A New Perspective on the Effectiveness of FDG PET/CT in Predicting KRAS Mutation in Colon Cancer Cases.

Aim: The main aim of this study was to evaluate the effectiveness of 18F-fluorodeoxyglucose (18FDG) positron emission tomography/computerized tomography (PET/CT) parameters in predicting the Kristen rat sarcoma viral oncogene(KRAS) mutation status of patients with colon cancer. Materials and Methods: Between April 2013 and December 2020, 79 patients who were diagnosed with colon cancer by colonoscopy underwent staging 18FDG PET/CT with this diagnosis and met all the inclusion criteria were included in this study. Clinical and prognostic features and also imaging (18FDG PET/CT and magnetic resonance imaging) reports of the patients were collected and analyzed retrospectively. Results: KRAS mutation was seen in 32 of patients (40.5%). No significant difference was observed between KRAS mutant and wild-type patients in terms of clinical features (tumor location, findings regarding metastasis, T stage, and tumor differentiation grade in patients who underwent surgery) and overall survival. Progression-free survival was significantly shorter in KRAS mutant patients (p = 0.018). Primary tumor standardized uptake value (SUVmean) was significantly higher in KRAS mutant cases in the whole group (p = 0.024) and in patients in whom KRAS analysis was performed only in the primary lesion (p = 0.036). The cutoff value for predicting KRAS mutation status was 7.01 g/mL (area under the curve [AUC]: 0.650, confidence interval [CI] 95%, 0.56-0.74). Conclusions: When colon and rectal cancer cases were evaluated separately, the primary tumor SUVmean value was significantly higher in KRAS mutant colon cancer cases. However, its effectiveness in predicting KRAS mutation status was low, similar to other parameters in the literature.

Alterations in 18F-FDG Uptake Patterns may Limit Cross-sectional Evaluation of Adrenal Adenomas Using Single 18F-FDG PET/CT Imaging.

Adrenal adenomas are observed in up to 7% of the population and are predominantly non-functional, increased 18F-fluorodeoxyglucose (FDG) uptake is seen in only a small portion of them on 18F-FDG positron emission tomography/computed tomography (PET/CT) imaging. In this report, we present the sequential 18F-FDG PET/CT imaging findings of 2 patients with radiologically or pathologically confirmed adrenal adenomas who had severely altered 18F-FDG uptake patterns in adrenal lesions in different imaging studies of the same patient. In light of these findings, we wanted to highlight that evaluating adrenal adenomas as cross-sectional with semi-quantitative PET/CT parameters obtained from single imaging may cause misinterpretation.

The value of 18F-FDG PET/CT imaging in breast cancer staging.

The National Comprehensive Cancer Network (NCCN) guidelines recommend assessment with positron emission tomography with 2-deoxy-2-[fluorine-18]fluoro-D-glucose integrated with computed tomography (18F-FDG PET/CT) in staging of breast cancer, starting from the stage IIIA. Previously, PET/CT contributed to the accurate staging from the stage IIB. Our aim is to evaluate the contribution of 18F-FDG PET/CT in staging of breast cancer patients. A total of 234 patients were retrospectively evaluated. PET/CT was performed preoperatively in 114/234 and postoperatively in 120/234 patients. Initial staging was performed based on histopathological results in 125/234 and clinical results in 109/234 patients, according to the American Joint Committee on Cancer (AJCC) classification. All patients had a normal abdominal ultrasound and chest x-ray. Following PET/CT imaging, modification in the staging was performed in patients with the metastatic findings. In 42/234 (17.9%) patients hypermetabolic extra-axillary regional lymph nodes and in 65/234 patients (27.7%) distant metastatic involvement were detected with PET/CT. Modification in the staging was applied in 82/234 (35%) patients. Patient management was changed in 69/234 (29.4%) cases. The percentage of patients with upstaging, according to each stage, was as follows: IIA: 18.6%, IIB: 30%, IIIA: 46.3%, IIIB: 68.8%, and IIIC: 20.8%. In 43/43 patients, 99mTc-methylene diphosphonate (MDP) bone scan did not show additional bone metastasis. In 5/32 patients, metastatic involvement was detected with sentinel lymph node biopsy (SLNB), but preoperative PET/CT scan did not reveal hypermetabolic lymph nodes. Although our study was limited by the referral bias and lack of homogeneity in the referral group, PET/CT still significantly contributed to the accurate staging and management of our breast cancer patients, starting from the stage IIA.

