carbon-11-acetate and Adenocarcinoma

Patients with rising prostate-specific antigen (PSA) levels after definitive local therapy of prostate carcinoma present a diagnostic dilemma. A local recurrence would be amenable to additional local therapy with curative intent, whereas metastatic disease would require palliative androgen ablation therapy. In this study, we evaluated the effectiveness of PET with (11)C-acetate (AC PET) for evaluation of patients with rising PSA after radical prostatectomy or radiation therapy. We also compared the reliability of AC PET in detecting recurrent prostate cancer with that of PET with (18)F-FDG.. Two groups of patients with PSA recurrence were enrolled in this study: group A, 30 patients after prostatectomy, and group B, 16 patients after radiation therapy. After administration of 1,110 MBq (30 mCi) of (11)C-acetate, whole-body PET images were obtained. After allowing for (11)C decay, 555 MBq (15 mCi) of (18)F-FDG were administered and repeated whole-body imaging was performed. The PET findings were scored as positive or negative in each of the following regions: prostatic bed, pelvic nodes, paraaortic nodes, and other sites (bone or soft tissue). PET findings were correlated with those of CT, bone scintigraphy, and biopsy.. Twenty-seven of 46 AC PET studies (59%) had positive findings, whereas only 8 (18)F-FDG PET studies had positive findings (17%). Limiting the analysis to patients with findings confirmed by CT, bone scintigraphy, or biopsy or considered highly likely to represent tumor, 14 (30%) had disease identified by AC PET, whereas only 4 (9%) had disease identified by (18)F-FDG PET. CT was performed on 22 patients and had positive findings in 3 (14%). Thirteen of 22 patients (59%) with serum PSA > 3 ng/mL had positive AC PET findings, whereas only 1 of 24 patients (4%) with serum PSA levels < or = 3 ng/mL had positive findings.. AC PET demonstrates marked uptake in prostate cancer and has higher sensitivity than (18)F-FDG PET. These preliminary data show that (11)C-acetate is a promising tracer for detection of recurrent prostate cancer.

Topics: Acetates; Adenocarcinoma; Aged; Carbon; Fluorodeoxyglucose F18; Humans; Male; Middle Aged; Neoplasm Recurrence, Local; Prostate-Specific Antigen; Prostatectomy; Prostatic Neoplasms; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Single-Blind Method; Tomography, Emission-Computed

Carbon-11 acetate positron emission tomography (PET) has been reported to be of clinical value for the diagnosis of prostate cancer. However, no detailed analysis has yet been carried out on the physiological accumulation of [(11)C]acetate in the prostate. The purpose of this study was to elucidate the physiological accumulation of [(11)C]acetate in the prostate using dynamic PET. The study included 30 subjects without prostate cancer [21 with normal prostate and nine with benign prostatic hyperplasia (BPH)] and six patients with prostate cancer. A dynamic PET study was performed for 20 min after intravenous administration of 555 MBq of [(11)C]acetate. The standardised uptake value (SUV) at 16-20 min post tracer administration and the early-to-late-activity ratio of the SUV (E/L ratio), which was determined by dividing the SUV(6-10 min) by the SUV(16-20min), were calculated to evaluate the accumulation of [(11)C]acetate. The prostate was clearly visualised and distinguished from adjacent organs in PET images in most of the cases. The SUV of the prostate (2.6+/-0.8) was significantly higher than that of the rectum (1.7+/-0.4) or bone marrow (1.3+/-0.3) ( P<0.0001 in each case). The SUV of the normal prostate of subjects aged <50 years (3.4+/-0.7) was significantly higher than both the SUV for the normal prostate of subjects aged > or =50 years (2.3+/-0.7) and that of subjects with BPH (2.1+/-0.6) ( P<0.01 in each case). The primary prostate cancer in six cases was visualised by [(11)C]acetate PET. However, the difference in the SUV between subjects aged > or =50 with normal prostate or with BPH and the patients with prostate cancer (1.9+/-0.6) was not statistically significant. There was also no significant difference in the E/L ratio between subjects aged > or =50 with normal prostate (0.98+/-0.04) or BPH (0.96+/-0.08) and patients with prostate cancer (1.02+/-0.12). In conclusion, a normal prostate exhibits age-related physiological accumulation of [(11)C]acetate. Careful interpretation of [(11)C]acetate PET images of prostate cancer is necessary because the SUV and the E/L ratio for the normal prostate and for BPH overlap significantly with those for prostate cancer.

