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

Ultrathin colonoscopy can improve complete preoperative colonoscopy for stenotic colorectal cancer: Prospective observational study

OBJECTIVES

Preoperative colonoscopy is often incomplete for stenotic colorectal cancers (CRC). This prospective observational study aimed to evaluate the ability of an ultrathin colonoscope (UTC) to inspect the whole colon by passing through the stenotic CRC.

METHODS

All patients who underwent preoperative colonoscopy for stenotic CRCs at Shizuoka Cancer Center were examined for eligibility. If a standard colonoscope (PCF-H290ZI) could not pass because of a stenosis, the patients were recruited. All of the eligible patients were prospectively enrolled when informed consent could be obtained, and complete colonoscopy was attempted again using an UTC (PCF-PQ260L). Patients with stent placement and those requiring right hemicolectomy were not recruited. Primary endpoints were pass-through and cecal intubation rates. The detected synchronous neoplasias (adenomas and cancers) and their pathological findings after resection were evaluated.

RESULTS

A total of 100 patients were enrolled between September 2017 and February 2019. The mean age was 65.6 ± 10.8 years, and 59% were male. The pass-through and cecal intubation rates were 67% (67/100) and 58% (58/100), respectively. Synchronous lesions located proximal to the stenoses were detected in 65.5% (38/58) of the complete colonoscopies, with a total of 86 lesions, including 18 advanced neoplasias with three invasive cancers.

CONCLUSION

When standard colonoscopy cannot pass through stenotic CRC, ultrathin colonoscopy can be considered as an option to inspect the whole colon proximal to the stenosis because treatment strategy can potentially be changed by detecting synchronous neoplasias proximal to the stenosis before surgery. (UMIN000028505).

Ten-year prospective evaluation of whole-body cancer screening with multiple modalities including [18F]fluorodeoxyglucose positron emission tomography in a healthy population

PURPOSE

To prospectively evaluate the value of whole-body cancer screening with multiple modalities including FDG-PET in a healthy population.

METHODS

The study was conducted in 1197 healthy individuals aged ≥ 35 years at enrollment between August 2003 and July 2004. All participants were scheduled to receive annual whole-body cancer screening five times (screening period) with subsequent long-term follow-up (follow-up period). The endpoints of the study were definitive cancer diagnosis, cancer-related death, and all-cause death.

RESULTS

The follow-up rate was 99.8% for the screening period and 96.2% for the follow-up period. Forty-five cancers were confirmed during the screening period (August 2003 to July 2009), and 37 of the 45 were detected by the screening. Fourteen of the 45 were PET positive. Sixteen, 5, 4, 9 and 11 cancers were confirmed after the first, the second, the third, the fourth, and the fifth (took 2 years) screening, respectively. Eight participants died, of whom five died of cancer. The rate of cancer incidence (per 100,000) of 628.7 (95% confidence interval [CI] 445.0-812.4) was significantly high, and the rates of cancer mortality and all-cause mortality of 69.9 (95% CI 8.6-131.1) and 111.8 (95% CI 34.3-189.2), respectively, were significantly low, compared with the corresponding rates of 379.3, 138.2 and 354.2, respectively, in the age-rank- and sex-matched general population. During the follow-up period (August 2009 to July 2013), 37 cancers were confirmed and 30 of the 37 were detected. Seven participants died, of whom three died of cancer. The rate of cancer incidence was 809.6 (95% CI 548.7-1070.5). The rates of cancer mortality and all-cause mortality of 65.6 (95% CI 0-139.9) and 153.2 (95% CI 39.7-266.6), respectively, were significantly low compared with 190.1 and 462.3, respectively, in the general population.

CONCLUSION

Cancer detection by PET alone was limited. While the high cancer incidence was attributed to the extensive screening, the low cancer and all-cause mortality may indicate the potential value of this type of cancer screening. Cancer incidence increases with aging and it has been shown that continuous screening may reduce the risk caused by the cancer progression.

Usefulness of both PET/CT with F18-FDG and whole-body diffusion-weighted imaging in cancer screening: a preliminary report

OBJECTIVE

Positron emission tomography/computed tomography (PET/CT) with fluorodeoxyglucose (F18-FDG) is useful for the detection of malignant lesions, including metastatic lesions, and this technique is widely used in cancer screening. However, this approach may occasionally yield false-positive and false-negative findings. At our PET center, to increase the accuracy of PET/CT, we use PET/CT and whole-body diffusion-weighted imaging (WB-DWI) together. This study aimed to assess the usefulness of this combination.