Preparation of 99mTc-isosulfan blue for lymph node localization in rats 99mTc-isosulfan blue for lymph node localization.

The sentinel lymph node (SLN) is defined as the first regional lymph node to receive lymphatic drainage from a malignant tumor. Therefore, this node is a "sentinel" for second metastatic lymph node stations and for labeling regional tumor spread. For SLN detection, many surgeons preferred a combination of a preoperative injection of radiolabeled colloid and the intraoperative injection of blue dye. Under this combination protocol, nodes are considered to be "sentinel nodes" if they are radioactive and blue. The aim of this study is to develop a new single agent that combines both detection methods. For this purpose Isosulfan Blue (ISB) was radiolabeled by 99mTc with high labeling yield and stability. In vivo gamma scintigraphy studies were performed with rats. According to the scintigraphic studies, 99mTc-ISB shows rapid and high accumulation in both axillary (ALN) and popliteal lymph node (PLN). After the imaging study, extremity was opened and nodes were scanned for the radioactivity. According to performed study the lymph nodes were clearly seen to become blue and carried compound was sufficient to allow identification with a gamma probe. In conclusion, 99mTc-ISB has the potential to facilitate lymphatic mapping and subsequent sentinel node biopsy for solid malignancies such as breast cancer and melanoma.

Comparison of the clinicopathological features of invasive ductal, invasive lobular, and mixed (invasive ductal + invasive lobular) carcinoma of the breast.

BACKGROUND: In this retrospective analysis, the clinicopathological features and pattern of metastatic spread of invasive ductal carcinoma (IDC), invasive lobular carcinoma (ILC), and mixed ductal/lobular carcinoma (MDLC), together with the type and outcome of surgical intervention, were comparatively evaluated. METHODS: A total of 633 breast cancer patients with histopathological subtype IDC, ILC or MDLC were included in the study. The mean age was 52.6 ± 12.7 years. Follow-up period ranged between 0 and 33 (median 6.0) years. The groups were compared with respect to age, tumor size, nodal involvement, stage, hormonal therapy, multicentricity, multifocality, bilaterality, estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2)/neu, p53, and Ki67 expression, disease-free survival (DFS) and overall survival (OS) rates, and surgical approach. RESULTS: The distribution of patients was as follows: IDC 508 (80.3 %), ILC 78 (12.3 %), MDLC 47 (7.4 %). Among the parameters evaluated, statistically significant differences were observed in mean tumor size (IDC 2.5 ± 1.98 cm, ILC 3.0 ± 1.8 cm, MDLC 3.2 ± 2.4 cm), advanced T stage (T3 + T4) at diagnosis (IDC 14.7 %, ILC 21.4 %, MDLC 25.6 %), N stage (N0 was dominant in IDC and ILC; N3 was dominant in MDLC), tumor-node-metastasis (TNM) stage (stage II was dominant in IDC and ILC; stage III was dominant in MDLC), HER2/neu expression (IDC 23.8 %, ILC 11.8 %, MDLC 21.4 %), and frequency of bone metastasis (IDC 14.3 %, ILC 17.9 %, MDLC 25.5 %). CONCLUSIONS: MDLC-type tumors have different histopathological characteristics and are often diagnosed at advanced stage. However, their survival outcomes do not vary significantly from ILC and IDC.

The effect of subareolar isosulfan blue injection on pulse oximeter readings.

Besides several side effects including anaphylaxis, blue dyes are also known to cause false pulse oximeter readings. We aimed to examine the effects of subareolar isosulfan blue injection on pulse oximeter (SpO2) readings. The study group included 27 patients undergoing SLNB using both radiocolloid and isosulfan blue. Another group of 27 patients constituted the control group. Pulse oximeter readings were compared. SpO2 decline ≥4 % was defined as significant. All but one (96.2 %) of the patients in the study group showed SpO2 declines, compared to only one patient in the control group. Median ± Interqartile Range (IR) SpO2 decrease was 3.0 ± 4.0 % in the study and 0.0 ± 1.0 % in the control group (p < 0.001). There were significant (≥4 %) SpO2 decreases in 13 (48.1 %) patients in the study group. Statistically significant differences were noted between the two groups in all recordings between 15 and 180 min (p < 0.001). Initial time for SpO2 fall and the time to the lowest SpO2 recording were 10.0 ± 10.0 and 40.0 ± 30.0 min respectively. Using subareolar injection, the frequency of false readings is comparable with intraparenchymal injections, and is higher than intradermal injections. Time to peak SpO2 fall, and the recovery period, are delayed in the subareolar technique.