Topics: Acetates; Adenocarcinoma; Adult; Age Factors; Aged; Aged, 80 and over; Carbon; Diagnosis, Differential; Humans; Male; Middle Aged; Neoplasms; Organ Specificity; Prostate; Prostatic Hyperplasia; Prostatic Neoplasms; Radiopharmaceuticals; Tomography, Emission-Computed

11C-Acetate can act as a probe of tissue metabolism through entry into catabolic or anabolic metabolic pathways as mediated by acetyl-coenzyme A. The uptake of (11)C-acetate in prostate cancer was investigated to determine whether this tracer has potential in tumor identification.. Twenty-two patients with prostate cancer underwent PET after intravenous administration of 740 MBq (11)C-acetate. Eighteen of the 22 patients were also investigated with (18)F-FDG PET. Standardized uptake values (SUVs) for each tumor were investigated for tracer activity at 10-20 min after (11)C-acetate and 40-60 min after (18)F-FDG administration.. Adenocarcinoma of the prostate showed variable uptake of (11)C-acetate, with SUVs ranging from 3.27 to 9.87. In contrast, SUVs for (18)F-FDG ranged from 1.97 to 6.34. By visual inspection, (11)C-acetate accumulation in primary prostate tumors was positive in all patients, whereas (18)F-FDG accumulation was positive in only 15 of 18 patients. (11)C-Acetate PET in a patient with lymph node metastasis showed high intrapelvic accumulation corresponding to metastatic sites. Similarly, 2 patients with bone metastases were (11)C-acetate avid.. (11)C-Acetate shows marked uptake in prostate cancer and is more sensitive in detection of prostate cancer than is (18)F-FDG PET. (11)C-Acetate represents a new tracer for detection of prostate cancer with PET, measuring radiopharmaceutical uptake pathways that are different from those measured by (18)F-FDG.

Topics: Acetates; Adenocarcinoma; Aged; Aged, 80 and over; Bone Neoplasms; Carbon; Carbon Radioisotopes; Fluorodeoxyglucose F18; Humans; Lymph Nodes; Lymphatic Metastasis; Male; Middle Aged; Prostatic Neoplasms; Radiopharmaceuticals; Sensitivity and Specificity; Tomography, Emission-Computed

To determine the usefulness of positron emission tomography (PET) with (11)C-acetate (AC) for imaging lung adenocarcinoma and evaluating its tumor aggressiveness, AC- and (18)F-fluorodeoxyglucose (FDG)-PET were compared.. One hundred and sixty-nine adenocarcinomas with clinical stage IA and 53 benign nodules were examined by both AC- and FDG-PET before surgery. The sensitivity and specificity for discriminating benign/adenocarcinoma were compared between AC- and FDG-PET. The AC and FDG uptakes were examined to determine the relationship with tumor aggressiveness, i.e., pathological tumor stage, lymphatic, vascular, or pleural involvement, and proliferative activity determined by Ki-67 staining score.. While the sensitivity of AC-PET was significantly higher than FDG-PET for bronchioloalveolar carcinoma (BAC) and well-differentiated (W/D) adenocarcinoma (p < 0.001 and 0.006, respectively), there was no significant difference for moderately or poorly differentiated adenocarcinoma. The specificity was not different between them. While FDG uptakes were significantly higher in tumors with pathological advanced stages or those with lymphatic, vascular and/or pleural involvements than in tumors with pathological stage IA or those without these tumor involvements (p = 0.04 to p < 0.001), AC uptake did not show significant differences between the respective sub-groups except according to the tumor stage. While both AC and FDG uptakes showed a significant correlation with Ki-67 staining scores (p = 0.03 and p < 0.001, respectively), the correlation coefficient of former was lower than that of latter (p = 0.07).. While AC-PET can image BAC and W/D adenocarcinoma with a higher sensitivity than FDG-PET, it cannot evaluate tumor aggressiveness of clinical stage IA lung adenocarcinoma as well as FDG-PET.

