Prospective Randomized Trial of Use of In-House Prepared Low-Cost Radiopharmaceutical Versus Commercial Radiopharmaceutical for Sentinel Lymph Node Biopsy in Patients with Early Stage Invasive Breast Cancer.

BACKGROUND: The current standard-of-care for surgical staging of the axilla in clinically node-negative (N0) early breast cancers is sentinel lymph node biopsy (SLNB), which requires expensive radiopharmaceuticals for efficacious results. In-house produced low-cost radiopharmaceuticals may be the solution and have shown efficacy in earlier observational/pilot studies. We compared SLNB using in-house prepared radiopharmaceutical (99mTc-Antimony-colloid) versus commercially marketed radiopharmaceutical (99mTc-Sulphur-colloid) in this prospective randomized study. STUDY DESIGN: 78 clinically N0 early breast cancer patients (T1/2, N0 stages), undergoing primary surgery were prospectively randomized 1:1 into two groups; to receive SLNB using methylene blue, and either 99mTc-Antimony colloid (Group-1) or  99mTc-Sulphur colloid (Group-2). Completion axillary dissection was done in all (validation SLNB). SLNB indices were compared between the groups. RESULTS: The groups were comparable with regard to age, stage, tumour size, hormone receptors and HER2neu status. Cost of the in-house prepared 99mTc-antimony colloid was 16-times lesser compared to 99mTc-sulphur colloid. SLN identification rates (IR) in Groups 1 and 2 were 100 and 97.4% respectively, (p > 0.05). False negative rates (FNR) in Group 1 and 2 were 6.3% (1/16 patients) and 7.7% (1/13 patients), respectively, (p > 0.05). There were no major allergic reactions in either group. CONCLUSION: In this prospective randomized trial on early breast cancer patients, accuracy of SLNB was comparable using in-house prepared, 99mTc-antimony colloid and commercially marketed 99mTc-sulphur colloid as radiopharmaceutical, while 99mTc-antimony colloid was much cheaper than 99mTc-sulphur colloid.

Assessment of Spleen Filtrate Function in Renal Transplant Recipients Using Technetium-99m Stannous Colloid Liver-Spleen Scan.

BACKGROUND: Functional hyposplenism (FH) is indicated by an anatomically present spleen that fails to take up radiolabeled colloid. The occurrence of FH has been reported in a small group of renal transplant recipients based on hematologic parameters. The aim of this study was to replicate this association in a larger group of renal transplant recipients with the use of technetium-99m-stannous colloid liver-spleen scan to assess the spleen function. METHODS: This survey based on single samples enrolled 101 unselected adult patients with functional kidney grafts >180 days after transplantation. All patients underwent 99mTc-stannous colloid scan to assess spleen function as well as bone marrow uptake of radiocolloid along with an anatomic and blood flow study of the spleen and kidney with the use of Doppler sonography. RESULTS: The prevalence of hyposplenism was 32.7% (33/101) for the cohort, and increased uptake of radiocolloid by the bone marrow was seen in 9.9% (10/101). According to the multivariate analysis, the frequency of hyposplenism was significantly influenced by indirect bilirubin and hemoglobin, and direct bilirubin and neutrophil count remained as independent predictors of bone marrow uptake. CONCLUSIONS: This study demonstrated that a group of renal transplant recipients has FH. In addition, bone marrow uptake might be interpreted as liver dysfunction. In this situation, the small amount of contrast (spleen compared with liver) would leave hyposplenism undiagnosed. Further prospective and longitudinal clinical studies are needed to determine the clinical impact of this condition on the management of renal transplant recipients.

Cost analysis of sentinel lymph node biopsy in melanoma.

