Claudio Pizzocaro

Possible additional value of 18FDG-PET in managing pancreas intraductal papillary mucinous neoplasms: Preliminary results

Although some clinical and radiological features may predict malignancy presence in intraductal papillary mucinous pancreas neoplasms, preoperative diagnosis remains difficult. In this study we present 7 patients with Intraductal Papillary Mucinous Neoplasm (IPMN) studied both with 18FDG-PET and magnetic resonance cholangiopancreatography (MRCP). A focal hypermetabolism was documented in 2 patients (the standardized uptake value in the neoplastic foci was 6.7 and 9), while absence of FDG uptake in the neoplasm area was recorded in the remaining 5 cases. Mean follow-up was 27 months (range 21–34). The final judgement was benign IPMN in 5 cases and malignant IPMN in 2. PET scan always correctly predicted the presence or absence of malignancy, while MRCP failed to detect malignancy in 3/7 cases. In conclusion, this preliminary experience suggests that 18FDG-PET may prove useful for malignancy detection in IPMN, improving differential diagnosis with benign intraductal papillary growth by functional data.

IQ SPECT Allows a Significant Reduction in Administered Dose and Acquisition Time for Myocardial Perfusion Imaging: Evidence from a Phantom Study

We recently demonstrated in a clinical trial the ability of a new protocol, IQ SPECT, to acquire myocardial perfusion imaging (MPI) studies in a quarter of the time (12 s/view) of the standard protocol, with preserved diagnostic accuracy. We now aim to establish the lower limit of radioactivity that can be administered to patients and the minimum acquisition time in SPECT MPI using an IQ SPECT protocol, while preserving diagnostic accuracy. Methods: An anthropomorphic cardiac phantom was used to acquire clinical rest scans with a simulated in vivo distribution of 99mTc-tetrofosmin at full dose (740 MBq) and at doses equal to 50%, 25%, and 18%. For each dose, 2 sets of images were acquired, with and without a transmural defect (TD). Variable acquisition times were also used for each dose. We analyzed raw data and reconstructed images, including no correction and correction for attenuation (AC), for scatter (SC), or for both (ACSC). Images were evaluated qualitatively and quantitatively in order to assess left ventricle (LV) wall thickness (full width at half maximum of the medial sections), TD, and cavity contrast in the LV wall. Data were compared across different acquisition times within the same dose and across doses with the same acquisition time. Results: Images were visually scored as very-good quality except those acquired with 4 s/view or less at 100% dose and 6 s/view or less with 50%, 25%, or 18% dose, due to false-positive defects. LV wall thickness was not significantly different among all acquisitions. Cavity contrast remained unchanged within the same dose for all images and tended to be higher in AC and ACSC images. TD contrast remained unchanged within the same dose for all images. In SC and no-correction images, contrast was constant for all doses. AC images had significantly higher TD contrast values, and ACSC images showed a drop in TD contrast for a 50% dose. Conclusion: IQ SPECT effectively preserved both image quality and quantitative measurements with reduced acquisition time or administered dose in a phantom study. These findings suggest that approximately one eighth of the time, compared with standard protocols with a full dose, or a lower dose at an acquisition time of 12 s/view can be applied in MPI without the loss of diagnostic accuracy.

Role of 11C-choline positron emission tomography/computed tomography in evaluating patients affected by prostate cancer with suspected relapse due to prostate-specific antigen elevation

PurposeThe aim of this study was to evaluate the accuracy of 11C-choline positron emission tomography/computed tomography (PET/CT) in restaging patients affected by prostate cancer and suspected relapse due to prostate-specific antigen (PSA) increase. We also aimed to determine a PSA cutoff that is most suited to the study in terms of best compromise between sensitivity and specificity. Secondary endpoints were a comparison between 11C-choline PET/CT and histological results, clinical findings, and radiological imaging (CT and magnetic resonance imaging).Materials and methodsWe retrospectively evaluated 210 patients (median ± SD age 70 ± 7 years) affected by prostate cancer who underwent 11C-choline PET/CT.Results11C-choline PET/CT imaging was positive in 116 (55.2%) patients and negative in 94 (44.8%). Receiver operating characteristic (ROC) analysis showed that the highest accuracy (sensitivity 76.8%, specificity 92.5%) for the whole population was achieved when the PSA level of 1.26 ng/ml level was used as the cutoff value for interpreting the results (P = 0.0001 and the area under the ROC curve AUC 0.897). For patients treated with surgery or surgery plus radiotherapy the cutoff was 0.81 ng/ml (sensitivity 73.2%, specificity 86.1%). For patients treated with radiotherapy alone, the cutoff was 2.0 ng/ml (sensitivity 81.8%, specificity 92.9%).ConclusionOur results indicate that 11C-choline PET/CT is a useful diagnostic tool in patients affected by prostate cancer and a relapsed PSA level. The highest accuracy for all patients is obtained with a PSA cutoff level of 1.26 ng/ml, above which the imaging study is performed (0.81 ng/ml for patients treated with surgery or surgery plus radiotherapy and 2.0 ng/ml for patients treated with radiotherapy alone).

