[Drug monitoring].
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Adverse Drug Reaction Reporting Systems↗
Biomedical subjects
J C Roos
Publications and source records attributed to J C Roos.
[Post-marketing surveillance].
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Drug Industry↗
Computed tomography and granulocyte scintigraphy in active inflammatory bowel disease. Comparison with endoscopy and operative findings.
The accuracy of computed tomography (CT) and [99mTc]HMPAO granulocyte scintigraphy (GS) for detection of bowel localization, inflammatory activity, and complications in acute inflammatory bowel disease (IBD) was prospectively studied in 32 patients. Of each bowel segment, findings on CT and GS were scored by one blinded observer. Findings on operation or endoscopy served as the gold standard. In Crohn's disease (CD, 17 patients), CT detected bowel pathology (sensitivity 71%, specificity 98%), abscesses (sensitivity and specificity 100%), and fistulas (sensitivity 80%, specificity 100%). In CD, GS had a sensitive of 79% and a specificity of 98% for detection of inflammatory activity. The detection of complications with GS was poor. Segmental inflammatory activity correlated with endoscopy-operative findings for CT (r = 0/86, P < 0.0001) and GS (r = 0.86, P < 0.0001). In ulcerative colitis (UC, 15 patients), GS predicted proximal extension of bowel involvement better than CT. In CD, CT is Superior to GS for localization of both active and fibrostenotic bowel disease, and in detection of the abscesses and fistulas. In UC, GS showed proximal extension more accurately than CT.
Acute Disease↗
Two-step gonadotropin-releasing hormone agonist treatment of uterine leiomyomas: standard-dose therapy followed by reduced-dose therapy.
OBJECTIVE: Gonadotropin-releasing hormone agonist-induced partial pituitary suppression with low-grade estrogen production may be useful in long-term treatment of uterine leiomyomas. STUDY DESIGN: Twenty-seven women with uterine leiomyomas were treated with a standard dose of triptorelin for 8 weeks. Patients were then randomized to use 100, 20, or 5 micrograms of triptorelin until week 26. Uterine and myoma size, pituitary-ovarian function, bone metabolism, and bone mineral density were monitored. RESULTS: During standard treatment uterine size was reduced to 67.1% of baseline. During randomized treatment uterine size was further reduced to 57.8% of baseline. There were no differences in overall volume reduction among the groups. Luteinizing hormone and estradiol levels were restored in a dose-dependent way. Bone mineral density decreased significantly in the highest-dose group at week 26. CONCLUSIONS: This study shows that the beneficial effects of initial high-dose agonist treatment on uterine leiomyomas can be preserved by continued low-dose treatment. Bone mineral density does not seem to change during reduced-dose agonist treatment.
Adult↗
Tumor uptake of intravenously administered radiolabeled antibodies in ovarian carcinoma patients in relation to antigen expression and other tumor characteristics.
To study factors that possibly influence the heterogeneous tumor uptake of radiolabeled antibodies, tissues from 34 ovarian-carcinoma patients were obtained 2 to 8 days after i.v. injection with radiolabeled murine OV-TL3 or chimeric MOv18 (cMOv18). The tumor uptake and the ratio of tumor to normal tissue (T/NT) were studied in relation to the histopathological classification, prior treatment, site of tumor, time interval, antigen expression, volume percentage of (malignant) epithelium in the tumor tissue, and the size of the tumor. The results of immunoscintigraphy were also included. In addition, autoradiography using storage phosphor technology was performed on tissue sections from patients injected with iodine-labeled cMOv18. Tumor uptake varied largely, not only between patients, but also between tumor deposits within the same patient. Uptake of OV-TL3 F(ab')2 was higher than of cMOv18 F(ab')2, but the T/NT ratios were similar. The antibody uptake was positively correlated with the pattern of antigen expression and inversely correlated with the time interval between injection and surgery. No correlation was observed with any of the other factors studied. The visibility with immunoscintigraphy was related to the size of the detected lesion, but not to the other factors studied. Autoradiography showed that antibodies preferentially localized in areas with cancer cells, which were immunohistochemically positive for MOv18. In areas with weak antigen expression, autoradiography revealed less activity. The antigen expression by the tumor is an important factor for estimation of the tumor uptake of radiolabeled antibodies.