INTRODUCTION AND OBJECTIVE: Sentinel lymph node biopsy (SLNB) is the most useful tool for node staging in melanoma. SLNB facilitates selective dissection of lymph nodes, that is, the performance of lymphadenectomy only in patients with sentinel nodes positive for metastasis. Our aim was to assess the cost of SLNB, given that this procedure has become the standard of care for patients with melanoma and must be performed whenever patients are to be enrolled in clinical trials. Furthermore, the literature on the economic impact of SLNB in Spain is scarce. METHOD: From 2007 to 2010, we prospectively collected data for 100 patients undergoing SLNB followed by transhilar bivalving and multiple-level sectioning of the node for histology. Our estimation of the cost of the technique was based on official pricing and fee schedules for the Spanish region of Murcia. RESULTS: The rate of node-positive cases in our series was 20%, and the mean number of nodes biopsied was 1.96; 44% of the patients in the series had thin melanomas. The total cost was estimated at between €9486.57 and €10471.29. Histopathology accounted for a considerable portion of the cost (€5769.36). DISCUSSION: The cost of SLNB is high, consistent with amounts described for a US setting. Optimal use of SLNB will come with the increasingly appropriate selection of patients who should undergo the procedure and the standardization of a protocol for histopathologic evaluation that is both sensitive and easy to perform.

Nuclear medicine and molecular imaging of the pediatric chest: current practical imaging assessment.

In the chest, the indications for nuclear medicine studies are broader and more varied in children than in adults. In children, nuclear medicine studies are used to evaluate congenital and developmental disorders of the chest, as well as diseases more typical of adults. In the chest, pediatric nuclear medicine uses the same radiopharmaceuticals and imaging techniques as used in adults to evaluate cardiac and pulmonary disease, aerodigestive disorders, and pediatric malignancies. The introduction of PET (mostly using (18)F-FDG) has transformed pediatric nuclear oncology, particular for imaging malignancies in the chest.

The role of selective sentinel lymph node dissection in breast cancer.

Axillary nodal status continues to be the most statistically significant predictor of survival for patients with breast cancer. Although still providing regional control of axillary disease, axillary dissection is more important as a staging and prognostic tool. Trials are currently underway to investigate the possibility of replacing the current standard treatment of breast cancer, axillary lymph node dissection, with the less invasive lymphatic mapping and sentinel lymph node biopsy. This issue and the technical aspects of sentinel lymph node mapping for breast cancer are discussed in detail in this article.

[Radionuclide scan with TC-99m-tin colloid in the evaluation of orthopedic implant infections]. / Gammagrafía con 99mTc-coloide de estaño en la valoración de la infección de los implantes ortopédicos.

We have studied 26 patients (32-77 years old, 16 females) with suspicion of joint arthroplasty infection: 11 total hip replacements, 12 total knee replacements and 3 osteosinthesys. A bone scintigraphy with MDP-99mTc, a scintigraphy with HMPAO-WBC and a scintigraphy with 99mTc-stannous colloid were made in all patients. The final diagnostic was based in joint cultures and clinic and radiologic evolution of the patients. The earliest phase of the bone scintigraphy was positive in 18 patients. The later phase was positive in all them. The WBC was positive in 20 out of 26 patients. The bone marrow scintigraphy showed a congruent pattern with WBC in 18 patients (17 infected and 1 without infection). The other ones (8 patients) showed an incongruent pattern (7 with infection and 1 without it). The results show that the bone marrow scintigraphy with 99mTc-stannous colloid improves the accuracy of the diagnostic of bone prosthesis infection and should be included into the diagnosis protocol of this disease.

A Monte Carlo investigation of artifacts caused by liver uptake in single-photon emission computed tomography perfusion imaging with technetium 99m-labeled agents.

