Wonsick Choe

Evaluation of patients with hepatocellular carcinomas using [11C]acetate and [18F]FDG PET/CT: A preliminary study

It is well known that [(18)F]FDG PET has a low sensitivity in the detection of hepatocellular carcinoma (HCC). We prospectively compared [(11)C]acetate PET/CT results with those of [(18)F]FDG PET/CT in patients with HCCs. Thirteen patients (M:F=11:2, mean age of 51+/-12) with suspicious or confirmed HCCs underwent [(11)C]acetate PET/CT with or without [(18)F]FDG PET/CT (both [(11)C]acetate and [(18)F]FDG PET/CT were performed in 10 patients). HCC was confirmed by histopathology or clinical criteria in 12 patients and one benign liver lesion. Both PET/CT images were interpreted by two experienced nuclear physicians, supported by standardized uptake value (SUV). A total of 12 patients were confirmed to have initial or recurrent HCCs. [(18)F]FDG PET/CT showed markedly increased uptake in only two patients, moderately increased uptake in another two and negative in six. [(11)C]acetate PET/CT demonstrated markedly increased uptake in seven patients, moderately increased uptake in three and negative in only two. One HCC metastatic lesion was detected only by [(11)C]acetate PET/CT. For detection of HCC, [(11)C]acetate PET/CT showed a high sensitivity of 83%, whereas [(18)F]FDG PET/CT only of 40%. The study results demonstrated that [(18)F]FDG PET/CT has a limitation in detection of HCC and [(11)C]acetate PET/CT has a complementary role to [(18)F]FDG PET/CT. When primary HCC showed low [(18)F]FDG uptake, it was [(11)C]acetate-avid, and vice versa. It may be useful to combine both [(18)F]FDG and [(11)C]acetate PET/CT for detection of HCCs.

Computer aided diagnosis (CAD) of breast mass on ultrasonography and scintimammography

Both breast ultrasonography (US) and scintimammography (SMM) shows limited diagnostic accuracy in the differential diagnosis of breast cancer. We investigated whether the diagnostic performance of computer-aided diagnosis (CAD) of US was improved by adding SMM results. We retrospectively reviewed 40 breast US images and corresponding SMM images from 40 patients who presented with breast masses (21 malignant and 19 benign tumors). The morphologic features of the breast lesions on US were extracted and quantitated using the automated CAD software program (So no Eye, CAD Impact, Inc., Seoul, Korea), which calculated the probability of malignancy based on the stored database. The quantitative data of SMM were obtained as the uptake ratio of lesion to contralateral normal breast on SMM SPECT. The diagnostic accuracy of CAD of US and SMM was determined using ROC curve analysis, respectively. The best discriminating function combining the CAD results of US and SMM uptake value was created using linear discriminant analysis and the diagnostic performance was compared to that using only one diagnostic modality. Both US and SMM showed a relatively good diagnostic accuracy (area under curve=0.831 and 0.846, respectively). Combining CAD results of US and SMM resulted in improved diagnostic accuracy (area under curve =0.860), but it was not statistically significant. The diagnostic performance of CAD of breast US in the differential diagnosis of the breast mass was not significantly improved by adding SMM. However, SMM SPECT may be complementary to CAD of US in differential diagnosis of breast cancer.

F-18 Fdg Pet/ct Findings in a Case of Undifferentiated Embryonal Sarcoma of the Liver With Lung and Adrenal Gland Metastasis in a Child

Abstract: A 7-year-old boy presented with an undifferentiated embryonal sarcoma of the liver (UESL), which is a rare pediatric neoplasm that originates from the mesenchyme. F-18 FDG PET/CT associated with a separately acquired contrast-enhanced CT was performed to evaluate the status of the tumor during postoperative chemotherapy, which followed the initial neoadjuvant chemotherapy (vincristine, cisplatin, adriamycin, cyclophosphamide, and actinomycin-D) and radical tumor resection. Evaluation of the F-18 FDG PET/CT demonstrated the presence of a highly metabolic lesion in the liver (primary site) and the presence of distinct foci of FDG uptake as a result of tumor metastases, with 3 foci being observed in both lungs and one being observed in the right adrenal gland. This case gives a suggestion that F-18 FDG PET/CT can be valuable method for evaluation of the status of UESL.

