Isis Gayed

Does colon cancer ever metastasize to bone first? a temporal analysis of colorectal cancer progression

BackgroundIt is well recognized that colorectal cancer does not frequently metastasize to bone. The aim of this retrospective study was to establish whether colorectal cancer ever bypasses other organs and metastasizes directly to bone and whether the presence of lung lesions is superior to liver as a better predictor of the likelihood and timing of bone metastasis.MethodsWe performed a retrospective analysis on patients with a clinical diagnosis of colon cancer referred for staging using whole-body 18F-FDG PET and CT or PET/CT. We combined PET and CT reports from 252 individuals with information concerning patient history, other imaging modalities, and treatments to analyze disease progression.ResultsNo patient had isolated osseous metastasis at the time of diagnosis, and none developed isolated bone metastasis without other organ involvement during our survey period. It took significantly longer for colorectal cancer patients to develop metastasis to the lungs (23.3 months) or to bone (21.2 months) than to the liver (9.8 months). Conclusion: Metastasis only to bone without other organ involvement in colorectal cancer patients is extremely rare, perhaps more rare than we previously thought. Our findings suggest that resistant metastasis to the lungs predicts potential disease progression to bone in the colorectal cancer population better than liver metastasis does.

A Novel Nomenclature to Classify Parathyroid Adenomas

BackgroundA uniform and reliable description of the exact locations of adenomatous parathyroid glands is necessary for accurate communications between surgeons and other specialists. We developed a nomenclature that provides a precise means of communicating the most frequently encountered parathyroid adenoma locations.MethodsThis classification scheme is based on the anatomic detail provided by imaging and can be used in radiology reports, operative records, and pathology reports. It is based on quadrants and anterior-posterior depth relative to the course of the recurrent laryngeal nerve and the thyroid parenchyma. The system uses the letters A-G to describe exact gland locations.ResultsA type A parathyroid gland is a gland that originates from a superior pedicle, lateral to the recurrent laryngeal nerve compressed within the capsule of the thyroid parenchyma. A type B gland is a superior gland that has fallen posteriorly into the tracheoesophageal groove and is in the same cross-sectional plane as the superior portion of the thyroid parenchyma. A type C gland is a gland that has fallen posteriorly into the tracheoesophageal groove and on a cross-sectional view lies at the level of or below the inferior pole of the thyroid gland. A type D gland lies in the midregion of the posterior surface of the thyroid parenchyma, near the junction of the recurrent laryngeal nerve and the inferior thyroid artery or middle thyroidal vein; because of this location, dissection is difficult. A type E gland is an inferior gland close to the inferior pole of the thyroid parenchyma, lying in the lateral plane with the thyroid parenchyma and anterior half of the trachea. A type F gland is an inferior gland that has descended (fallen) into the thyrothymic ligament or superior thymus; it may appear to be “ectopic” or within the superior mediastinum. An anterior-posterior view shows the type F gland to be anterior to the trachea. A type G gland is a rare, truly intrathyroidal parathyroid gland.ConclusionsA reproducible nomenclature can provide a means of consistent communication about parathyroid adenoma location. If uniformly adopted, it has the potential to reliably communicate exact gland location without lengthy descriptions. This system may be beneficial for surgical planning as well as operative and pathology reporting.

Peritoneal carcinomatosis in patients with ovarian cancer: Enhanced CT versus 18F-FDG PET/CT

Purpose The study aimed to evaluate the efficacy of PET/CT in detecting peritoneal carcinomatosis in patients with ovarian cancer and to compare the diagnostic accuracy of FDG PET/CT with that of enhanced abdominal CT. Methods The medical records of 46 consecutive patients with ovarian cancer were reviewed, and the presence of peritoneal tumor on 18F-FDG PET/CT and enhanced abdominal CT scans was also assessed. Imaging results were compared with the pathologic findings obtained by surgery. Results Pathologic results were positive for peritoneal carcinomatosis in 26 patients and negative in 20 patients. PET/CT correctly detected 25 of 26 patients with peritoneal carcinomatosis and enhanced abdominal CT correctly detected 23 of 26 patients. Sensitivity and specificity for the diagnosis of peritoneal carcinomatosis were 96.2% and 90%, respectively, for PET/CT and 88.5% and 65%, respectively, for enhanced abdominal CT. The accuracy of PET/CT was statistically higher than that of enhanced abdominal CT (93.5% vs 78.3%, P = 0.039). Four distinctly abnormal PET/CT findings of single nodular, multiple nodular, diffuse, and mixed FDG uptakes were identified and corresponded to pathologic findings. Conclusions 18F-FDG PET/CT imaging is efficient in the diagnosis of peritoneal carcinomatosis and its performance is superior to that of enhanced abdominal CT.