Sentinel lymph node biopsy in breast cancer: review on various methodological approaches.

AIMS AND BACKGROUND: Sentinel lymph node biopsy has been accepted as a standard procedure for early stage breast cancer. In this retrospective analysis, the results obtained with different methodological approaches using radiocolloid with or without blue dye were examined. METHODS: A total of 158 sentinel lymph node biopsies were performed in 152 patients. Group A (85 patients) underwent lymphatic mapping using a combination of periareolar intradermal radiocolloid and subareolar blue dye injections. Group B (73 patients) underwent only periareolar intradermal radiocolloid injection. One large tin colloid and two small radiocolloids (nanocolloid of serum albumin -NC- and colloidal rhenium sulphide -CS-) were used. RESULTS: Successful lymphatic mapping was attained in 157 of 158 procedures (99.4%). Radiocolloids localized sentinel lymph nodes in 99.4% and blue dye in 75.3% of the cases. The number of sentinel lymph nodes removed was greater in nanocolloid and colloidal rhenium sulphide groups (P ≤0.05). Among 60 metastatic sentinel lymph nodes, frozen section analysis using hematoxylin and eosin staining failed to detect 1 macro- and 10 micrometastasis. Radiocolloid uptake was higher in sentinel lymph nodes accumulating blue dye (1643 ± 3216 counts/10 sec vs 526 ± 1284 counts/10 sec, P <0.001). Higher count rates were obtained by using larger sized colloids (median and interquartile range: tin colloid, 2050 and 4548; nanocolloid, 835 and 1799; colloidal rhenium sulphide, 996 and 2079; P = 0.01). Only 2 extra-axillary sentinel lymph nodes were visualized using periareolar intradermal injection modality. CONCLUSIONS: Radiocolloids were more successful than blue dye in sentinel lymph node detection. More sentinel lymph nodes were harvested with small colloids, but different sized radiocolloids were similarly successful. Sentinel lymph nodes having higher radiocolloid uptake tended to accumulate blue dye more frequently. Sentinel lymph nodes manifested higher count rates when a larger colloid was used. Frozen section was very successful in detecting macrometastatic disease in sentinel lymph nodes, but the technique failed in most of the micrometastates.

The importance of staging systems for the determination of prognosis of well-differentiated thyroid cancer.

OBJECTIVE: In this study, we aimed to determine the significance of the staging systems (EORTC, De Groot, MACIS, and TNM) on the prognosis of well-differentiated thyroid cancer patients who underwent surgery in our clinics. MATERIAL AND METHODS: This retrospective study included 181 patients who were operated between December 1995-December 2007, with a diagnosis of thyroid cancer. In order to obtain data related to cancer staging, a computer program for PDA was developed to facilitate parameter recording. Survival analysis was performed. The findings were compared to the predicted rates by the staging systems. RESULTS: According to the De Groot staging system, stage 1 and stage 2 patients' results were compatible, but stage 3 and 4 patients' results were different (stage 3; 87% versus 66.6%, stage 4; 35% versus 100%, p=0.04). In the MACIS staging system, 20-year survival rates are determined and comparison should not be made due to insufficient follow-up period in this study. When compared to the EORTC staging system, stage 3 and stage 4 patients' results were determined different (stage 3; 51% versus 100%, stage 4; 33% versus 50%, p=0.02). The most consistent results in terms of prognosis was determined in comparison with the TNM staging system (stage 1; 100% versus 97.8%, stage 4; 45.3% versus 50%). CONCLUSION: Many classification systems are proposed for well-differentiated thyroid cancer, to predict the behavior of the tumor. In this study, we concluded that for determination of prognosis in well-differentiated thyroid cancer, the TNM staging system could best predict prognosis consistent with clinical findings.

