of the radiology group or the number of monthly referrals for high-resolution CT. CONCLUSION: Pulmonologists in the United States appear to be satisfied with the high-resolution CT services provided by the radiologists in their communities. Satisfaction with radiology services might be further increased if radiologists expressed greater interest in high-resolution CT and pertinent clinical information and improved their interpretive skills.     

Results of a nationwide survey of chest radiography: comparison with results of a previous study

PURPOSE: To provide public health information by means of measurement of the radiation exposures that patients undergoing chest radiography would receive and to compare the results with those of a similar previous survey. MATERIALS AND METHODS: Surveyed facilities were randomly selected from each state. Patient exposure was evaluated along with film processing, half-value layer, and image quality. Additional information obtained concerned type of equipment, facility work load, radiographic technique, screen-film system, and grid type. RESULTS: Mean entrance air kerma in all facilities was 141 microGy (16.1 mR). Mean kilovoltage in all facilities was 101 kV. In 1994, 140 (90%) of 156 hospitals (vs 71% in 1984) and 92 (58%; nearly double the percentage in 1984) of 159 nonhospital sites were using grids. Scoring with the imaging test tool resulted in a mean spatial resolution of 2.3 cycles per millimeter, and a mean low-contrast sensitivity of about 3%. Two hundred fifty-three (80%) of 315 facilities surveyed were processing film at minimum acceptable performance levels. CONCLUSION: Mean entrance air kerma for all facilities did not substantially change. Although increased grid usage would lead to the expectation of higher measured exposures, this was offset by an increase in the use of faster screen-film combinations.     

Mammography screening for breast cancer: Four years of nationwide screening in Finland

Biennial breast cancer screening with two-view screen-film mammography started on a nationwide basis in Finland in January 1987. Women have been invited by birth year cohort to attend a free-of-charge examination. The program has progressively expanded to include two or three new birth year cohorts yearly of women between 50 and 59 years of age. Participation has averaged 89% and the breast cancer detection rate has ranged from 3.8 to 3.3 per thousand compared with an expected annual incidence of breast cancer in this age group of 1.6 per thousand. The positive predictive value has increased from 33% to 53%. Results to date, collected by the radiologists responsible for each screening centre, indicate an acceptable sensitivity and specificity for the program. Specificity is much better than that which had generally been considered possible or practical. Double reading of all films, intensive training in both mammography and mammography screening, and careful evaluation of ongoing results by the radiologists involved are all believed to be important factors leading to a high sensitivity and specificity of mammography screening. Correspondence to: M. Pamilo     

Improved detection of breast cancer on FDG-PET cancer screening using breast positioning device

Objective The aim of this study was to investigate the detection rate of breast cancer by positron emission tomography cancer screening using a breast positioning device. Methods Between January 2004 and January 2006, 1,498 healthy asymptomatic individuals underwent cancer screening by fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) at our institution; 660 of 1498 asymptomatic healthy women underwent breast PET imaging in the prone position using the breast positioning device to examine the mammary glands in addition to whole-body PET imaging. All subjects that showed abnormal ¹⁸F-FDG uptake in the mammary glands were referred for further examination or surgery at our institution or a local hospital. Our data were compared with the histopathological findings or findings of other imaging modalities in our institution and replies from the doctors at another hospital. Results Of the 660 participants, 7 (1.06%) were found to have breast cancers at a curable stage. All the seven cancers were detected by breast PET imaging, but only five of these were detected by whole-body PET imaging; the other two were detected by breast PET imaging using the breast positioning device. Conclusions In cancer screening, prone breast imaging using a positioning device may help to improve the detection rate of breast cancer. However, overall cancer including mammography and ultrasonography screening should be performed to investigate the false-negative cases and reduce false-positive cases. The effectiveness of prone breast PET imaging in cancer screening should be investigated using a much larger number of cases in the near future.     

Detection of colorectal cancer by routine ultrasound

In 95 consecutive patients with proven colonic carcinoma, the tumor was detected by routine sonography in only half of the patients. However, in 22 out of 23 tumors of the right colon, a correct diagnosis was suggested by sonography (sensitivity 95.5%). Although not suitable as a first choice screening procedure for colorectal cancer, routine abdominal ultrasound can detect even non-suspected colonic tumors, especially in the ascending colon. Since the specificity of ultrasound is probably low, diagnosis must be confirmed by X-ray and/or endoscopy.     