Antibodies, Monoclonal↗
Vitamin D status and sex hormone binding globulin: determinants of bone turnover and bone mineral density in elderly women.
To examine the relation of the vitamin D status and the remaining estrogen activity with bone turnover and bone mineral density (BMD) in elderly women, BMD was measured at both hips using dual-energy X-ray absorptiometry and at the distal radius using single photon absorptiometry, in 330 healthy women aged 70 and over. Vitamin D metabolites, sex hormone binding globulin (SHBG), PTH(1-84), osteocalcin, alkaline phosphatase, and hydroxyproline and calcium excretion in 2 h fasting urine were measured. Multiple linear regression was used to adjust for potential confounders. In 65% of the women, serum 25(OH)D was below 30 nmol/l. Only values below a threshold for 25(OH)D were negatively related to serum PTH(1-84) (p = 0.02, threshold at 25 nmol/l) and to osteocalcin levels (p = 0.04, threshold at 30 nmol/l). BMD of the femoral neck and trochanter was positively related to serum 25(OH)D (left neck p = 0.001) with thresholds at 30 nmol/l whereas the distal radius was not (p = 0.32). Serum PTH was negatively related to BMD at all measurement sites (all p < 0.001). Serum SHBG, an inverse measure of estrogen activity, was positively related to osteocalcin levels (p = 0.004) and the urinary hydroxyproline/creatinine ratio (p = 0.002) and negatively related to the BMD of the trochanter (left trochanter p = 0.02) and the distal radius (p = 0.001). We conclude that in elderly women, serum 25(OH)D levels below 30 nmol/l are associated with secondary hyperparathyroidism and increased bone turnover. SHBG is positively related to bone turnover.(ABSTRACT TRUNCATED AT 250 WORDS)
Absorptiometry, Photon↗
Prevention of bone loss by vitamin D supplementation in elderly women: a randomized double-blind trial.
The purpose of the study was to determine the effect of vitamin D supplementation on bone turnover and bone loss in elderly women. Three hundred forty-eight women, ages 70 yr and older, were randomized to receive 400 IU vitamin D3 per day (n = 177) or placebo (n = 171), double-blind, for a period of 2 yr. Main outcome measures were bone mineral density of both hips (femoral neck and trochanter) and the distal radius, as well as biochemical markers of bone turnover. The effect of vitamin D supplementation was expressed as the difference in mean (percentage) change between the placebo group and the vitamin D group. The measurements were repeated in 283 women after 1 yr and in 248 women after 2 yr. Vitamin D supplementation significantly increased serum 25-hydroxyvitamin D (250HD) (+35 nmol/L) and 1,25-dehydroxyvitamin D [1,25-(OH)2D] (+7.0 pmol/L) levels and urinary calcium/creatinine ratios (+0.5%) and significantly decreased PTH(1-84) secretion (-0.74 pmol/L) after 1 yr. No effect was found for the parameters of bone turnover. The effect on the bone mineral density of the left femoral neck was +1.8% in the first yr, +0.2% in the second yr, and +1.9% during the whole period (95% confidence interval 0.4, 3.4%). At the right femoral neck the effects were +1.5%, +1.1%, and +2.6% (confidence interval 1.1, 4.0%), respectively. No effect was found at the femoral trochanter and the distal radius. Supplementation with 400 IU vitamin D3 daily in elderly women slightly decreases PTH secretion and increases bone mineral density at the femoral neck.
Aged↗
Technetium-99m-sestamibi/thallium-201 mismatch of thyroid and parathyroid adenoma in chronic renal failure.