Sentinel lymph node biopsy in breast cancer: predictors of axillary and non-sentinel lymph node involvement.

BACKGROUND: Sentinel lymph node biopsy is a standard method for the evaluation of axillary status in patients with T1-2N0M0 breast cancers. AIMS: To determine the prognostic significance of primary tumour-related clinico-histopathological factors on axillary and non-sentinel lymph node involvement of patients who underwent sentinel lymph node biopsy. STUDY DESIGN: Retrospective clinical study. METHODS: In the present study, 157 sentinel lymph node biopsies were performed in 151 consecutive patients with early stage breast cancer between June 2008 and December 2011. RESULTS: Successful lymphatic mapping was obtained in 157 of 158 procedures (99.4%). The incidence of larger tumour size (2.543±1.21 vs. 1.974±1.04), lymphatic vessel invasion (70.6% vs. 29.4%), blood vessel invasion (84.2% vs. 15.8%), and invasive lobular carcinoma subtype (72.7% vs. 27.3%) were statistically significantly higher in patients with positive SLNs. Logistic stepwise regression analysis disclosed tumour size (odds ratio: 1.51, p=0.0021) and lymphatic vessel invasion (odds ratio: 4.68, p=0.001) as significant primary tumour-related prognostic determinants of SLN metastasis. CONCLUSION: A close relationship was identified between tumour size and lymphatic vessel invasion of the primary tumour and axillary lymph node involvement. However, the positive predictive value of these two independent variables is low and there is no compelling evidence to recommend their use in routine clinical practice.

A new and simple predictive formula for non-sentinel lymph node metastasis in breast cancer patients with positive sentinel lymph nodes, and validation of 3 different nomograms in Turkish breast cancer patients.

BACKGROUND: Nomogram accuracies for predicting non-sentinel lymph node (SLN) involvement vary between different patient populations. Our aim is to put these nomograms to test on our patient population and determine our individual predictive parameters affecting SLN and non-SLN involvement. PATIENTS AND METHODS: Data from 932 patients was analyzed. Nomogram values were calculated for each patient utilizing MSKCC, Tenon, and MHDF models. Moreover, using our own patient- and tumor-depended parameters, we established a unique predictivity formula for SLN and non-SLN involvement. RESULTS: The calculated area under the curve (AUC) values for MSKCC, Tenon, and MHDF models were 0.727 (95% confidence interval (CI) 0.64-0.8), 0.665 (95% CI 0.59-0.73), and 0.696 (95% CI 0.59-0.79), respectively. Cerb-2 positivity (p = 0.004) and size of the metastasis in the lymph node (p = 0.006) were found to correlate with non-SLN involvement in our study group. The AUC value of the predictivity formula established using these parameters was 0.722 (95% CI 0.63-0.81). CONCLUSION: The most accurate nomogram for our patient group was the MSKCC nomogram. Our unique predictivity formula proved to be as equally effective and competent as the MSKCC nomogram. However, similar to other nomograms, our predictivity formula requires future validation studies.

The effect of radiocolloid preference on major parameters in sentinel lymph node biopsy practice in breast cancer.

INTRODUCTION: The possible effects of radiocolloid preference on sentinel lymph node biopsy (SLNB) were investigated. METHODS: A total of 200 patients with T1-2N0M0 breast cancer were evaluated. The first 100 patients underwent SLNB using (99m)Tc tin colloid (TC) and the next 100 using (99m)Tc nanocolloid (NC). Radiocolloid was injected intradermally at four quadrants of the periareolar region the day before surgery. All patients underwent lymphoscintigraphy 1 h after injection. All nodes having fourfold activity of the background were harvested using gamma probe. RESULTS: Sentinel lymph node (SLN) identification rate by gamma probe was 98% in each group. The number of SLNs identified by lymphoscintigraphy, gamma probe and pathological evaluation was 1.39 ± 0.7, 1.70 ± 1.0 and 2.23 ± 1.70 in the TC and 2.03 ± 0.94, 2.60 ± 1.36 and 3.05 ± 1.90 in the NC group, respectively (P<.05). Metastatic SLN was found in 24 (24.4%) of 98 patients in the TC group and 41 (41.8%) of 98 patients in the NC group (P=.04). None of the patients showed dispersion to internal mammarian lymph nodes. Lymphatic vessel visualization was observed in eight (8.1%) of 98 TC patients and in 47 (47.9%) of 98 NC patients (P=.000). SLNs were the only metastatic node(s) in 54.1% of TC and 73.1% of NC patients. CONCLUSION: The periareolar intradermal injection technique gives a high detection rate in the localization of SLNs independently from the choice of the tracer. Mean SLN numbers and lymphatic vessel visualization frequency were significantly higher using a smaller albumin Tc-99m nanocolloid as compared to a stannous fluoride Tc-99m tin colloid. The results of our study support the idea that the influence of increased number of SLNs on positive SLN frequency is critical.