Imaging seminal vesiculitis with Tc-99m ciprofloxacin.

The authors describe Tc-99m ciprofloxacin SPECT imaging and corresponding magnetic resonance images (MRIs) of a patient with a prostatitis syndrome, in whom seminal vesiculitis was finally diagnosed. Tc-99m ciprofloxacin imaging can detect areas of active bacterial infection. It is difficult to accurately classify patients with a prostatitis syndrome, because valid diagnostic tests are rare and the treatment is often empirical. Visualization of acute seminal vesiculitis in patients with a prostatitis syndrome, made possible with Tc-99m ciprofloxacin imaging, should improve diagnostic accuracy.

Sesamoids opened earlier and easier by bone imaging.

A 20-year-old woman who was a tennis player underwent three-phase bone imaging to rule out fracture in the right foot. She complained of pain in the region of the first digit, but x-rays did not show any changes. Bone imaging showed increased bilateral uptake in the sesamoids of the great toes on blood pool and delayed images. It was thought that the findings were suggestive of sesamoiditis or stress to the sesamoids.

Pelvic inflammatory disease with Tc-99m Ciprofloxacin imaging

The clinical diagnosis of pelvic inflammatory disease (PID) is inexact. There are multiple potential symptoms and signs ascribable to PID as predicted by areas of inflammatory involvement. No symptoms or signs are pathognomonic for PID. The authors describe single photon emission computed tomography (SPECT) images of technetium‐99m (99mTc) ciprofloxacin imaging of patients with PID that showed foci of significantly increased uptake in the regions corresponding to the areas of clinical symptoms. We report two such cases of PID. We undertook physical exams, complete blood count, erythrocyte sedimentation rate, C‐reactive protein, Gram stains, wet smears, cultures, Mycoplasma genetic studies, Chlamydia cultures, and SPECT before treatment. During treatment we took laparoscopies, hysteroscopies, biopsies, and cultures. After the treatment, we repeated the same exams. 99mTc ciprofloxacin imaging is considered valuable in persons with symptoms of PID in whom diagnosis is difficult.

Tc-99m MDP uptake in an old surgical scar mimicking an anomalous ureter.

Bone imaging was performed for metastatic investigation on a 68-year-old man with prostate and rectal cancer. The image showed no evidence of bony metastasis. Interestingly, however, there was linear increased uptake apparently following the course of the left ureter and ending on the right side of the urinary bladder. According to the authors search in the literature, no report was found that addressed a crossed ureter with two kidneys. The patient had a resection of a rectal tumor 4 years earlier and abdominoperitoneal resection of recurrent tumor 2 years earlier. On physical examination, the patients surgical scar on the abdomen ran the same course as the increased uptake.

Is this Red Spot the Blue Spot (locus ceruleus)

The authors report brain images of 18F-FDG-PET in a case of schizophrenia. The images showed strikingly increased bilateral uptake in the locus ceruleus. The locus ceruleus is called the blue spot and known to be a center of the norepinephrinergic system.

Quiescent and painful accessory navicular bones in the same patient.

A 35-year-old woman underwent bone imaging to evaluate progressive pain over the medial aspect of her right foot. She was a homemaker and had not sustained any recent trauma to the region. The images showed a focus of increased uptake in the right medial midfoot. Simultaneously obtained radiographs showed the accessory ossicles adjacent to the navicular bones bilaterally. This indicated that she had right inflammatory and left quiescent accessory navicular ossicles at the same time. Bone imaging functioned well as a diagnostic method in differentiating them.

Site of Mistletoe Injection Observed on In-111 OncoScint Imaging

In-111 satumomab pendetide (Cytogen Corp., Princeton, NJ) (OncoScint CR/OV) planar imaging was performed to detect recurrence of colorectal cancer in an 81-year-old woman. Imaging showed no evidence of recurrence. However, an area of increased uptake was noted in the left thigh. When she was questioned, the patient admitted that she had self-injected a privately imported medicine intramuscularly to that area. The active ingredient was mistletoe, that she believed would cure the colorectal cancer.