Taylan Kara

The role of fluorodeoxyglucose-positron emission tomography/computed tomography in differentiating between benign and malignant adrenal lesions.

ObjectivesThis retrospective study was designed to investigate the clinical role of whole-body positron emission tomography/computed tomography (PET/CT) by using 2-[18F]fluoro-2-deoxy-D-glucose (FDG), for the evaluation of adrenal lesions and to find the best index to distinguish benign from malignant lesions in various cancer patients. Materials and methodsA total of 81 patients (55 male and 26 female, age range: 31–81 years, mean: 61.5) who had confirmed primary malignancies (lung cancer in 47 patients, gastrointestinal malignancies in 13 patients, malignant melanoma in one patient, renal cell cancer in three patients, mesothelioma in two patients, breast carcinoma in nine patients, cervical cancer in one patient, ovarian cancer in two patients, pheochromocytoma in one patient, unknown primary in two patients) underwent PET/CT examinations for cancer screening, staging, restaging, and detection of suspected recurrence. Of the 81 patients, 104 adrenal lesions (34 benign and 70 malignant adrenal lesions) were shown by CT. On visual analysis of PET/CT imaging, adrenal uptake was based on a three-scale grading system. For final assessment standards of references for adrenal malignant lesions was based on biopsy (n=2), interval growth, or reduction after chemotherapy. An adrenal lesion, which remained unchanged on clinical and imaging follow-up of at least 7 months (mean follow-up time 19.31 months±6.46, range 7–30 months), was decided as a benign lesion. ResultsIn adrenal malignant lesions maximum standardized uptake value (SUVmax) (8.82±4.47) was higher than that of adrenal benign lesions (3.02±1.15, P<0.0001). In the differentiation of adrenal benign and malignant lesions, a CT threshold of 10 Hounsfield units corresponded to a sensitivity of 64.7%, specificity of 98.6%, and accuracy of 87.5%. An SUVmax cut-off value of 2.5 corresponded to a sensitivity of 100%, specificity of 38.2%, and accuracy of 80%. An SUVmax cut-off value of 4.2 corresponded to a sensitivity of 88.6%, specificity of 88.2%, and accuracy of 88.5%. The ratio of tumor SUVmax to liver SUVmean was 3.61±1.77 for adrenal malignant lesions whereas it was 1.20±0.38 for adrenal benign lesions (P<0.0001). T/L SUV ratio cut-off value of 1.8 corresponded to a sensitivity of 87%, specificity of 91%, and accuracy of 88.5%. T/L SUV ratio cut-off value of 1.68 corresponded to a sensitivity of 90%, specificity of 91.1%, and accuracy of 90.4%. Conclusion2-[18F]fluoro-2-deoxy-D-glucose-PET/CT improves the diagnostic accuracy in the differentiation of benign from malignant adrenal lesions in various cancer patients. Combined information obtained from PET/CT (SUVmax, T/L SUV ratio, visual analysis) and unenhanced CT (size, Hounsfield units measurement) is recommended for better differentiation.

The value of dynamic contrast-enhanced MRI in the detection of recurrent prostate cancer after external beam radiotherapy: correlation with transrectal ultrasound and pathological findings.

PURPOSE To assess the effectiveness of dynamic contrast-enhanced (DCE) T1- and T2-weighted magnetic resonance imaging (MRI) during the follow-up of patients with prostate cancer after undergoing external beam radiotherapy (EBRT) and to compare these imaging findings to pathological and transrectal ultrasound (TRUS) findings. MATERIALS AND METHODS In this retrospective study, the MRI findings of 20 patients who had prostate cancer and were treated with EBRT were evaluated to detect tumor recurrence. The MRI findings were compared to those that had been obtained by TRUS and pathological analysis. RESULTS The sensitivity and specificity of TRUS in the detection of tumor recurrence in patients who had undergone EBRT were 53.3% and 60%, respectively. In the same group of patients, the sensitivity and specificity of T2-weighted MRI were 86% and 100%, respectively. Strikingly, the sensitivity and specificity of DCE T1-weighted MRI in the diagnosis of recurrent prostate cancer were 93% and 100%, respectively. The accuracy of the DCE T1-weighted images in the detection of recurrence was significantly higher in comparison to that obtained using T2-weighted images. CONCLUSION During the follow-up of these patients, TRUS without the use of any other imaging or biochemical modality is not a sufficient method for the detection of prostate cancer recurrence. DCE T1-weighted MRI increases the sensitivity of MRI alone for the detection of recurrence during the follow-up of prostate cancer patients who have been treated with EBRT. Thus, DCE T1-weighted MRI must be used as part of the routine MRI analysis to check for tumor recurrence in patients with prostate cancer.