METHODS

We examined 29 subjects with confirmed diagnosis. All of them had undergone PET/CT and WB-DWI on the same day. Twenty-seven of them also underwent ultrasonography, blood testing, and upper gastrointestinal series on the same day and two fecal occult blood tests on another day. WB-DWI was performed on a 1.5-T MRI unit with a b value of 0 and 800 or 1000 s/mm². For all 29 cases, PET/CT and WB-DWI were classified to be positive or negative, and the diagnostic ability was calculated for each modality.

RESULTS

Among the 29 subjects, 17 had malignant tumors and 12 had benign tumors or no abnormalities. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of PET/CT were 65%, 25%, 55%, 33%, and 48%, respectively; while the corresponding values for WB-DWI were 59%, 100%, 100%, 63%, and 76%, respectively. By considering the result to be negative when PET/CT findings were positive but WB-DWI findings were negative, specificity increased from 25 to 100%, and accuracy increased from 48 to 76%. On the other hand, by considering the result to be positive when the findings of either PET/CT or WB-DWI were positive, sensitivity increased from 65 to 76%, and accuracy increased from 48 to 55%.

CONCLUSIONS

Our results suggest that using both PET/CT and WB-DWI together can increase accuracy in cancer screening. However, this approach was not able to detect malignant lesions in some cases, indicating that there were limitations with imaging certain organs. Therefore, it is important to further understand the features of PET/CT and WB-DWI and use them appropriately for each organ. Additionally, given that the study sample was relatively small, further research is needed to validate these findings.

Triple primary cancer of the head and neck, skin and prostate: A case report and literature review

Second primary cancer (SPC) is an important prognostic factor for patients with head and neck cancer (HNC); therefore, the association between the prognosis and development of SPC has been well-reported. The use of 2-[18F]-fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET) is valuable to examine cancer stage, evaluate treatment responses and investigate suspected relapses or metastases. In the present study, the case of a male patient who was diagnosed with three primary cancer types, including well to moderately differentiated squamous cell carcinoma (SCC) of the mandible, axillary cutaneous poorly differentiated SCC and prostate adenocarcinoma, was described. Among these, mandible cancer was the first diagnosed when the patient was 70 years of age. Synchronous skin and prostate cancer (PRC) types then developed 3 years later. To the best of our knowledge, this is the first report of the aforementioned combination of cancer types. Postoperative FDG-PET was not performed as no lesions of recurrence or metastases of mandible cancer were found. Three years later, the PRC was asymptomatic and was incidentally detected by FDG-PET performed for a preoperative evaluation of skin cancer. It was indicated that FDG-PET could be utilized in patients with HNC due to there being no accurate FDG-PET protocol to detect SPC over a long-term follow-up.

Can positron emission tomography detect colorectal adenomas and cancers?

BACKGROUND AND AIM

Fluorine-18 2-fluoro-2-deoxy-d-glucose positron emission tomography (PET) is effective and less invasive than other modalities used to diagnose tumors, including colorectal cancer (CRC). However, the detectability of adenomas and CRCs, especially in the early stages, is unclear.

METHODS

We evaluated the records of 2323 consecutive eligible patients who underwent both a total colonoscopy (TCS) and PET between October 2002 and September 2012 at a tertiary cancer center. The PET findings were verified by TCS performed independently within 1 year. Target lesions were defined as CRCs and adenomas that were 6 mm or larger in size.

RESULTS

Total colonoscopy detected 532 target lesions ≥ 6 mm in size: 56 T2-T4 CRCs, 39 T1 CRCs, 223 advanced adenomas, and 214 low-grade adenomas. Of the 532 lesions, 216 (40.6%) were PET positive. Of the 369 cases with positive uptakes, PET detected target lesions in the matched segments for 58.5% (216/369). Sensitivity of PET to T2-T4 CRCs, T1 CRCs, advanced adenomas, and low-grade adenomas was 92.9%, 79.5%, 50.7%, and 9.3%, respectively. PET could detect 76.5% (13/17) of T1 CRCs whose size is 10 to 19 mm and 85.0% (17/20) of T1 CRCs equal or larger than 20 mm. The multivariate analysis excluding T2-T4 CRCs showed malignant histology, larger size, protruded lesions, villous histology, and lesions in distal colon were significant factors.

CONCLUSIONS

Sensitivity of PET for detecting T2-T4 and even T1 cancers are promising. However, sensitivity of PET to adenomas, even advanced adenomas, is limited.