Technetium-99m sestamibi uptake in a maxillary brown tumor.

Brown tumors have been reported to take up TI-201 when dual-tracer parathyroid scintigraphy using TI-201 and Tc-99m pertechnetate was performed. With the change to the more favorable Tc-99m sestamibi parathyroid scanning, similar phenomena of tracer uptake in brown tumors have been reported. The authors describe a 44-year-old man with a left maxillary swelling. Laboratory investigations revealed elevated parathyroid hormone levels. Computed tomography of the head showed a left maxillary expansile mass. Subsequently, a Tc-99m sestamibi scan was performed to rule out a parathyroid adenoma. Left inferior parathyroid retention of the tracer was seen, indicating a parathyroid adenoma. An incidental finding was the uptake of Tc-99m MIBI in the left maxillary brown tumor. This case suggests the utility and possible specificity of Tc-99m MIBI uptake in diagnosing brown tumors.

The impact of DaTscan in the diagnosis of Parkinson disease.

Purpose The aim of this study was to evaluate the impact of DaTscan in a heterogeneous group of patients with movement disorders as well as the degree of confidence in scan findings between different readers. Procedures A retrospective evaluation of consecutive patients who underwent DaTscan during 1 year was performed. The patients’ demographics, symptoms, duration, clinical diagnosis, and medications were collected. The scan findings were categorized by 2 blinded observers on a semiquantitative scale as follows: 0, normal; 1, mild; 2, moderate; 3, marked; and 4, absent uptake for each of the caudate heads and putamina separately. A correlation of the scan findings with the clinical symptoms and diagnosis as well as interobserver agreement was performed. Disagreement was considered when a difference greater than 2 in more than 1 area of the basal ganglia was recorded. Descriptive statistics and &kgr; test for interobserver agreement were used for data analysis. Results Fifty-seven patients were included (mean age, 63.4 years; 29 men, 28 women). Clinical diagnosis of Parkinson disease (PD) was certain in 26 and uncertain in 31 patients. DaTscan was markedly abnormal in 24 (92%) of 26 patients with certain clinical diagnosis of PD and normal in the remaining 2 (8%). In 31 patients with uncertain diagnosis, 15 (48%) had markedly abnormal scans, 5 (16%) had mild abnormalities, and 11 (36%) had normal scans. Each of the sensitivity and positive predictive value of DaTscan in patients who had certain clinical diagnosis of PD (26 patients) is 92%. Interobserver agreement occurred in 52 (91%) of 57 scans and disagreement in 5 (9%) of 57 (&kgr; = 0.82). There was also a good correlation with laterality of symptoms in 32 (82%) of 39 positive studies. Conclusions Markedly abnormal DaTscan is confirmed as the diagnostic pattern for PD. This pattern helps confirm the diagnosis in patients with unclear clinical diagnosis. Good interobserver agreement is easily obtained in reading DaTscans.

Timing for repeated treatment of hyperthyroid disease with radioactive iodine after initial treatment failure

Purpose It has been reported that the effect of radioactive iodine (RAI) treatment is complete in 4 to 6 months. This retrospective study evaluated the appropriate time for repeated treatment of hyperthyroid disease with RAI after initial treatment failure. Methods Outcomes of 128 patients treated with RAI for hyperthyroid disease were reviewed retrospectively at 3 and 6 months. Results Eighty patients (group A) were treated successfully with a single dose of RAI. Twenty patients (group B) required a second treatment dose. Twenty-eight patients were lost to follow-up. All patients in group A were clinically improved to various degrees at 3 months and continued to improve at 6 months. All eight patients in group B who showed no improvement at 3 months remained the same at 6 months. The difference between the two groups was statistically significant. Conclusion Patients with hyperthyroid disease who are unimproved at 3 months can be retreated with RAI without further delay.

The value of fused SPECT/CT in the evaluation of solitary skull lesion.