Multidetector-row computed tomography findings of sclerosing mesenteritis with associated diseases and its prevalence

PurposeOur aim was to report the multidetector-row computed tomography (MDCT) findings of sclerosing mesenteritis, which is a rare disease characterized by chronic nonspecific inflammation of mesenteric adipose tissue. It has associated diseases, and we explored its prevalence.Materials and methodsA total of 2100 patients were evaluated retrospectively for sclerosing mesenteritis between December 2007 and May 2009. Signs and symptoms, associated diseases, laboratory data, surgical histories, and related findings of a misty mesentery, which corresponds to sclerosing mesenteritis on MDCT, were recorded.ResultsMisty mesentery findings were seen in 51 (2.43%; 35 men) patients. Their ages ranged between 33 and 78 years (mean 56.2 years). The most frequent complaint of patients was abdominal pain (n = 19; 37.2%). The most prominent possible causative and/or associated factors in our study were malignancy (n = 9; 17.6%), previous surgery (n = 17; 33.3%), smoking (n = 20; 39.2%), coronary artery disease (n = 9; 17.6%), urolithiasis (n = 10; 19.6%), hypertension (n = 18; 35.2%), hyperlipidemia (n = 13; 25.5%), and diabetes mellitus (n = 11; 21.5%). On MDCT, density values in mesenteric fat (−62.8 ± 18.6 HU) were significantly higher than the values for subcutaneous (−103.9 ± 5.8 HU) and retroperitoneal (−105 ± 6 HU) fatty tissues (both P < 0.0001). A partially hyperdense stripe (n = 37; 72.6%), well-defined soft tissue nodules (100%), hypodense fatty halo enclosing vessels (n = 1; 1.9%), and nodules (n = 12; 23.5%) were demonstrated in most of the patients.ConclusionThe diagnosis of sclerosing mesenteritis has increased with the more frequent use of MDCT and the popularization of the DICOM viewer. Defined hallmarks on MDCT can be helpful for differentiating sclerosing mesenteritis from other pathologies.

Unusual presentation of an anterior sacral meningocele: magnetic resonance imaging, multidetector computed tomography, and fistulography findings of bacterial meningitis secondary to a rectothecal fistula

An anterior sacral meningocele, a rare congenital anomaly, manifested in a previously healthy 44-year-old woman with findings of meningitis, including headache, vomiting, unconsciousness, and fever. Nontraumatic pneumocephalus, tetraventricular hydrocephalus, fluid-fluid level at the lateral ventricles, and pial enhancement were observed on multidetector computed tomography. A ventricular drainage catheter was placed to decompress the hydrocephalus, and drainage was performed urgently. Escherichia coli was isolated from the drainage material. Whole-spine magnetic resonance imaging and fistulography were undertaken on the third day after admission to evaluate for anal and urinary incontinence and pareses of both upper and lower extremities. Spinal arachnoiditis, tethered cord, dysgenesis of the sacrum, and a rectothecal fistula were demonstrated. Specific antibiotic treatment and surgery for fistula tract excision were performed.

Gray scale histogram analysis of solid breast lesions with ultrasonography: can lesion echogenicity ratio be used to differentiate the malignancy?

PURPOSE The aim of this study was to investigate the diagnostic performance of lesion echogenicity ratios (LER) calculated by image histogram analysis for distinction of malignant and benign breast lesions. MATERIAL AND METHODS A total of 55 patients (mean age, 44 years) with 59 lesions were included. Ultrasound images were analyzed retrospectively. RESULTS Mean LER values in benign and malignant lesions were 1.63±0.41 and 3.1±0.87, respectively. The difference between LER values of benign and malignant breast lesions was statistically significant (P<.001). CONCLUSION LER can be used as an adjunct ultrasound parameter to differentiate between benign and malignant breast lesions.

The value of FDG-PET/CT in the post-treatment evaluation of endometrial carcinoma: A comparison of PET/CT findings with conventional imaging and CA 125 as a tumour marker

OBJECTIVES This retrospective study was designed to assess the value of positron emission tomography/computed tomography imaging (PET/CT) in the post-treatment evaluation of the patients with endometrial carcinoma and to compare PET/CT scan with conventional imaging (CI) including computed tomography (CT), ultrasonography (US) and magnetic resonance imaging (MRI) and CA 125 with both 20U/ml and 35U/ml cut-off values. MATERIALS AND METHODS A total of 31 patients who were treated for histopathologically proven endometrial adenocarcinoma, underwent PET/CT examination for restaging and suspected recurrence. Thirty five PET/CT studies were performed in 31 patients. Lesion status was determined on the basis of clinical follow-up including radiological imaging (follow-up CT scan) at least 6 months and response to therapy. RESULTS Of the 35 PET/CT studies, 13 (37%) studies were positive, whereas 22 (63%) of them were negative. On study-based analysis the overall sensitivity, specificity, accuracy for PET/CT imaging were 100%, 96% and 97%, respectively. The corresponding information for CI were 46%, 87% and 74%, for CA 125 (cut off=20U/ml) measurement were 45%, 88% and 74%, and for CA 125 (cut off=35U/ml) measurement were 27%, 100% and 78%, respectively. On lesion-based analysis, PET/CT revealed only one false positive case. In none of 21 patients with negative 22 PET/CT studies, no subsequent clinical or radiological recurrences were observed with a follow-up of at least 6 months. CONCLUSION FDG-PET/CT is found more useful modality than CI and CA 125 in the evaluation of post-treatment endometrial carcinoma patients, for suspected recurrence.