Systematic Review on the Accuracy of Positron Emission Tomography/Computed Tomography and Positron Emission Tomography/Magnetic Resonance Imaging in the Management of Ovarian Cancer: Is Functional Information Really Needed?

Ovarian cancer (OC) often presents at an advanced stage with frequent relapses despite optimal treatment; thus, accurate staging and restaging are required for improving treatment outcomes and prognostication. Conventionally, staging of OC is performed using contrast-enhanced computed tomography (CT). Nevertheless, recent advances in the field of hybrid imaging have made positron emission tomography/CT (PET/CT) and PET/magnetic resonance imaging (PET/MRI) as emerging potential noninvasive imaging tools for improved management of OC. Several studies have championed the role of PET/CT for the detection of recurrence and prognostication of OC. We provide a systematic review and meta-analysis of the latest publications regarding the role of molecular imaging in the management of OC. We retrieved 57 original research articles with one article having overlap in both diagnosis and staging; 10 articles (734 patients) regarding the role of PET/CT in diagnosis of OC; 12 articles (604 patients) regarding staging of OC; 22 studies (1429 patients) for detection of recurrence; and 13 articles for prognostication and assessment of treatment response. We calculated pooled sensitivity and specificity of PET/CT performance in various aspects of imaging of OC. We also discussed the emerging role of PET/MRI in the management of OC. We aim to give the readers and objective overview on the role of molecular imaging in the management of OC.

A preliminary report of breast cancer screening by positron emission mammography

OBJECTIVE

Fluorine-18 fluorodeoxyglucose (FDG)-positron emission tomography (PET) and PET/computed tomography (PET/CT) have had a considerable impact on the detection of various malignancies. PET and PET/CT are minimally invasive methods that can provide whole-body imaging at one time. Therefore, an FDG-PET cancer screening program has been widely used in Japan. However, the breast cancer detection rate of FDG-PET cancer screening is relatively low. Therefore, FDG-PET screening is not recommended for breast cancer screening. Positron emission mammography (PEM) is a high-resolution molecular breast imaging technology. PEM can detect small breast cancers that cannot be detected on PET or PET/CT images due to limited spatial resolution. We have performed opportunistic breast cancer screening using PEM since 2011. To the best of our knowledge, this is the first report regarding PEM breast cancer screening.

METHODS

This study enrolled 265 women. PEM images were analyzed by agreement of 2 experienced nuclear medicine physicians. The readers were given information from medical interview sheet. US findings were interpreted holistically. The number of participants, patient recall rate, further examination rate, and cancer detection rate by year were calculated.

RESULTS

The overall recall rate was 8.3%; the work-up examination rate was 77.3%, and cancer detection rate was 2.3%. The positive predictive value of PEM was 27.3%. Six cancers were found by PEM screening. Five were invasive cancers and one was ductal carcinoma in situ. Histological tumor sizes were reported in three cases: 0.7, 1.2, and 2 cm.

CONCLUSION

PEM screening appears to have potential for breast cancer screening.

Quantitative Analysis of Torso FDG-PET Scans by Using Anatomical Standardization of Normal Cases from Thorough Physical Examinations

Understanding of standardized uptake value (SUV) of 2-deoxy-2-[18F]fluoro-d-glucose positron emission tomography (FDG-PET) depends on the background accumulations of glucose because the SUV often varies the status of patients. The purpose of this study was to develop a new method for quantitative analysis of SUV of FDG-PET scan images. The method included an anatomical standardization and a statistical comparison with normal cases by using Z-score that are often used in SPM or 3D-SSP approach for brain function analysis. Our scheme consisted of two approaches, which included the construction of a normal model and the determination of the SUV scores as Z-score index for measuring the abnormality of an FDG-PET scan image. To construct the normal torso model, all of the normal images were registered into one shape, which indicated the normal range of SUV at all voxels. The image deformation process consisted of a whole body rigid registration of shoulder to bladder region and liver registration and a non-linear registration of body surface by using the thin-plate spline technique. In order to validate usefulness of our method, we segment suspicious regions on FDG-PET images manually, and obtained the Z-scores of the regions based on the corresponding voxels that stores the mean and the standard deviations from the normal model. We collected 243 (143 males and 100 females) normal cases to construct the normal model. We also extracted 432 abnormal spots from 63 abnormal cases (73 cancer lesions) to validate the Z-scores. The Z-scores of 417 out of 432 abnormal spots were higher than 2.0, which statistically indicated the severity of the spots. In conclusions, the Z-scores obtained by our computerized scheme with anatomical standardization of torso region would be useful for visualization and detection of subtle lesions on FDG-PET scan images even when the SUV may not clearly show an abnormality.

