Sandro Sironi

Value of integrated PET/CT for lesion localisation in cancer patients: a comparative study

The aim of this study was to retrospectively compare the value of integrated PET/CT and separate PET plus morphological imaging studies for lesion localisation in cancer patients. Two different series of consecutive patients who had previously been treated for neoplastic disease were considered. One series consisted of 105 patients who had undergone [18F]fluorodeoxyglucose (FDG) PET/CT (n=70) or [11C]choline PET/CT (n=35) studies (PET/CT group). The other series comprised 105 patients who had undergone FDG PET scan (n=70) or [11C]choline PET scan (n=35) alone; in this series, PET findings were correlated with the results of morphological imaging (MI) studies, i.e. CT (n=92) or MR imaging (n=13) (PET+MI group). Regions of abnormal tracer uptake at PET scanning were classified as ambiguous or unambiguous depending on their precise anatomical localisation. A total of 207 and 196 lesions were found in the PET/CT and PET+MI groups, respectively. The difference in terms of number of lesions per patient detected with the two imaging protocols was not statistically significant (P=0.718). When analysis of lesion localisation was performed, there were 7/207 (3.4%) and 30/196 (15.3%) ambiguous lesions in the PET/CT and PET+MI groups, respectively. The number of ambiguous lesions was significantly higher in the PET+MI group than in the PET/CT group (χ2=15.768, P<0.0001). Comparison of the effect of use of the different tracers on reporting of PET/CT versus PET+MI revealed that the improvement in the final report in [11C]choline PET/CT studies was similar to that observed in [18F]FDG studies. In cancer patients, PET/CT shows higher diagnostic accuracy for lesion localisation than PET plus morphological imaging studies performed independently. This result does not seem to be affected by the type of tracer used.

Role of the integrated FDG PET/CT in the surgical management of patients with high risk clinical early stage endometrial cancer: Detection of pelvic nodal metastases

BACKGROUND High risk clinical stage I endometrial cancer (grade 2 and deep myometrial invasion, grade 3 and serous and clear-cell carcinoma) had 10-35% of nodal involvement. Surgical staging is considered reasonable in this setting of women, although unnecessary in 70-90%. The purpose of this study was to determine prospectively the diagnostic accuracy of 18F-fluorodeoxyglucose Positron Emission Tomography/Computed Tomography 18F-FDG PET/CT in the detection of nodal metastases in patients with high risk endometrial cancer. METHODS Eleven women with grade 2 and deep myometrial invasion and 26 with grade 3 endometrial cancer underwent 18F-FDG PET/CT, followed by total hysterectomy, bilateral salpingo-oophorectomy and systematic pelvic lymphadenectomy. Histopathological findings served as the reference standard. Diagnostic performance of 18F-FDG PET/CT in nodal disease detection was reported in terms of accuracy value both in a patient-based and a lesion site-based analysis. RESULTS Pelvic nodes metastases were found at histopathological analysis in 9 of the 37 patients (24.3%). Patient-based sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 18F-FDG PET/CT for detection of nodal disease were 77.8%, 100.0%, 100.0%, 93.1% and 94.4%, respectively. Nodal lesion site-based sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 18F-FDG PET/CT were 66.7%, 99.4%, 90.9%, 97.2% and 96.8%, respectively. CONCLUSION This study shows that 18F-FDG PET/CT is an accurate method for the presurgical evaluation of pelvic nodes metastases. The high negative predictive value may be useful in selecting patients who only may benefit from lymphadenectomy, minimizing operative and surgical complications.

Breast Cancer Liver Metastases: US-guided Percutaneous Radiofrequency Ablation—Intermediate and Long-term Survival Rates