MRI in the diagnosis of Mayer-Rokitansky-Kuster-Hauser syndrome.

PURPOSE The aim of this study was to establish the role of magnetic resonance imaging (MRI) in patients with Mayer-Rokitansky-Kuster-Hauser syndrome (MRKHS). MATERIALS AND METHODS Sixteen female MRKHS patients (mean age, 19.4 years; range, 11-39 years) were studied using MRI. Two experienced radiologists evaluated all the images in consensus to assess the presence or absence of the ovaries, uterus, and vagina. Additional urogenital or vertebral pathologies were also noted. RESULTS Of the 16 patients, complete aplasia of uterus was seen in five patients (31.3%). Uterine hypoplasia or remnant uterus was detected in 11 patients (68.8%). Ovaries were clearly seen in 10 patients (62.5%), and in two of the 10 patients, no descent of ovaries was detected. In five patients, ovaries could not be detected on MRI. In one patient, agenesis of right ovary was seen, and the left ovary was in normal shape. Of the 16 cases, 11 (68.8%) had no other extragenital abnormalities. Additional abnormalities were detected in six patients (37.5%). Two of the six had renal agenesis, and one patient had horseshoe kidney; renal ectopy was detected in two patients, and one patient had urachal remnant. Vertebral abnormalities were detected in two patients; one had L5 posterior fusion defect, bilateral hemisacralization, and rotoscoliosis, and the other had coccygeal vertebral fusion. CONCLUSION MRI is a useful and noninvasive imaging method in the diagnosis and evaluation of patients with MRKHS.

Radiologic findings of thoracic scoliosis due to giant ganglioneuroma

A 28-year-old male with scoliosis presented with complaints of dyspnea and vomiting. His medical history revealed a mediastinal ganglioneuroma resection at the age of 2. After the surgery, he had not been followed up until his admission to our hospital. Computed tomography and MRI showed severe scoliosis of the thoracic spine and a paravertebral mass extending from the upper thoracic level to the level of renal arteries. Based on its radiological findings and the patients history, the tumor was considered to be a recurrent ganglioneuroma. Paravertebral ganglioneuromas may cause progressive scoliosis, and a careful examination for patients with progressive scoliosis is mandatory.

Primary epithelioid trophoblastic tumor with a synchronous breast carcinoma detected only with FDG-PET/CT Scan

Epithelioid trophoblastic tumor is a recently described, rare and distinctive type of gestational trophoblastic tumor. We report the case of a 31-year old patient who had a full-term pregnancy 18 months before presentation. She had a right axillary lymph node metastasis and was referred for FDG-PET/CT scan for evaluation of distant metastasis and to detect primary malignancy. The axillary lymph node biopsy revealed metastatic breast carcinoma. FDG-PET/CT revealed increased uptake of right axillary lymph node, soft tissue density lesion with a diameter of 24 mm on left cervical region with increased FDG uptake, increased uptake on cervical region and left inguinal lymph node with increased uptake. Pelvic MRI imaging and ultrasonography were negative for malignancy in cervical region. Biopsy of the lesion was consistent with epithelioid trophoblastic tumor in cervical region. Gestational trophoblastic tumor was not suspected because she had no signs such as abnormal vaginal bleeding. FDG-PET/CT demonstrated the primary lesion in cervical region. We report a rare case of primary epithelioid trophoblastic tumor detected only with FDG-PET/CT scan which synchronized with breast carcinoma.

Nonodontogenic mandibular lesions: differentiation based on CT attenuation

Mandibular lesions are classified as odontogenic and nonodontogenic based on the cell of origin. Odontogenic lesions are frequently encountered at head and neck imaging. However, several nonodontogenic pathologies may also involve mandible and present further diagnostic dilemma. Awareness of the imaging features of nonodontogenic lesions is crucial in order to guide clinicians in proper patient management. Computed tomography (CT) may provide key information to narrow diagnostic considerations. Nonodontogenic mandibular lesions may have lytic, sclerotic, ground-glass, or mixed lytic and sclerotic appearances on CT. In this article, our aim is to present various nonodontogenic lesions of the mandible by categorizing them according to their attenuations on CT.