Detection of colorectal cancer and adenomas by FDG-PET cancer screening program: results based on a nationwide Japanese survey

PURPOSE

The aim of this study was to analyze the detection rate for CRC and adenomas for asymptomatic subjects in Japan by FDG-PET cancer screening program carried out between 2006 and 2009.

METHODS

The "FDG-PET cancer screening program" included both PET and positron emission tomography with computed tomography (PET/CT) with or without other screening tests. A total of 154,783 asymptomatic subjects underwent FDG-PET cancer screening program; we analyzed the 1,808 cases with findings from any detection method that indicated suspected CRC.

RESULTS

Among the 1,808 cases, the number of cases verified as CRC and adenoma was 394 and 679, respectively. The sensitivity and positive predictive value (PPV) of FDG-PET were 86.0 and 31.7% for CRC, and 63.6 and 63.8% for CRC and adenoma. The sensitivity and PPV of fecal occult blood test (FOBT) for CRC were lower than those of FDG-PET, but higher for adenoma. Therefore, FDG-PET and FOBT were complementary for screening for CRC, and CRC and adenoma. The majority of CRC detected by the FDG-PET imaging was UICC stage 0 or I, however, detection of smaller or less invasive cancer was limited.

CONCLUSION

The FDG-PET screening program in Japan has detected CRC at an early stage and adenomas as premalignant lesions. A combination of FDG-PET and FOBT yields the best results if the intent is to detect either CRC or adenoma. However, it is absolutely clear that an FDG-PET cancer screening program cannot detect all colon lesions.

Assessment of (18)F-fluorodeoxyglucose positron emission tomography combined with computed tomography in the preoperative management of patients with gastric cancer

BACKGROUND

The significance of (18)F-2-deoxy-2-fluoro-glucose positron emission tomography combined with computed tomography imaging (FDG-PET/CT) in the diagnosis of gastric cancer remains controversial. This study aimed to evaluate the efficacy of preoperative FDG-PET/CT in staging of gastric cancer.

METHODS

FDG-PET/CT results for 90 patients with gastric cancer were retrospectively examined. For quantitative PET analysis, FDG uptake was assessed based on the maximum standardized uptake values (SUVmax).

RESULTS

FDG-PET/CT detected the primary gastric cancer in 71 of the 90 patients (sensitivity 78.9 %). The median SUVmax was significantly higher in patients with T3/T4 disease than in those with T1/T2 (9.0 vs. 3.8; P < 0.001), in patients with distant metastasis than in those with no metastasis (9.5 vs. 7.7; P = 0.018), and with stage III/IV tumors than in those with stage I/II (9.0 vs. 4.7; P = 0.017). The SUVmax of the primary tumor was significantly correlated with tumor size (r = 0.461, P < 0.001). The sensitivity, specificity, and accuracy of FDG-PET/CT in assessing metastasis to regional lymph nodes were 64.5, 85.7, and 71.1 %, respectively.

CONCLUSIONS

FDG-PET/CT results are significantly associated with tumor progression in gastric cancer, and such findings can reliably identify cancer cell populations.

Patient with esophageal cancer showing remission of nephrotic syndrome after esophagectomy: report of a case

A 73-year-old male patient was admitted to our hospital due to bilateral leg edema and proteinuria in April 2009. After admission, nephrotic syndrome (membranous nephropathy) was diagnosed. At that point, a cancer screening test was performed; however, no abnormalities were noted. Medical treatment with prednisolone and cyclosporine was started, which resulted in the temporary improvement of markers of laboratory data. The patient was re-examined in November of the same year, and esophageal cancer (squamous cell carcinoma, T2N0M0 Stage IIA according to the UICC TNM classification) was detected in the lower thoracic esophagus. Subtotal esophagectomy was performed via right thoracolaparotomy with two-field lymph node dissection. Although the patient's course was complicated by respiratory failure, he was discharged after 38 days. After performing esophagectomy, prompt amelioration of the nephrotic syndrome occurred, allowing the withdrawal of prednisolone and cyclosporine. There has been no recurrence of esophageal cancer or relapse of nephrotic syndrome during a period of 18 months after esophagectomy.