We report on a patient who had chronic renal failure and relapse of secondary hyperparathyroidism after earlier extirpation of three glands. Whereas 201Tl-chloride uptake was absent in the thyroid and an ectopic parathyroid adenoma during routine subtraction 201Tl-99mTc scintigraphy, both glands could be visualized with 99mTc-sestamibi and [123I]sodium.
Adenoma↗
Biodistribution of radiolabeled monoclonal antibody E48 IgG and F(ab')2 in patients with head and neck cancer.
Biodistribution and pharmacokinetics of radiolabeled mAb E48 IgG and E48 F(ab')2 were analyzed and compared in 39 patients with histologically proven squamous cell carcinoma of the head and neck who were included in a radioimmunoscintigraphy study and underwent surgery 44 h after injection. Three groups of patients were distinguished: group 1 (n = 19) received technetium-99m (99mTc)-labeled E48 F(ab')2, group 2 (n = 9) received 99mTc-labeled E48 IgG, and group 3 (n = 11) received 99mTc- and 131I-labeled E48 IgG as well as 125I-labeled F(ab')2. Two patients in group 1 and four patients in group 3 received a high mAb dose (10-50 mg), while all other patients received a low mAb dose (1-4 mg). From all patients in groups 2 and 3 biopsies from the surgical specimen were obtained 44 h postinjection. Tumor uptake of 99mTc-labeled E48 IgG was high, ranging from 0.007 to 0.082% of the injected dose/g, with a mean of 0.031 +/- 0.020% of the injected dose/g. The mean tumor:nontumor ratio of this conjugate was 2.8 for mucosa, 4.6 for bone marrow aspirate, 4.1 for blood, 20.3 for fat, and 21.0 for muscle. Activity uptake in tumor positive lymph nodes was 4.7 times higher as compared to negative lymph nodes. Sixteen h postinjection radioimmunoscintigraphy revealed activity uptake in the primary tumor, lymph node metastases, oral cavity, and adrenal glands. Using regions of interest, the uptake in the adrenal glands was estimated to be 0.050% of the injected dose/g. If a high mAb dose was used, no adrenal glands were visualized and the uptake in the oral cavity was clearly diminished, while the tumor uptake and tumor:nontumor ratios were increased. The mean elimination half-lifes t1/2 alpha and t1/2 in plasma were: for E48 IgG (n = 20) 6.6 +/- 2.6 and 54.1 +/- 24.3 h and for E48 F(ab')2 (n = 19) 2.3 +/- 0.4 and 19.9 +/- 4.6 h, respectively. Tumor uptake of 131I-labeled E48 IgG was 49% higher than of 125I-labeled F(ab')2. For most tissues except normal oral mucosa, tumor:nontumor ratios were slightly higher for F(ab')2 than for IgG. The present study shows that mAb E48 accumulates selectively and to a high level in head and neck squamous cell carcinoma. Although no definite conclusions can be drawn as to which mAb form is more suitable, IgG or F(ab')2, mAb E48 seems to have potential for radioimmunotherapy in head and neck squamous cell carcinoma patients.
Adrenal Glands↗
Radioimmunoscintigraphy and biodistribution of technetium-99m-labeled monoclonal antibody U36 in patients with head and neck cancer.