PURPOSE To retrospectively assess the local control and intermediate- and long-term survival of patients with liver metastases from breast cancer who have undergone percutaneous ultrasonography (US)-guided radiofrequency (RF) ablation. MATERIALS AND METHODS This study was approved by the hospital ethics committee, and all patients provided written informed consent. RF ablation was used to treat 87 breast cancer liver metastases (mean diameter, 2.5 cm) in 52 female patients (median age, 55 years). Inclusion criteria were as follows: fewer than five tumors, maximum tumor diameter of 5 cm or smaller, and disease either confined to the liver or stable with medical therapy. Forty-five (90%) of 50 patients had previously undergone chemotherapy, hormonal therapy, or both, and had no response or an incomplete response to the treatment. Contrast material-enhanced computed tomography and US were performed to evaluate complications and technical success and to assess for local tumor progression during follow-up. The Kaplan-Meier method was used to assess survival, and results were compared between groups with a log-rank test. Cox regression analysis was used to assess independent prognostic factors that affected survival. RESULTS Complete tumor necrosis was achieved in 97% of tumors. Two (4%) minor complications occurred. Median time to follow-up from diagnosis of liver metastasis and from RF ablation was 37.2 and 19.1 months, respectively. Local tumor progression occurred in 25% of patients. New intrahepatic metastases developed in 53% of patients. From the time of first RF ablation, overall median survival time and 5-year survival rate were 29.9 months and 27%, respectively. From the time the first liver metastasis was diagnosed, overall median survival time was 42 months, and the 5-year survival rate was 32%. Patients with tumors 2.5 cm in diameter or larger had a worse prognosis (hazard ratio, 2.1) than did patients with tumors smaller than 2.5 cm in diameter. CONCLUSION Survival rates in selected patients with breast cancer liver metastases treated with RF ablation are comparable to those reported in the literature that were achieved with surgery or laser ablation.

Hepatocellular carcinoma in cirrhotic liver disease: functional computed tomography with perfusion imaging in the assessment of tumor vascularization

RATIONALE AND OBJECTIVES Our goal was to prospectively determine the value of perfusion computed tomography (CT) in the quantitative assessment of tumor-related angiogenesis in cirrhotic patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS Forty-seven patients met all the following inclusion criteria: 1) Child-Pugh class A or B liver cirrhosis; 2) presence of a single lesion suspected as HCC at screening ultrasound examination; and 3) lesion diameter between 1 and 3 cm. All patients underwent contrast-enhanced ultrasound, pre- and post-contrast triple-phase CT, and perfusion computed tomographic study using multidetector 16-slice CT. Six parameters related to the blood microcirculation and tissue perfusion were measured for the focal liver lesion and cirrhotic parenchyma: perfusion (P), tissue blood volume (BV), hepatic perfusion index (HPI), arterial perfusion (AP), portal perfusion (PP), and time to peak (TTP). Perfusion parameters were described with quartile values of their distribution; univariate paired and unpaired Wilcoxon signed rank tests were used for statistical analysis. RESULTS HCC was diagnosed in 21 of the 47 patients; in the remaining 26, HCC was not found at contrast-enhanced ultrasound and multidetector 16-slice computed tomographic study. The values of perfusion parameters measured within tumor tissue were: P (ml/s/100 g): median = 47.0 (first quartile = 36.0, third quartile = 61.4); BV (ml/100 mg): median = 24.0 (first quartile = 18.7, third quartile = 29.3); HPI (%): median = 78.4 (first quartile = 62.9, third quartile = 100); AP (ml/min): median = 45.9 (first quartile = 39.0, third quartile = 60.1); PP (ml/min): median = 9.0 (first quartile = 0.0, third quartile = 24.5); and TTP (seconds): median = 18.7 (first quartile = 16.3, third quartile = 26.5). The corresponding values calculated in cirrhotic surrounding parenchyma were P (ml/s/100 g): median = 11.5 (first quartile = 9.4, third quartile = 13.9); BV (ml/100 mg): median = 10.7 (first quartile = 7.1, third quartile = 14.2); HPI (%): median = 10.6 (first quartile = 8.7, third quartile = 11.9); AP (ml/min): median = 13.2 (first quartile = 10.1, third quartile = 15.5); PP (ml/min) median = 55.2 (first quartile = 40.1, third quartile = 79.5); and TTP (seconds): median = 41.7 (first quartile = 38.9, third quartile = 44.6). P, BV, HPI, and AP values were higher (P < .001), whereas PP and TTP were lower (P < .001) in HCC relative to the surrounding liver. Values of perfusion parameters in the cirrhotic liver of patients with and without HCC were not significantly different (P > .001). CONCLUSION In cirrhotic patients with HCC, perfusion computed tomographic technique can provide quantitative information about tumor-related angiogenesis.