New tracers for the imaging of the medullary thyroid carcinoma

I-MIBG and 99Tcm(V)-DMSA have been recently proposed as scintigraphic markers of the medullary thyroid carcinoma (MTC). Thirty two patients were examined with 131I- or 123I-MIBG and 26 of these were re-examined with 99Tcm(V)-DMSA (planar and SPECT). From our experience we can draw the following conclusions: (1) the scintigraphic attempt was useless in patients with normal levels of plasma calcitonin (CT): (2) in patients with high plasma CT levels, the sensitivity of the MIBG was better in familiar (3/3 true positive) than in sporadic disease (7/21 true positive; overall sensitivity = 42%); the 99Tcm(V)-DMSA was positive in 16/19 cases, (overall sensitivity = 84%) even in cases which had been false negative with MIBG (6 patients); (3) no false positive results were found; (4) the scan with 99Tcm(V)-DMSA is then suggested as the first imaging approach during the follow up in patients affected by MTC and still having high levels of plasma CT. The MIBG scan should be limited to the patients in whom the possible use of MIBG therapy has to be investigated.

The Role of Neuroimaging in Evaluating Patients Affected by Creutzfeldt–Jakob Disease: A Systematic Review of the Literature

Diagnosis of Creutzfeldt–Jakob disease during life can be challenging since the huge variability of the symptoms which can be observed, especially in its early stages, may simulate other common forms of dementia. In latest years, noninvasive techniques such as magnetic resonance, positron emission tomography, and single‐photon emission tomography have been evaluated to help clinical neurologists to provide a definite diagnosis.

Cetuximab in the treatment of metastatic mucoepidermoid carcinoma of the salivary glands: A case report and review of literature

IntroductionPatients with metastatic mucoepidermoid carcinoma of salivary glands have a poor outcome. The epidermal growth factor receptor protein is overexpressed in approximately 70% of mucoepidermoid carcinoma patients and may represent a therapeutic target. However, whether treatment with anti-epidermal growth factor receptor agents is effective is unclear and clinical trials are difficult due to the rarity of the disease. Here we assessed the activity of cetuximab in mucoepidermoid carcinoma on a molecular basis.Case presentationWe present the case of a 40-year old Caucasian man with a mucoepidermoid carcinoma of the major salivary glands who developed distant bone and visceral metastases despite platinum-based chemotherapy. Epidermal growth factor receptor was overexpressed and fluorescence in situ hybridization analysis demonstrated a chromosome 7 polysomy. The patient was treated with the monoclonal antibody cetuximab in combination with cisplatin. After 11 doses of cetuximab, the patient developed brain metastases but evidence of response was documented at all extracranial metastatic sites.ConclusionThis case report indicates that cetuximab can be active in mucoepidermoid carcinoma and may restore sensitivity to cisplatin in platinum-treated patients. Cetuximab does not cross the blood brain barrier and may select a metastatic clone to home the central nervous system while responding at other sites.