BACKGROUND: Significant hepatobiliary accumulation of technetium 99m-labeled cardiac perfusion agents has been shown to cause alterations in the apparent localization of the agents in the cardiac walls. A Monte Carlo study was conducted to investigate the hypothesis that the cardiac count changes are due to the inconsistencies in the projection data input to reconstruction, and that correction of the causes of these inconsistencies before reconstruction, or including knowledge of the physics underlying them in the reconstruction algorithm, would virtually eliminate these artifacts. METHODS AND RESULTS: The SIMIND Monte Carlo package was used to simulate 64 x 64 pixel projection images at 128 angles of the three-dimensional mathematical cardiac-torso (MCAT) phantom. Simulations were made of (1) a point source in the liver, (2) cardiac activity only, and (3) hepatic activity only. The planar projections and reconstructed point spread functions (PSFs) of the point source in the liver were investigated to study the nature of the inconsistencies introduced into the projections by imaging, and how these affect the distribution of counts in the reconstructed slices. Bull's eye polar maps of the counts at the center of the left ventricular wall of filtered back-projection (FBP) and maximum-likelihood expectation-maximization (MLEM) reconstructions of projections with solely cardiac activity, and with cardiac activity plus hepatic activity scaled to have twice the cardiac concentration, were compared to determine the magnitude and location of apparent changes in cardiac activity when hepatic activity is present. Separate simulations were made to allow the investigation of stationary spatial resolution, distance-dependent spatial resolution, attenuation, and scatter. The point source projections showed significant inconsistencies as a function of projection angle with the largest effect being caused by attenuation. When consistent projections were simulated, no significant impact of hepatic activity on cardiac counts was noted with FBP, or 100 iterations of MLEM. With inconsistent projections, reconstruction of 180 degrees resulted in greater apparent cardiac count losses than did 360 degrees reconstruction for both FBP and MLEM. The incorporation of attenuation correction in MLEM reconstruction reduced the changes in cardiac counts to that seen in simulations in which attenuation was not included, but resulted in increased apparent localization of activity in the posterior wall of the left ventricle when scatter was present in the simulated images. CONCLUSIONS: The apparent alterations in cardiac counts when significant hepatic localization is present is due to the inconsistency of the projections inherent in imaging. Prior correction of these, or accounting for them in the reconstruction algorithm, will virtually eliminate them as causes of artifactual changes in localization. Attenuation correction and scatter correction are both required to overcome the major sources of apparent count changes in the heart associated with hepatic uptake.

Assessment of the effects of aging and medication on salivary gland function in patients with xerostomia using 99mTC-scintigraphy.

To examine the effect of aging and medication on xerostomia, the salivary gland function was evaluated in 20 patients with xerostomia using 99mTc-scintigraphy and the measurement of unstimulated whole saliva (USWS). All of the patients showed USWS volume of less than 2ml/10min. The patients were divided into 2 subgroups based on age (under 65 and 65 and older) and medication status (patients who were on medication which reduced salivary secretion and patients who were not on such medication). The scintigraphic results, such as the maximum radioisotope (RI) count, RI secretion velocity and the volume of USWS, were compared between the subgroups. The maximum RI count and the RI secretory velocity in the submandibular gland and the volume of USWS revealed significantly different functional disturbances between relatively younger patients (under 65) and older patients (65 and older). There was no difference when the scintigraphic results and the volume of USWS measurements in medicated patients were compared with the results of similar tests performed on non-medicated patients. When the medicated and non-medicated groups were separated by age, an increase in age still diminished the volume of USWS in medicated patients. This result might be related to an organic change in the submandibular gland in older patients which was suggested by the scintigraphic results.

Assessment of the brain areas perfused by superselective intra-arterial chemotherapy using single photon emission computed tomography with technetium-99m-hexamethyl-propyleneamine oxime--technical note.

The brain areas perfused by superselective intra-arterial (i.a.) chemotherapy were assessed using single photon emission computed tomography (SPECT) with technetium-99m-hexamethyl-propyleneamine oxime (99mTc-HMPAO). A superselective catheter was introduced into the anterior, middle, or posterior cerebral artery of patients with malignant glioma for i.a. chemotherapy. 99mTc-HMPAO was subsequently injected via the same catheter used for chemotherapy, and a higher dose of 99mTc-HMPAO was injected intravenously to obtain adequate background brain images. Comparison of the SPECT images with magnetic resonance images could confirm complete perfusion of the tumor tissue. In two patients with malignant glioma, regions of interest were selected in the peritumoral brain area and a reference brain area, and the radioactivity was measured. The concentration of 99mTc-HMPAO was about 50 times higher in tissue perfused by superselective injection into anterior or middle cerebral artery compared to intravenous injection. 99mTc-HMPAO SPECT is readily available in many institutions and the information provided is useful for planning more effective and safe i.a. chemotherapy.

Radionuclide arthrography and transmission imaging for assessment of painful hip prostheses.