Integrated PET/CT as a first-line re-staging modality in patients with suspected recurrence of ovarian cancer

PurposeThe aims of this study were to compare CT with PET/CT results in patients with suspected ovarian cancer recurrence and to assess the impact of the PET/CT findings on their clinical management.MethodsThirty-two consecutive patients with suspected ovarian cancer recurrence were retrospectively included in the study. Abdominal contrast-enhanced CT and PET/CT with [18F]FDG, in addition to conventional follow-up, were performed in all 32 patients. After the comparison between CT and PET/CT results, based on clinical reports, changes in the clinical management of patients (intermodality changes) due to PET/CT information were analysed.ResultsTwenty of the 32 patients were positive at CT (62.5%) versus 29 (90.6%) at PET/CT. Intermodality changes in management, i.e. use of a different treatment modality, after PET/CT examination were indicated in 14/32 (44%) patients. In particular, before PET/CT study, the planned management was as follows: wait-and-see in 7/32 (22%), further instrumental examinations in 4/32 (12%), chemotherapy in 10/32 (31%), diagnostic surgical treatment in 6/32 (19%) and surgical treatment in the remaining 5/32 (16%). After PET/CT study, wait-and-see was indicated in 1/32 (3%), further instrumental examinations in 7/32 (22%), chemotherapy in 16/32 (50%), diagnostic surgical treatment in 2/32 (6%) and surgical treatment in the remaining 6/32 (19%).ConclusionIntegrated PET/CT could detect tumour relapse in a higher percentage of patients than could CT. A change in the clinical management was observed in 44% of cases when PET/CT information was added to conventional follow-up findings.

Endometrial Cancer: Correlation of Apparent Diffusion Coefficient With Tumor Grade, Depth of Myometrial Invasion, and Presence of Lymph Node Metastases

OBJECTIVE The objective of our study was to investigate whether apparent diffusion coefficient (ADC) values of endometrial cancer differ from those of normal endometrium and myometrium and whether they vary according to histologic tumor grade, the depth of myometrial invasion, or lymph node status. SUBJECTS AND METHODS Seventy patients with histologically proved endometrial cancer and 36 control subjects with normal endometrium were enrolled in this prospective study. T2-weighted, dynamic T1-weighted, and diffusion-weighted images with b values of 0 and 1000 s/mm(2) were obtained of all patients. The ADC values of endometrial cancer, normal endometrium, and normal myometrium were recorded. Tumor grade, the depth of myometrial invasion, and lymph node status were assessed at postoperative histopathologic analysis. RESULTS The mean (± SD) ADC value (10(-3) mm(2)/s) of endometrial cancer (0.77 ± 0.12) was significantly lower than that of normal endometrium (1.31 ± 0.11, p < 0.0001) and normal myometrium (1.52 ± 0.21, p < 0.0001), with no overlap between the two former distributions. There was no significant difference between ADC values of endometrial cancer tissue in patients with tumor grade 1 (0.79 ± 0.08, n = 14), grade 2 (0.76 ± 0.14, n = 40), or grade 3 (0.75 ± 0.12, n = 16) (p = 0.67); in patients with deep (0.77 ± 0.13, n = 18) and those with superficial (0.76 ± 0.12, n = 52) myometrial invasion (p = 0.87); and in patients with (0.78 ± 0.10, n = 6) and those without (0.75 ± 0.14, n = 39) lymph node metastases (p = 0.64). CONCLUSION ADC values allow normal endometrium to be differentiated from endometrial carcinoma; however, they do not correlate with histologic tumor grade, the depth of myometrial invasion, or whether lymph node metastases are present.

Perfusion CT in cirrhotic patients with early stage hepatocellular carcinoma: Assessment of tumor-related vascularization

PURPOSE To assess the value of CT-perfusion in determining the quantitative vascularization features of early hepatocellular carcinoma (HCC) in cirrhotic patients. MATERIALS AND METHODS A total of 35 cirrhotic patients with single histologically proven HCC not exceeding 3cm in diameter underwent conventional triple-phase multidetector computed tomography (MDCT) examination. All patients were also examined with CT-perfusion (CTp) technique after i.v. injection of 50mL of iodinated contrast. Data were analyzed using a dedicated software which generated a quantitative map of liver parenchyma perfusion. The following parameters were assessed: hepatic perfusion (HP); blood volume (BV); arterial perfusion (AP); time to peak (TTP) and hepatic perfusion index (HPI). Univariate Wilcoxon signed rank test was used for statistical analysis. RESULTS In the 35 HCCs evaluated, the following quantitative data were obtained: HP (mL/s/100g): median=47.0 (1(st)qt=35.5; 3(st)qt=61.2); BV (mL/100mg): median=22.5 (1(st)qt=18.4; 3(st)qt=27.7); AP (mL/min): median=42.9 (1(st)qt=35.8; 3(st)qt=55.6); HPI(%): median=75.3 (1(st)qt=63.1; 3(st)qt=100); TTP(s): median=18.7 (1(st)qt=16.8; 3(st)qt=24.5). Perfusion values calculated in cirrhotic liver parenchyma were HP: median=10.3 (1(st)qt=9.1; 3(st)qt=13.2); BV: median=11.7 (1(st)qt=9.6; 3(st)qt=15.5); AP: median=10.4 (1(st)qt=8.6; 3(st)qt=11.3); HPI: median=17.5 (1(st)qt=14.3; 3(st)qt=19.7); TTP: median=44.6 (1(st)qt=40.3; 3(st)qt=50.1). HP, BV, HPI and AP were found to be significantly higher in HCC lesion than in liver parenchyma (p<0.001), while TTP was significantly lower (p<0.001). CONCLUSION CT-perfusion technique allows obtaining quantitative information about tumor-related vascularization of early HCC, in patients with liver cirrhosis.