Nodal staging in localized melanoma. The experience of the Brescia Melanoma Unit

BACKGROUND AND OBJECTIVES We report our experience with patients affected by cutaneous melanoma undergoing sentinel node (SN) biopsy. METHODS From November 1997 to October 2000 we performed 128 selective lymphadenectomies (SN biopsy) on 127 patients with cutaneous melanoma with Breslow thickness>1 mm or regression or ulceration. Age, sex, tumour location ad histology were recorded. RESULTS Two hundred and thirty eight SNs were identified by lymphoscintigraphy in 167 lymphatic stations, 236 of them were identified intraoperatively using a gamma probe and patent blue V injection. Twenty-one patients had SNs with melanoma metastases (15.8%), 12 patients in the groin, eight patients in the axilla and one patient in the neck. After therapeutic lymphadenectomy eight more lymph nodes with metastases of melanoma were found in the specimens of three patients. After a follow-up ranging from 10 to 56 months the results are that 111 patients are free of disease. Ten patients died. Three patients have visceral metastases and are alive. One patient has developed two more melanomas. One patient was lost to follow-up. CONCLUSIONS Our data confirm the clinical reliability of the SN technique in melanoma; for optimisation of the therapeutic strategy, this technique might be considered the standard method of nodal staging in the evaluation of melanoma patients.

Positron Emission Tomography for the Response Evaluation following Treatment with Chemotherapy in Patients Affected by Colorectal Liver Metastases: A Selected Review

The aim of the present paper is to review the scientific literature concerning the usefulness of 18F-FDG PET/CT in the evaluation of response to chemotherapy in patients affected by liver metastases from colorectal cancer. Material and Methods. Studies were identified by searching PubMed electronic databases. Both prospective and retrospective studies were included. Information regarding the figure of merit of PET for the evaluation of therapy response was extracted and analyzed. Results. Existing data suggests that 18F-FDG PET/CT may have an outstanding role in evaluating the response. The sensitivity of PET in detecting therapy response seems to be greater than conventional imaging (CT and MRI). PET/CT response is strictly related to better overall survival and progression-free survival. Conclusions. PET/CT is more than a promising technique to assess the response to chemotherapy in colorectal and liver metastases. However, to be fully validated, this examination needs further studies by recruiting more patients.

Proposal for an optimized protocol for intravenous administration of insulin in diabetic patients undergoing 18f-fdg Pet/ct

The objective of this study was to evaluate the usefulness and impact of insulin administration before an 18F-FDG PET/computed tomography (CT) examination in diabetic patients in order to propose an optimized protocol that can reduce blood glucose levels without increasing muscular 18F-FDG uptake. A total of 130 patients underwent an 18F-FDG PET/CT. Twenty patients had glucose levels greater than 180 mg/dl and received endovenous insulin before 18F-FDG injection (group 1); 10 patients had glucose levels greater than 160 mg/dl and lower than 200 mg/dl and received no insulin (group 2); 100 patients were euglycemic (group 3). Biodistribution was adequate in 19 of 20 patients in group 1. Values of standardized uptake value in the gluteal muscle were 0.50±0.18 for group 1, 0.48±0.10 for group 2, and 0.49±0.08 for group 3; no significant differences in muscular 18F-FDG uptake could be found among the three groups. No adverse events were recorded. In conclusion, our protocol has been demonstrated to be safe and effective, with only a minor impact on glucose biodistribution and apparently without affecting PET accuracy.

Sentinel node biopsy in breast cancer: the experience of Brescia Civic Hospital.

The accuracy of the sentinel node technique in the evaluation of axillary node involvement in breast cancer was evaluated in 83 consecutive patients with monofocal T1–2 carcinoma, who were clinically N0 and who underwent lymphoscintigraphy with 99mTc-colloid integrated with intraoperative sentinel node detection by a portable probe. Lymphoscintigraphy revealed at least one sentinel node in 75 patients (90.4%), always identified by the probe. In eight patients (9.6%) the sentinel node was detected neither by lymphoscintigraphy nor by the probe. All removed lymph nodes were analyzed by hematoxylin-eosin histology and the sentinel node by immunostaining. In 28/75 patients (37.3%) at least one metastatic axillary lymph node was detected; in 16 of the 28 N+ subjects (57%) only the sentinel node was positive. The false negative rate (sentinel node negative/other axillary lymph nodes positive) was 17.85% (5/28 patients). In 9/23 patients (39%) micrometastases were found in the sentinel node only. In conclusion, specific sentinel node positivity in 57% of cases supports the validity of the sentinel node concept. Moreover, nine patients would have been considered No by standard hematoxylin-eosin histology without sentinel node-aided immunostaining. A 17.8% false negative rate calls for caution in patients with negative sentinel nodes.