So far, mAb E48 is the most promising antibody described for specific targeting of head and neck squamous cell carcinoma (HNSCC) in patients. On the basis of its more homogeneous reactivity pattern on HNSCC, the novel mAb U36 may be even better suited for targeting. In this study the biodistribution of mAb U36 was evaluated by radioimmunoscintigraphy (RIS) and biopsy measurements in 10 patients who were suspected of having neck lymph node metastases from a histologically proven HNSCC and who had been scheduled to undergo resection of the primary tumor and neck dissection. Patients received 1.8-53.0 mg mAb U36 IgG labeled with 756 +/- 95 MBq technetium-99m i.v. Preoperatively, palpation, computerized tomography, magnetic resonance imaging, and RIS were performed. RIS images included planar and single-photon emission computerized tomography images of the head and neck and planar images of the whole body. The diagnostic findings were recorded per side as well as per lymph node level of the neck and compared to the histopathological outcome. Radioactivity in blood samples and biopsies from the surgical specimens were measured. All 10 primary tumors were visualized by RIS. All diagnostic modalities were correct in 7 of 14 tumor-involved lymph node levels. The missed lymph node metastases comprised micrometastases, small tumor-involved nodes (<9 mm), and tumor-involved nodes with much necrosis, keratin, or fibrin. There were no false-positive observations with mAb U36. Besides activity uptake in tumor tissue, only a slight accumulation of activity was observed in the mouth, lungs, liver, spleen, kidneys, and scrotal area. Biopsies from the surgical specimen showed a high tumor uptake of 20.4 +/- 12.4% of the injected dose/kg (range, 8.0-43.0% of injected dose/kg), 44 h postinjection. An increase in the mAb dose did not influence uptake of activity in tumor tissue. The mean tumor:nontumor ratio at this time point was 2.3 for mucosa, 2.8 for blood, 3.0 for bone marrow aspirate, 12.9 for fat, and 13.0 for muscle tissue. The present clinical study shows that technetium-99m-labeled U36 IgG accumulates selectively and to a high level in HNSCC. The tumor-targeting results for U36 IgG are comparable to those previously described for E48 IgG. On the basis of the results of ongoing biodistribution studies in which both mAbs E48 and U36, labeled with different iodine isotopes, are simultaneously evaluated for tumor uptake and retention in HNSCC patients, one of these mAbs will be selected for future adjuvant radioimmunotherapy trials.
Aged↗
A dosimetric model for intrathecal treatment with 131I and 67Ga.
PURPOSE: Calculations were performed of absorbed dose distributions of the beta-emitter 131I and the Auger emitter 67Ga for intrathecal administration. METHODS AND MATERIALS: The proposed dosimetric model accounts for the macroscopic distribution of the activity, by means of a Medical Internal Radiation Dose Committee approach, and for the microscopic distribution of activity, by means of a point kernel technique. This point kernel approach was used in combination with a distance histogram technique, to study in more detail the absorbed dose distribution in the cerebro-spinal fluid, in the surface of the central nervous system, and in tumor sites. We simulated decreased uptake, as well as highly selective uptake in free-floating tumor cells and in meningeal lesions (1-16 cells thick). RESULTS: In case of limited access to lesions adherent to the pia mater, the beta-emitter 131I provides crossfire from the CSF, resulting in a higher absorbed dose (Gy/MBq) in these lesions as compared with the Auger emitter 67Ga. In case of increasing radionuclide uptake, the increment of the absorbed dose in the adherent lesions and the free floating cells from 67Ga is considerable because of the local deposition of energy by this radionuclide. CONCLUSIONS: The model might be useful to select the optimal emission characteristics of radionuclides applicable for intrathecal therapy, which is demonstrated in a comparison of the Auger emitter 67Ga and the beta-emitter 131I.
Gallium Radioisotopes↗
Comparison of non-invasive approaches to red marrow dosimetry for radiolabelled monoclonal antibodies.
Red marrow is usually the dose-limiting organ during radioimmunotherapy. Several non-invasive approaches to calculate the red marrow dose have been proposed. We compared four approaches to analyse the differences in calculated red marrow doses. The data were obtained from immunoscintigraphy of two antibodies with different red marrow kinetics [iodine-131-16.88 IgM and indium-111-OV-TL-3 F(ab')2]. The approaches are based on, respectively, homogeneously distributed activity in the body, a red marrow-blood activity concentration ratio of 0.3, scintigraphic quantification, and a combination of the second and third approaches. This fourth approach may be more adequate because of its independence from the chosen antibody. In addition, the influence of activity accumulation in liver, kidneys or cancellous bone on red marrow dose was studied. The calculated red marrow dose varied between 0.14 and 0.42 mGy/MBq for 111In-OV-TL-3 and between 0.13 and 0.68 mGy/MBq for 131I-16.88. If the radiopharmaceutical shows high affinity for cancellous bone or another organ situated near the red marrow, the activity in these organs must be included in dose calculations. This study shows a large variation in calculated red marrow dose and selection of the definitive non-invasive approach awaits validation.
