Application of C-11-acetate positron-emission tomography (PET) imaging in prostate cancer: systematic review and meta-analysis of the literature.

To review the literature on the application of (11) C-acetate positron-emission tomography (PET) imaging in prostate cancer. We systematically reviewed the available literature and presented the results in meta-analysis format. PubMed, SCOPUS, ISI web of knowledge, Science Direct, Springer, and Google Scholar were searched with 'Acetate AND PET AND Prostate' as keywords. All studies that evaluated accuracy of (11) C-acetate imaging in primary or recurrent prostate cancer were included, if enough data could be extracted for calculation of sensitivity and/or specificity. In all, 23 studies were included in the study. For evaluation of primary tumour, pooled sensitivity was 75.1 (69.8-79.8)% and specificity was 75.8 (72.4-78.9)%. For detection of recurrence, sensitivity was 64 (59-69)% and specificity was 93 (83-98)%. Sensitivity for recurrence detection was higher in post-surgical vs post-radiotherapy patients and in patients with PSA at relapse of >1 ng/mL. Studies using PET/computed tomography vs PET also showed higher sensitivity for detection of recurrence. Imaging with (11) C-acetate PET can be useful in patients with prostate cancer. This is especially true for evaluation of patients at PSA relapse, although the sensitivity is overall low. For primary tumour evaluation (localisation of tumour in the prostate and differentiation of malignant from benign lesions), (11) C-acetate is of limited value due to low sensitivity and specificity. Due to the poor quality of the included studies, the results should be interpreted with caution and further high-quality studies are needed.

H-indices of Academic Pediatricians of Mashhad University of Medical Sciences.

BACKGROUND: Web of Science, Scopus, and Google Scholar are three major sources which provide h-indices for individual researchers. In this study we aimed to compare the h-indices of the academic pediatricians of Mashhad University of Medical Sciences obtained from the above mentioned sources. METHOD: Academic pediatrician who had at least 5 ISI indexed articles entered the study. Information required for evaluating the h-indices of the included researchers were retrieved from official websites Web of Science (WOS), Scopus, and Google Scholar (GS). Correlations between obtained h-indices from the mentioned databases were analyzed using Spearrman correlation coefficient. Ranks of each researcher according to each database h-index were also evaluated. RESULTS: In general, 16 pediatricians entered the study. Computed h-indices for individual authors were different in each database. Correlations between obtained h-indices were: 0.439 (ISI and Scopus), 0.488 (ISI and GS), and 0.810 (Scopus and GS). Despite differences between evaluated h-indices in each database for individual authors, the rankings according to these h-indices were almost similar. CONCLUSION: Although h-indices supplied by WOS, SCOPUS, and GS can be used interchangeably, their differences should be acknowledged. Setting up "ReasercherID" in WOS and "User profile" in GS, and giving regular feedback to SCOPUS can increase the validity of the calculated h-indices.

Comparison between Impact factor, SCImago journal rank indicator and Eigenfactor score of nuclear medicine journals.

Despite its widespread acceptance in the scientific world, impact factor (IF) has been criticized recently on many accounts: including lack of quality assessment of the citations, influence of self citation, English language bias, etc. In the current study, we evaluated three indices of journal scientific impact: (IF), Eigenfactor Score (ES), and SCImago Journal rank indicator (SJR) of nuclear medicine journals. Overall 13 nuclear medicine journals are indexed in ISI and SCOPUS and 7 in SCOPUS only. Self citations, Citations to non-English articles, citations to non-citable items and citations to review articles contribute to IFs of some journals very prominently, which can be better detected by ES and SJR to some extent. Considering all three indices while judging quality of the nuclear medicine journals would be a better strategy due to several shortcomings of IF.

Prevalence of occult metastases in axillary sentinel lymph nodes of breast carcinoma.

Recently, sentinel lymph node biopsy (SLNB) has been accepted as a standard method of assessment of axillary lymph nodes in breast cancer patients with no clinical lymphadenopathy. There is no standard pathologic method to evaluate sentinel lymph nodes. The purpose of this study is to evaluate the frequency of occult lymph node metastasis in sentinel lymph nodes via serial sectioning and immunohistochemical study with cytokeratin and its relationship with other clinicopathologic factors. Paraffin-embedded blocks of axillary sentinel lymph nodes of breast cancer patients, biopsied in 2005-2009 and reported as negative, were reviewed with 3 µm sections, H and E staining and immunohistochemical study with an epithelial cytokeratin marker. Clinicopathologic data and relapse, if occurred was recorded and its relationship with occult metastasis was statistically analyzed. Sixty-eight sentinel pathology blocks of 66 patients (65 women and one man, median age 49 years) were investigated. Four cases (5.8%) of occult metastases were found, one by HE staining, and three cases with IHC (1 micrometastasis, 2 isolated tumor cells). Accuracy of reported cases was 94.1% upon re-examination. Sixty-four patients were followed after surgery and adjuvant therapy (range: 6-38 months, median: 21 months). No relapse was reported. There was no significant statistical relationship between occult metastasis and disease-free survival. Although 4 cases (5.8%) of sentinel lymph nodes were positive in the complementary study, with a median follow-up of 21 months, we found no difference in disease-free survival between these patients and others. To show a significant, however small, difference, one needs further research with a greater number of patients and longer follow-up.