Topics: Acetates; Adenocarcinoma; Carbon; Fluorodeoxyglucose F18; Humans; Lung Neoplasms; Neoplasm Staging; Positron-Emission Tomography; ROC Curve; Tomography, X-Ray Computed; Tumor Burden

Pancreatic carcinoma is a malignant tumor with poor prognosis and its early detection is still a clinical problem. The aim of this study was to evaluate the efficacy of carbon-11-labeled acetate (11C-acetate)-positron emission tomography (PET) for the detection of pancreatic carcinoma in a BxPC-3 human pancreatic carcinoma xenograft-bearing immunodeficiency BALB/c-nu nude mice model.. Whole-body 11C-acetate and fluorine-18-labeled fluorodeoxyglucose (F-FDG) micro-PET imaging were performed weekly on BxPC-3 human pancreatic carcinoma xenograft-bearing BALB/c-nu nude mice from the 2nd week after tumor cell inoculation. Regions of interest method and tumor-to-nontumor ratio (T/N ratio) were used for semiquantitative evaluation. Tumor proliferation was evaluated by immunohistochemistry analysis of proliferating cell nuclear antigen.. Radiotracer accumulation in the tumor xenografts could be detected 1 week earlier in 11C-acetate-PET than that in 18F-FDG-PET. Peak T/N ratio was obtained at the 5th week in 11C-acetate-PET and at the 4th week in 18F-FDG-PET. T/N ratio in 11C-acetate-PET was lower than that in 18F-FDG-PET during the same period. By visual evaluation, tumor xenografts were more easily observed in 11C-acetate-PET than in 18F-FDG-PET in most of the mice. Linear correlation analysis indicated T/N ratios in C-acetate-PET had no significant correlation with those in 18F-FDG-PET. Tumor size, T/N ratio in 11C-acetate-PET, and T/N ratio in 18F-FDG-PET were not found to be significantly correlated with tumor proliferating cell nuclear antigen expression.. 11C-acetate-PET imaging can be used for the detection of pancreatic carcinoma. In the early stage of tumor growth, 11C-acetate-PET has better detectability than that of 18F-FDG-PET.

Topics: Acetates; Adenocarcinoma; Animals; Carbon; Carbon Radioisotopes; Cell Line, Tumor; Fluorodeoxyglucose F18; Humans; Immunohistochemistry; Isotope Labeling; Male; Mice; Mice, Inbred BALB C; Neoplasm Transplantation; Pancreatic Neoplasms; Positron-Emission Tomography; Proliferating Cell Nuclear Antigen; Radiopharmaceuticals

Although positron emission tomography (PET) using F-fluorodeoxy-glucose (FDG) frequently gives false-negative results for slow-growing tumors, C-acetate (AC)-PET has been reported to be able to detect them. To determine the usefulness of AC-PET for imaging non-small cell lung cancers (NSCLCs), the sensitivity and specificity were compared between the AC-PET and FDG-PET with a multicenter study.. A total of 284 pulmonary lesions (227 NSCLCs and 57 benign lesions) were examined using both AC-PET and FDG-PET before surgery at seven Japanese institutes. The AC- or FDG-uptake in each lesion were quantitatively measured using the contrast ratio of the standard uptake value between the lesions and the contralateral lung.. The sensitivity of AC-PET for diagnosing NSCLC was 0.71, which was significantly higher than the value of 0.57 obtained by FDG-PET (p < 0.001). No significant difference in the specificity was seen between AC- and FDG-PET. For the 146 well-differentiated adenocarcinomas, the sensitivity of AC-PET was 0.62, which was significantly higher than the value of 0.37 obtained by FDG-PET (p < 0.001). Of the 51 moderately- or poorly-differentiated adenocarcinomas and 30 nonadenocarcinomas, there was no significant difference of sensitivity between AC- and FDG-PET.. AC-PET could be used in place of FDG-PET for imaging NSCLC, with higher sensitivity for well-differentiated adenocarcinoma compared with FDG-PET.