The current status of an FDG-PET cancer screening program in Japan, based on a 4-year (2006-2009) nationwide survey

Objective

The aim of this study was to survey the 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) cancer screening program conducted in Japan.

Methods

The “FDG-PET cancer screening program” included both FDG-PET and positron emission tomography with computed tomography (PET/CT) with or without other combined screening tests that were performed for cancer screening in asymptomatic subjects. A total of 155,456 subjects who underwent the FDG-PET cancer screening program during 2006–2009 were analyzed.

Results

Of the 155,456 subjects, positive findings suggesting possible cancer were noted in 16,955 (10.9 %). The number of cases with detected cancer was 1,912 (1.23 % of the total screened cases, annual range 1.14–1.30 %). Of the 1,912 cases of detected cancer, positive findings on FDG-PET were present in 1,491 cases (0.96 % of the total number of screened cases). According to the results of further examinations, the true positive rate for subjects with suggested possible cancer (positive predictive value) was 32.3 % with FDG-PET. Cancers of the colon/rectum, thyroid, lung, and breast were most frequently found (396, 353, 319, and 163 cases, respectively) with high PET sensitivity (85.9, 90.7, 86.8, 84.0 %, respectively). Prostate cancer and gastric cancer (165 and 124 cases, respectively) had low PET sensitivity (37.0 and 37.9 %, respectively). The Union for International Cancer Control (UICC) clinical stage of cancer found with the FDG-PET cancer screening program was mainly Stage I.

Conclusions

The FDG-PET screening program in Japan has detected a variety of cancers at an early stage. However, several cancers were found in repeated FDG-PET cancer screening program, indicating the limitation of a one-time FDG-PET cancer screening program. The value of the FDG-PET cancer screening program is left to the judgment of individuals with regard to its potentials and limitations.

Imaging of female pelvic malignancies regarding MRI, CT, and PET/CT: Part 2

PURPOSE

To compose diagnostic standard operating procedures for both clinical and imaging assessment for vulvar and vaginal cancer, for vaginal sarcoma, and for ovarian cancer.

METHODS

The literature was reviewed for diagnosing the above mentioned malignancies in the female pelvis. Special focus herein lies in tumor representation in MRI, followed by the evaluation of CT and PET/CT for this topic.

CONCLUSION

MRI is a useful additional diagnostic complement but by no means replaces established methods of gynecologic diagnostics and ultrasound. In fact, MRI is only implemented in the guidelines for vulvar cancer. According to the current literature, CT is still the cross-sectional imaging modality of choice for evaluating ovarian cancer. PET/CT appears to have advantages for staging and follow-up in sarcomas and cancers of the ovaries.

GLUT1 expression in malignant tumors and its use as an immunodiagnostic marker

OBJECTIVE

To analyze glucose transporter 1 expression patterns in malignant tumors of various cell types and evaluate their diagnostic value by immunohistochemistry.

INTRODUCTION

Glucose is the major source of energy for cells, and glucose transporter 1 is the most common glucose transporter in humans. Glucose transporter 1 is aberrantly expressed in several tumor types. Studies have implicated glucose transporter 1 expression as a prognostic and diagnostic marker in tumors, primarily in conjunction with positron emission tomography scan data.

METHODS

Immunohistochemistry for glucose transporter 1 was performed in tissue microarray slides, comprising 1955 samples of malignant neoplasm from different cell types.

RESULTS

Sarcomas, lymphomas, melanomas and hepatoblastomas did not express glucose transporter 1. Forty-seven per cent of prostate adenocarcinomas were positive, as were 29% of thyroid, 10% of gastric and 5% of breast adenocarcinomas. Thirty-six per cent of squamous cell carcinomas of the head and neck were positive, as were 42% of uterine cervix squamous cell carcinomas. Glioblastomas and retinoblastomas showed membranous glucose transporter 1 staining in 18.6% and 9.4% of all cases, respectively. Squamous cell carcinomas displayed membranous expression, whereas adenocarcinomas showed cytoplasmic glucose transporter 1 expression.

CONCLUSION

Glucose transporter 1 showed variable expression in various tumor types. Its absence in sarcomas, melanomas, hepatoblastomas and lymphomas suggests that other glucose transporters mediate the glycolytic pathway in these tumors. The data suggest that glucose transporter 1 is a valuable immunohistochemical marker that can be used to identify patients for evaluation by positron emission tomography scan. The function of cytoplasmic glucose transporter 1 in adenocarcinomas must be further examined.