Comparison between one day and two days protocols for sentinel node mapping of breast cancer patients.

Sentinel node biopsy can decrease the morbidity of breast cancer treatment significantly by sparing many patients of axillary lymph node dissection and resulting arm lymphedema. Despite widespread use of sentinel node mapping for breast cancer patients almost all aspects of this procedure are controversial; such as: type of the radiotracer, eligibility, time of injection, etc. One of these controversial issues is the efficacy of 2 days protocol (injection of the tracer on one day and sentinel node mapping and surgery on the following day). The main reason to perform 2 days protocol is the ease of operation room scheduling the patient does not need to complete injection and imaging in the nuclear medicine department. Despite widespread use of 2 days protocol for sentinel node mapping, very few studies have specifically evaluated this protocol in comparison to 1 day protocol and also the false negative rate which is the better index of sentinel node mapping success. Most of the above studies used tracers with large particle size such as (99m)Tc-sulfur colloid. Tracers with small particle size can theoretically be washed out from the real sentinel nodes and move to the second echelon nodes, so some recommended using large particle size radiotracers for the 2 days protocol. In this study, we compared the false negative rate of sentinel node mapping between 1 and 2 days protocols using intradermal injection of (99m)Tc-antimony sulfide colloid ((99m)Tc-SbSC) which has very small particle size. Eighty patients with early stage breast cancer (clinical stages of I and II) were evaluated. The diagnosis of the breast cancer was established by either excisional or core needle biopsy. The patients didn't take any chemotherapeutic drug before surgery and were divided into two groups: 1 day (Group I) and 2 days (Group II) protocols (45 in Group I and 35 in Group II). For Group I, periareolar intradermal injections of 0.5Bq/0.2mL (99m)Tc-SbSC were applied for patients without previous excisional biopsy. For patients with excisional biopsy two intradermal injections of 0.5Bq/0.2mL (99m)Tc-SbSC were used on both sides of the incision line. All injections were followed by gentle massage for 1min. For Group II, the same injection techniques were used but the dose of the tracer was doubled. Anterior, and lateral spot views were acquired 30min after the injection (5min/image, 128Χ128 matrix) using a dual head gamma camera (E.CAM Siemens) and parallel hole low energy high resolution collimator. The operation was performed 4h (for Group I) or 20h (for Group II) post radiotracer injection. All patients received 2mL patent blue V dye in a subdermal and periareolar fashion, 2min after general anesthesia. A surgical gamma probe (EUROPROBE, France) was used for harvesting the sentinel lymph nodes during surgery. As sentinel node was defined any blue node or any node with an ex vivo radioisotope count of twofold or greater than the axillary background. After completion of sentinel node biopsy, all patients underwent standard axillary lymph node dissection. The study was approved by our local ethical committee and all patients gave their informed consent before inclusion into the study. Quantitative data were expressed as mean±SD. For comparison between groups, independent sample student's t-test for quantitative variables, and chi-square or Fisher's exact tests for categorical variables were used. P-values less than 0.05 were considered statistically significant. SPSS version 11.5 was used for statistical analyses. The patients characteristics are shown in Table I. These general characteristics were not significantly different between the study groups (P>0.05). Detection rate was 100% for both Groups. The median number of sentinel nodes in both Groups was one sentinel node. The mean number of detected sentinel nodes during surgery was not statistically different between groups (1.28±0.7 and 1.32±0.6 for Group I and II respectively). One false negative sentinel node case with positive axillary nodes after dissection was found in both groups. This amounts to 6.25% and 6.66% false negative rate for Group I and II patients respectively. During surgery mean count rate at the injection site was 243123±22134 and 29430±2125 for Groups I and II, respectively. Mean count rate at the sentinel nodes was 4345±457 and 2375±356 for Groups I and II, respectively. Although the mean count rate at the injection site and the sentinel nodes were both higher in Group I of the study compared to Group II (P<0.0001 for both), the mean ratio of sentinel to injection site was statistically higher in Group II (P<0.0001). The 2 days protocol allows that the required lymphoscintigraphy imaging (including delayed views) can be performed before and during operation without any time limits. Most studies have reported similar to ours detection or false negative rates for both protocols. Our study showed comparable mean number of harvested sentinel nodes by the two protocols which is against the hypothesis of moving the tracer to other sentinel nodes by time. Others had similar results. The count rate of the sentinel nodes during surgery was statistically acceptable. Similar results have been reported by others too. Although we didn't evaluate radiation exposure in our study, this was acceptable in other studies and Buscombe et al showed a maximum effective dose of 2.6µSv/MBq for these patients and even assuming this highest value the patient exposure was very low compared to many other procedures. In conclusion, two days protocol gives the sentinel node biopsy team considerable flexibility and lymphoscintigrpahy imaging can be completed before surgery. Finding of the axillary sentinel node during surgery is also being easier. False negative rates as well as the detection rate for one day and two days protocols are comparable.