Bone Marrow↗
Intra-arterial infusion of Tc-99m MAA: a case of highly selective targeting of liver metastases and shunting.
A patient with liver metastases and on angiotensin-converting enzyme inhibition for hypertension was studied after administration of Tc-99m MAA through the hepatic artery. The scintigrams showed a highly selective perfusion of the metastases (and significant shunting) despite the systemic treatment with a vasoactive drug that, theoretically, diminishes the flow to metastases. A possible effect of concomitant vasoactive medication on targeting and systemic side effects should be considered if regional perfusion studies and intra-arterial treatment are performed.
Enalapril↗
Reduced perfusion and uptake of Tc-99m HDP in the iliac bone. A rare presentation of pelvic osteomyelitis.
The authors present a case report of a young patient with two osteomyelitic foci. Bone scintigraphy showed a rare combination of a cold and a hot spot. Possible problems in the interpretation of the scintigram in patients with pelvic osteomyelitis are discussed.
Child↗
Clinical screening of monoclonal antibodies 323/A3, cSF-25 and K928 for suitability of targetting tumours in the upper aerodigestive and respiratory tract.
Immunohistochemical characterization of three monoclonal antibodies (MAbs), designated 323/A3, SF-25 and K928, on a panel of 330 head and neck and lung tumours indicated their potential for targetting tumours in the upper aerodigestive and respiratory tract. Subsequently, MAbs were screened in a clinical phase I/II radioimmunoscintigraphic (RIS) trial for the detection of primary tumours and lymphnode metastases in patients with histologically proven squamous cell carcinoma of the head and neck (HNSCC). In 10 HNSCC patients MAbs 323/A3 F(ab')2 (n = 3), chimeric (mouse-human) SF-25 IgG (n = 1), and K928 IgG (n = 6) were evaluated for their suitability for tumour targetting. Monoclonal antibodies 323/A3 and K928 were shown to be capable of detection of HNSCC. However, there was uptake at non-tumour sites, for MAb 323/A3 in the thyroid gland, liver and skeleton, probably bone marrow, and for MAb K928 in liver, spleen and the skeleton, probably bone marrow. At a higher K928 dose, uptake in the liver was diminished but still substantial. cSF-25 was not capable of detecting HNSCC, due to the rapid and extensive uptake at non-tumour sites such as liver, spleen, brain and the skeleton, probably bone marrow. Radioactivity uptake at non-tumour sites could be mainly explained by the presence of good accessible antigenic sites and will definitely limit the application of these pan-carcinoma MAbs for therapeutic purposes.
Aged↗
Clinical imaging of head and neck cancer with technetium-99m-labeled monoclonal antibody E48 IgG or F(ab')2.
METHODS: In 32 patients who were suspected of having a neck lymph node metastasis from a histologically proven squamous-cell carcinoma of the head and neck (HNSCC), the diagnostic value of 99mTc-labeled (750 MBq) monoclonal antibody (1-2 mg) E48 IgG (n = 17) and its F(ab')2 fragment (n = 15) was evaluated and compared. Preoperative findings on lymph node status obtained by radioimmunoscintigraphy (RIS), computerized tomography (CT), magnetic resonance imaging (MRI) and palpation were defined per side (left and/or right side of the neck) as well as per lymph node level (I through V) and compared to the histopathological outcome of the neck dissection specimen. RESULTS: All 31 tumors at the primary site were visualized. RIS was correct in 201 of 221 levels (accuracy 91%) and in 38 of 47 sides (accuracy 81%). Fifteen levels and seven sides with limited tumor load were scored false-negative and five levels and two sides were scored false-positive. Sensitivity and specificity of RIS were similar to those of palpation, CT and MRI. The diagnostic value of RIS with E48 F(ab')2 or E48 IgG appeared to be similar. CONCLUSIONS: The present study shows that RIS with either E48 F(ab')2 or E48 IgG is as valuable as the other imaging techniques. The selective accumulation of radioactivity in tumor tissues, in combination with the known intrinsic radiosensitivity of HNSCC, justifies the development of radioimmunoconjugates for radioimmunotherapy.