Medical radiologic technologist review: effects on a population-based breast cancer screening program

PURPOSE: To evaluate the effects of medical radiologic technologist review of mammograms in a population-based breast cancer screening program. MATERIALS AND METHODS: A technologist review pilot project was incorporated into the Regina, Saskatchewan, Canada, reading center. Technologists received special training in mammographic interpretation. They reviewed all 27,863 mammograms obtained at the center from July 1995 to September 1996 that were reviewed by a radiologist and selected cases for second blind reading by another radiologist. When the two radiologists' readings were in agreement, the report was sent. When the readings differed, a third opinion was obtained from the program's consulting radiologist. Changes in the number of mammograms interpreted as abnormal and the number of cancers detected were assessed. RESULTS: The technologist review was responsible for the detection of nine cancers missed at the first radiologist's interpretation. Technologists were very discriminating; only 391 cases (1.4%) were sent for double reading. The positive predictive value of screening did not change significantly (7.5% without review, 8.1% with review; P > .20). CONCLUSION: A substantial number of cancers were found with the technologist review. The number of mammograms interpreted as abnormal was reduced slightly. The technologist review proved to be a cost-effective alternative to double reading by two radiologists.     

FDG-PET improves the staging and selection of patients with recurrent colorectal cancer

Whole-body fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) has proved effective in the diagnosis and staging of recurrent colorectal cancer. In this study, we analysed how PET affects the management of patients with recurrent colorectal cancer by permitting more accurate selection of candidates for curative resection. The data of 79 patients with known or suspected recurrent colorectal cancer were analysed. Conventional imaging modalities (CIM) and PET results were compared with regard to their accuracy in determining the extent and the resectability of tumour recurrence. Recurrence was demonstrated in 68 of the 79 patients. The data indicate that PET was superior to CIM for detection of recurrence at all sites except the liver. Based on the CIM+PET staging, surgery with curative intent was proposed in 39 patients and was indeed achieved in 31 of them (80%). PET was more accurate than CIM alone in predicting the resectability or non-resectability of the recurrence (82% vs 68%, P=0.02). It is concluded that whole-body FDG-PET is highly sensitive for both the diagnosis and the staging of patients with recurrent colorectal cancer. Its use in conjunction with conventional imaging procedures results in a more accurate selection of patients for surgical treatment with curative intent.     

The impact of FDG-PET on the management algorithm for recurrent colorectal cancer.

Positron emission tomography (PET) has been successfully used to image colorectal cancer (CRC). This study evaluated the accuracy of 2-[(18)F]-fluoro-2-deoxy- D-glucose (FDG) PET for the detection and staging of recurrent CRC and the consequent impact on clinical management. Forty-two patients previously treated for CRC were investigated for suspected recurrence and, if recurrence was confirmed, the extent of disease was evaluated. All patients underwent whole-body FDG-PET and computed tomography (CT) scan and results were compared to assess sensitivity, specificity and diagnostic accuracy for each modality. We then assessed the FDG-PET directed alteration in clinical management from that planned on the basis of spiral CT results. FDG-PET was more sensitive (93%) than CT (73%) for detection of recurrence (specificity 58% and 75%, respectively). FDG-PET yielded a correct diagnosis in 35 (83%) out of 42 patients, while CT did so in 31 patients (74%). FDG-PET was more accurate than CT for staging local recurrence (sensitivity 100%, specificity 86% with FDG-PET vs 75% and 100%, respectively, with CT) and CRC liver metastases (sensitivity 100% vs 45%; specificity 100% for both). Overall, PET upstaged 8 out of 30 patients (27%) and altered patient management in 16 (38%) cases. This study confirms that FDG-PET is more sensitive than CT for the detection and staging of recurrent CRC. The results also indicate that FDG-PET is an accurate means of selecting appropriate patients for operative treatment. When applied to routine clinical practice, patient management is altered.     

Business administration of PET facilities: a nationwide survey for prices of PET screening and a cost analysis of three facilities

The purpose of this study is to analyze the business administration of PET facilities based on the survey of the price of PET cancer screening and cost analysis of PET examination. The questionnaire survey of the price of PET cancer screening was implemented for all PET facilities in Japan. Cost data of PET examination, including fixed costs and variable costs, were obtained from three different medical institutions. The marked price of the PET cancer screening was 111,499 yen in average, and the most popular range of prices was between 80,000 yen and 90,000 yen. Costs of PET per examination were accounted for 110,675 yen, 79,158 yen and Y11,644 yen in facility A, B and C, respectively. The results suggested that facilities with two or more PET/CT per a cyclotron could only secure profits. In Japan, the boom in PET facility construction could not continue in accordance with increasing number of PET facilities. It would become more essential to analyze the appropriate distribution of PET facilities and the adequate amount of PET procedures from the perspective of efficient utilization of the PET equipments and supply of PET-related healthcare.