Topics: Acetates; Adenocarcinoma; Carbon; Carbon Radioisotopes; Carcinoma, Non-Small-Cell Lung; Carcinoma, Squamous Cell; Cell Differentiation; Fluorodeoxyglucose F18; Humans; Lung Neoplasms; Lymphatic Metastasis; Neoplasm Staging; Positron-Emission Tomography; Prospective Studies; Radiopharmaceuticals; Retrospective Studies; ROC Curve; Sensitivity and Specificity; Tomography, X-Ray Computed

Positron emission tomography (PET) with 11C-acetate has been recently reported in detection of slow-growing tumors, such as well-differentiated adenocarcinomas of the lung, which are often negative with 18F-fluorodeoxyglucose (FDG) PET. Here we present findings of acetate-PET and FDG-PET in a case of adenocarcinoma that was comprised of peripheral ground glass opacity and solid central components, and was histologically comprised of both a well-differentiated and a moderately-differentiated adenocarcinoma, respectively. Acetate-PET was positive in both components, whereas FDG-PET was only positive in the solid central component. The present case demonstrates the figurative findings of acetate-PET and FDG-PET in lung adenocarcinoma.

Topics: Acetates; Adenocarcinoma; Aged; Carbon; Carbon Radioisotopes; Female; Fluorodeoxyglucose F18; Humans; Lung Neoplasms; Positron-Emission Tomography

Positron-emission tomography (PET) with 18F-fluorodeoxy-glucose (FDG) frequently gives false-negative results for well-differentiated adenocarcinomas of the lung, especially, those with ground-glass opacity images. Recently, PET with 11C-acetate (AC) has been reported to detect slow-growing tumors that have failed to be identified by FDG-PET, such as well-differentiated hepatocellular carcinomas and prostate cancers. To determine the usefulness of AC-PET in detecting well-differentiated adenocarcinomas of the lung, we performed both AC-PET and FDG-PET on pulmonary nodules with ground-glass opacity images on computed tomography (CT).. Fifty-four pulmonary nodules 1 to 3 cm in size, which showed ground-glass opacity images over their whole or peripheral area on CT, were examined by both AC-PET and FDG-PET.. Thirty-seven nodules were adenocarcinoma of the lung, while 17 were inflammatory. Of the 37 adenocarcinomas, 19 (51%) were positively identified by AC-PET and 14 (38%) by FDG-PET. Of the 23 adenocarcinomas which were not identified by FDG-PET, 8 (35%) were positively identified by AC-PET; all were well-differentiated adenocarcinomas. Of the 17 inflammatory nodules, 8 were chronic and 9 were acute ones. While none of the 8 chronic inflammatory nodules were identified by either technique, 9 acute ones showed a variety of the results with AC- and FDG-PET.. AC-PET detected approximately one third of well-differentiated adenocarcinomas of the lung which were not identified by FDG-PET. AC-PET could be useful to diagnose pulmonary nodules with ground-glass opacity images which were not identified by FDG-PET.

Topics: Acetates; Adenocarcinoma; Carbon; Carbon Radioisotopes; Fluorodeoxyglucose F18; Humans; Lung Neoplasms; Positron-Emission Tomography; Radiopharmaceuticals; Tomography, X-Ray Computed