Magnetic resonance imaging in endometrial carcinoma staging

Correct evaluation of myometrial infiltration is essential in patients with stage I and II endometrial cancer who are candidates for hysterectomy without lymphadenectomy, if extensive infiltration of the myometrium is not present. The aim of this study was to evaluate the use of magnetic resonance imaging (MRI) to improve staging of patients with endometrial cancer. Thirty patients with histological diagnosis of endometrial cancer were studied with MRI at 1.5 T and subsequently underwent abdominal hysterectomy. The MRI results were compared with those of the histological tests. MRI was performed with a 1.5-T magnet and spin-echo (SE) technique [repetition time/echo time (msec) = 2.000/35-90]. Contiguous 4-mm sections of were obtained from the sagittal plane. Clinical staging was not confirmed in two patients who presented with cervical extension of the tumor. The overall accuracy of MRI in determining the grade of myometrial and cervical invasion was 86 and 90%, respectively.

Role of MDCT in the Diagnosis of Hepatocellular Carcinoma in Patients with Cirrhosis Undergoing Orthotopic Liver Transplantation

OBJECTIVE The purpose of this study was to assess the diagnostic performance of MDCT in the detection of hepatocellular carcinoma in patients with cirrhosis undergoing orthotopic liver transplantation. MATERIALS AND METHODS Eighty-eight consecutively registered patients who underwent MDCT 6 months before liver transplantation were evaluated. The original reports were analyzed, and the CT images were retrospectively reevaluated independently by two radiologists who made the final interpretation in consensus. The imaging findings were correlated with histopathologic findings in the explanted livers on a patient-by-patient and a lesion-by-lesion basis. RESULTS Histopathologic examination revealed 139 hepatocellular carcinomas in 48 of the 88 patients. MDCT correctly depicted 89 of 139 hepatocellular carcinomas (sensitivity, 64%) at the original examination and 102 at reevaluation (sensitivity, 73.3%). Patient-by-patient analysis showed a specificity of 75% in the original reports and of 77.5% at reevaluation. A large number of false-positive nodules were found, most (59.2%) of them being smaller than 1 cm in diameter. CONCLUSION MDCT has reasonable sensitivity in the detection of hepatocellular carcinoma in patients with cirrhosis who undergo liver transplantation. Attention should be paid, however, to avoiding overestimation of the extent of disease.

High-grade endometrial cancer: value of [18F]FDG PET/CT in preoperative staging

ObjectiveThe purpose of this study was to assess the value of 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography ([18F]FDG PET/CT) in the primary staging of high-risk endometrial cancer patients. MethodsThis retrospective study was conducted on 32 consecutive patients with histological diagnosis of primary high-risk endometrial cancer, who underwent PET/CT with [18F]FDG in addition to conventional clinical and instrumental staging procedures. After surgery, [18F]FDG PET/CT findings were correlated with pathological findings on a patient-by-patient basis. The diagnostic accuracy of [18F]FDG PET/CT for primary cancer detection, lymph nodal involvement and distant metastases was assessed. Results[18F]FDG PET/CT could correctly detect primary tumor in 29 of the 32 high-risk patients, with a sensitivity of 90.6%. The overall [18F]FDG PET/CT patient-based sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 57.1, 100.0, 100.0, 86.4, and 88.5%, respectively, for revealing lymph nodal neoplastic involvement, and 100.0, 96.0, 87.5, 100.0, 96.9%, respectively, for detecting distant metastases. In particular, while the suspicion of distant metastases was documented by conventional imaging in only two patients, [18F]FDG PET/CT correctly identified metastatic lesions in seven patients (21.9% of cases). ConclusionThe major benefit provided in high-grade tumor patients by the use of [18F]FDG PET/CT in the primary staging of endometrial cancer is its ability to accurately detect distant metastases in the abdomen and extra-abdominal regions. [18F]FDG PET/CT adds relevant information that may influence patient management.