UNLABELLED: Interpretation of the radionuclide hip arthrogram may present difficulty because of a lack of anatomical reference information. Additional transmission images to determine tracer localization may facilitate scan interpretation. METHODS: Isotope arthrography (20 MBq 99mTc-tin colloid and 57Co transmission imaging) was prospectively performed on 21 patients with painful hip prostheses and suspected stem loosening. RESULTS: The radionuclide arthrogram was positive in 10 patients and negative in 9 patients. Extravasation of tracer, confirmed by transmission images, resulted in two nondiagnostic studies. Surgery was undertaken in 10 patients and loosening was confirmed in 6 patients. In this surgical subgroup, the scan was true-positive in six patients, true-negative in two patients, false-positive in one patient and nondiagnostic in one patient. CONCLUSIONS: The combination of radionuclide arthrography and transmission imaging facilitates scan interpretation and is a recommended method for investigating suspected loosening of the femoral stem.

Porous-coated acetabular component. Quantitative assessment of normal radiophosphate uptake as a function of implant age.

A computer-assisted quantitative analysis was undertaken of normal radiophosphate bone uptake adjacent to the porous-coated acetabular component in asymptomatic patients. Implants ranged from 1.6 to 49 months of age. In 62 hips, it was found that implants newer than 12 months of age had uptakes that were significantly greater than those 12 months or older. Between 12 and 49 months, there was no correlation with age, indicating a stabilization of the remodeling process.

Arteriovenous shunting of microspheres in patients with colorectal liver metastases: errors in assessment due to free pertechnetate, and the effect of angiotensin II.

In patients receiving locoregional therapy for liver metastases degradable microspheres are being increasingly used in an attempt to improve cytotoxic delivery to the tumour. However, counterproductive arteriovenous shunting through the liver following intrahepatic arterial injection can occur, leading to deposition in the lung. Measurement of the degree of shunting is important in the monitoring of this kind of therapy. In this study we describe the use of technetium-labelled microspheres of serum albumin (99Tcm MSA) to measure baseline shunting during hepatic arterial perfusion scintigraphy in five patients with liver metastases of colorectal origin, and assess the significance of the values obtained for relative lung uptake (RLU) which we define as: RLU = Activity in lung field/Activity in liver + lung fields X 100%. We found that shunting was less than 5% in all cases, zero shunting occurring in 14 of the 16 patients studied. The sources of error in this technique have been assessed, the most important being the presence of free pertechnetate in the injectate. The use of Boots 10 ml vials and glass syringes respectively to dispense and administer this radiopharmaceutical reduces this error to a small predictable level. In our small group of patients, we found no evidence to suggest that use of the vasoactive agent angiotensin II significantly increases baseline shunting in patients with colorectal liver tumour.

The value of lymphoscintigraphy, lymphangiography and computer tomography scanning in the preoperative assessment of lymph nodes involved by pelvic malignant conditions.

In a preoperative study to identify accurately metastases to the lymph nodes within the pelvis and retroperitoneum, the three imaging techniques of pelvic interstitial lymphoscintigraphy, bipedal lymphangiography and computer tomography (CT) scanning were compared in 69 patients with carcinoma of the cervix uteri or rectum. Results were correlated with histologic node examination in all patients and each technique was assessed for sensitivity, specificity and over-all accuracy. Lymphoscintigraphy is too unreliable for routine use in the diagnosis or staging of pelvic malignant conditions. Lymphangiography detects involved lateral pelvic and para-aortic nodes but is unable to visualize the internal iliac or other medial pelvic nodes. CT scanning is only accurate if metastatic nodes are enlarged but may reveal other pathways of spread which will alter the surgical approach.

Frozen shoulder: an arthrographic and radionuclear scan assessment.

The diagnostic criteria and nomenclature used to describe the painful stiff shoulder remain confused. Arthrographic features of capsulitis have come to be accepted as characteristic of the frozen shoulder. Increased technetium uptake has also been noted. Both features have been considered to have possible prognostic and therapeutic importance. During a therapeutic study of strictly defined clinical frozen shoulder 35 of 38 patients showed increased technetium diphosphonate uptake in the affected shoulder in comparison with the opposite side. Of 36 patients who had arthrography 15 showed evidence of capsulitis, 11 rupture of the rotator cuff, and five no abnormality. Five tests failed owing to technical difficulty. There was no association between the technetium uptake and the arthrographic features, and neither was useful in predicting the rate or extent of recovery. Frozen shoulder of traumatic onset behaved no differently from that which arose spontaneously. We do not therefore consider that arthrography or technetium diphosphonate scanning performed at presentation contributes to the assessment of the painful stiff shoulder.