Aged↗
Kinetics and tissue distribution of the radiolabeled chimeric monoclonal antibody MOv18 IgG and F(ab')2 fragments in ovarian carcinoma patients.
Twenty-four patients suspected of having ovarian carcinoma received i.v. injection with a combination of radiolabeled intact IgG (1 mg) and F(ab')2 fragments (1 mg) of the chimeric monoclonal antibody MOv18, each form labeled with 1.85 MBq 131I or 125I. Laparotomy was performed either 2 or 6 days after injection, and the uptake of radioactivity was determined in a total of 329 biopsies of normal and malignant tissues. The mean elimination half life in plasma of cMOv18 IgG and F(ab')2 was 70 +/- 8 (SD) and 20 +/- 5 h, respectively. The mean uptake of IgG in tumor biopsies was 3.6-fold higher two days after injection and 6.9-fold higher than the uptake of F(ab')2 6 days after injection. Uptake in normal tissues was 3.3 and 5.5 times higher for IgG at 2 and 6 days, respectively. Two days after injection, the mean ratio of the uptake in tumor:normal tissue/patient was 3.8 +/- 1.5 and 4.0 +/- 1.8 for radiolabeled cMOv18 IgG and F(ab')2, respectively. Six days after injection, this was 6.7 +/- 4.7 for Ig G and 5.7 +/- 4.1 for F(ab')2. cMOv18 IgG has a longer circulation time in blood, a higher uptake in tumor and normal tissues, and a longer retention time compared to the F(ab')2 fragments. However, the tumor:normal tissue ratios are similar. The results do not warrant a definite conclusion as to which antibody form is most suitable for therapeutic application of antibodies but provide a more firm basis for rational design of therapeutic targeting studies using immunoconjugates.
Adult↗
Radioimmunoscintigraphy of head and neck cancer using 99mTc-labeled monoclonal antibody E48 F(ab')2.
The diagnostic value of 99mTc-labeled monoclonal antibody E48 F(ab')2 (750 MBq, 1 mg) was evaluated in 10 patients with a histologically proven squamous cell carcinoma of the head and neck and with clinical evidence of cervical lymph node involvement. Preoperative findings on lymph node status obtained by radioimmunoscintigraphy (RIS), computerized tomography, magnetic resonance imaging, and palpation were defined per side (left and/or right side of the neck) as well as per lymph node level (I through V) and compared with the histopathological outcome of the neck dissection specimen. In 10 patients, all 8 known tumors at the primary site were detected by RIS. Furthermore, RIS was correct in 13 of 13 tumor involved neck sides and in 17 of 20 tumor involved lymph node levels. False-negative observations comprised 3 levels containing tumor deposits smaller than 1 cm in diameter, 2 of which were not detected by any other diagnostic modality. Palpation, computerized tomography, and magnetic resonance imaging were correct in, respectively, 13, 15, and 15 of the 20 tumor involved levels. There were 2 false-positive observations with monoclonal antibody E48 and 3 with palpation. No false-positive detections occurred with computerized tomography or magnetic resonance imaging. In two of the patients, RIS provided clinically important information which was not provided by any other diagnostic method. In one patient, recurrence of laryngeal carcinoma was established at the primary site after previous radiotherapy. In another patient, bilateral instead of unilateral lymph node involvement became apparent. These preliminary data indicate that radioimmunoscintigraphy with monoclonal antibody E48 may be helpful in the diagnosis of metastatic and recurrent head and neck cancer.
Adolescent↗