Problematic aspects of sentinel lymph node biopsy and its relation to previous excisional biopsy in breast cancer.

PURPOSE: The aim of the study is to review problematic aspects of sentinel lymph node biopsy (SLNB) and to evaluate the influence of a previous excisional biopsy on these problems. MATERIALS AND METHODS: A total of 345 patients were evaluated retrospectively, 156 of them had a previous biopsy. Tc-99m tin colloid was injected the day before surgery at 4 quadrants around the areola intradermally. Problems complicating SLNB are reviewed in 3 topics: visualization or gamma probe detection problems, dilated lymphatic channels, and misleading activity accumulation. RESULTS: SLN detection rate and mean sentinel lymph node numbers were as follows in patients with and without biopsy, respectively: 95.5% versus 99.4% and 1.71 +/- 0.97 versus 1.70 +/- 0.92. Problems complicating the procedure occurred in 20 patients (5.8%). Among these 20 patients, 15 had a prior excisional biopsy, and incisions were located in the upper, outer and periareolar zones. Visualization or gamma probe detection problems occurred in 8 patients. Except for one with faint uptake in a sentinel node, all had a prior biopsy. Lymphatic channel dilatation complicated the procedure in 7 patients. Of these 7 patients, 4 had a previous biopsy. Misleading activity accumulations compromised SLNB in 5 patients, 4 of whom had a prior biopsy. CONCLUSION: Although SLNB is still applicable with a high success rate in cases with excisional biopsy, a review of problematic aspects of SLNB demonstrated a relation with the presence of a previous biopsy and its localization. The demonstration of nonvisualization preoperatively and the precise localization of atypically located activity accumulation may be helpful in the prevention of potential complications.

Single photon emission tomography following posterior fossa surgery in patients with and without mutism.

MATERIALS AND METHODS: We designed a prospective study to investigate single photon emission tomography (SPECT) findings in patients with or without mutism who had undergone posterior fossa surgery. These patients had a (99m)Tc-hexamethylpropyleneamine oxime-SPECT scan postoperatively. SPECT was performed between the 1st and 2nd week after surgery. The patients with cerebellar mutism had a second SPECT scan after regaining their power of speech. The patients were evaluated in terms of age, gender, preoperative and postoperative neurological and radiological findings, tumor size and location, vermian incision and histopathology. RESULTS: Six girls and 5 boys, ranging in age from 3 to 11 years who had undergone posterior fossa tumor surgery were included in this study as controls. Their tumors were located in the vermis and fourth ventricle in 8 patients, in the cerebellar hemisphere in 1, fourth ventricle in 1, and 1 patient had a fourth ventricular tumor extending the cerebello-pontine angle. The histopathology of the tumors was as follows: astrocytoma in 5 patients, ependymoma in 3, medulloblastoma in 1, dermoid tumor in 1, and choroid plexus papilloma in 1 patient. Postoperative cerebellar mutism developed in 2 girls and 1 boy whose ages ranged from 2 to 5 years. Pathological examination revealed 2 medulloblastomas and 1 ependymoma. Mutism developed 2 to 4 days after surgery. All of the patients with cerebellar mutism showed either clinical or radiological signs and symptoms of brain stem involvement. SPECT findings were similar in the patients with cerebellar mutism and in those without. CONCLUSIONS: SPECT findings are not specific enough to explain how cerebellar mutism occurs. Clinical signs of brain stem involvement seem to be a significant risk factor in the development of cerebellar mutism.