Aim: The aim of this study was to evaluate the role of single photon emission computed tomography and/or computed tomography (SPECT/CT) in differentiating metastatic from benign solitary skull lesions. Materials and Methods: Consecutive patients who had a SPECT/CT of the head subsequent to a whole-body bone scan (WBS) for the evaluation of a single skull lesion were selected. A single skull lesion on the WBS was further evaluated with SPECT/CT to characterize the lesion. The results of the SPECT/CT were correlated with other radiologic examinations performed within 2 weeks. An average follow-up interval after the SPECT/CT was 8.9 months to correlate with additional radiologic imaging studies and clinical information. Results: A total of 19 lesions in 19 patients were seen on the WBS and 2 additional lesions on the SPECT/CT. All lesions demonstrated focal increased tracer uptake. The SPECT/CT correctly identified 3 out of 3 metastatic lesions and 12 out of 17 benign lesions, that is 71% of lesions were correctly classifised as metastatic or benign lesions. Only 1 patient was classified incorrectly as metastatic lesion with SPECT/CT when it was proven benign by other imaging modalities and follow-up. The sensitivity, specificity, positive and negative predictive values of SPECT/CT images in identifying metastatic lesions were 100%, 92%, 75%, and 100%, respectively. Five lesions remained indeterminate even after the SPECT/CT interpretation and were confirmed benign by other imaging modalities. Conclusion: SPECT/CT can help identify benign versus metastatic solitary skull lesions in most of the patients with high sensitivity and specificity.

Intrathoracic splenosis status after a motor vehicle accident

The authors examined a 33-year-old man who was involved in a motor vehicle accident approximately 10 years previously and had sustained significant injuries, including splenic rupture, left diaphragmatic rupture, hemopneumothorax, and left lung collapse. Immediately, the patient was operated on: His spleen was removed and the left diaphragm was repaired. Ten years later, the patient was examined because of a new nonhealing ulcer overlying a right tibial fracture. A Tc-99m-labeled WBC scan was performed to rule out osteomyelitis. Although he had no chest- or abdominal-related complaints, the labeled WBC scan showed multiple foci of intense tracer uptake in the left hemithorax. These foci represent left intrathoracic splenosis after left diaphragmatic rupture. Splenosis is usually seen in the abdomen and pelvis and is unusual in the chest.

Is Iterative Reconstruction an Improvement Over Filtered Back Projection in Processing Gated Myocardial Perfusion SPECT

The impact of iterative reconstruction (IR) on myocardial perfusion imaging (MPI) interpretation and func- tional results is under investigated. We evaluated the effect of IR on the interpretation and functional results of MPI com- pared with filtered back-projection (FBP). Material and Methods: Sixty patients with previously acquired MPI were ran- domly selected. Studies were processed using FBP and 2D ordered-subsets expectation-maximization (OSEM). Two phy- sicians interpreted the images after IR and FBP processing. Results were confirmed by coronary angiography and/or clini- cal course. Left ventricular ejection fraction (LVEF), end-diastolic volume (EDV) and end-systolic volume (ESV) were calculated with IR and FBP. Results: The sensitivity, specificity, positive and negative predictive values and accuracy of physician 1 were 95%, 87%, 80%, 97%, and 90% with FBP and 100%, 80%, 72%, 100%, and 87% with IR. For physician 2, they were 95%, 95%, 91%, 97%, and 95% with FBP and 81%, 95%, 90%, 90%, and 90% with IR. There were no statis- tically significant differences between physicians interpretations (P=0.71 for FBP and 0.09 for IR). There was good cor- relation between IR and FBP calculated LVEF (r=0.98), EDV (r=0.99), and ESV (r=0.99) but significant difference per patient (P=0.02, 0.03 and 0.02, respectively). Conclusion: There is no statistically significant difference in interpretation of MPI with IR versus FBP but there were statistically significant differences in functional results.

False negative Tc-99m hepatobiliary scan in a patient with Osler-Weber- Rendu disease

A 51-year-old woman with Osler-Weber-Rendu disease presented with right upper quadrant pain. Ultrasonography of the gallbladder and Tc-99m cholescintigraphy showed no evidence of acute cholecystitis. CT of the abdomen 9 hours after the hepatobiliary scan was consistent with acute cholecystitis. A gangrenous gallbladder was surgically removed after identification and ligation of an anomalous accessory right hepatic duct inserting directly into the gallbladder. The pathologic examination confirmed the diagnosis of acute ischemic acalculous cholecystitis.