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D A Piers

Publications and source records attributed to D A Piers.

At least 19 recordsLinked to original sources
PubMed2002

Prevalence of reduced bone mineral density in patients with anti-neutrophil cytoplasmic antibody associated vasculitis and the role of immunosuppressive therapy: a cross-sectional study.

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis is a relapsing-remitting disease, which is treated with corticosteroids (CS) in combination with cyclophosphamide. One of the major side-effects of this treatment is osteoporosis, which may result in the increased occurrence of fractures. In the present study we measured the prevalence of reduced bone mineral density (BMD) in a cross-sectional cohort of patients and correlated BMD findings with cumulative doses of CS and/or cyclophosphamide. BMD was measured by dual-energy X-ray absorptiometry (DXA) of the lumbar spine, radius and proximal femur between January 1998 and December 1999. Cumulative doses of CS and cyclophosphamide were calculated by chart review. Ninety-nine consecutive patients (48 men, 51 women) aged 55 +/- 16 years (mean +/- SD) were studied 50 months (median; range 0-400 months) after a diagnosis of ANCA-associated vasculitis had been made. Sixty-nine patients were treated with 10.7 g (median cumulative dose; range 0.4-67.2 g) of CS, and 88 patients were treated with 34.1 g (median cumulative dose; range 0.8-324.3 g) of cyclophosphamide. Fifty-seven percent of the patients had osteopenia (T-score: -1 to -2.5 SD), and 21% had osteoporosis (T-score: <-2.5 SD) at least at one site. Thirty-four of 37 (92%) postmenopausal women, 9 of 14 (64%) premenopausal women, and 34 of 48 (71%) men had either osteopenia or osteoporosis. The mean age- and sex-adjusted BMD (Z-score) of the proximal femur in men was found to be significantly lower than zero. Cumulative dose of CS therapy showed an inverse relation with Z-scores at the lumbar spine (p = 0.035) and proximal femur (p = 0.011). Cumulative dose of cyclophosphamide was not correlated with Z-scores. Osteopenia and osteoporosis are thus frequently observed in patients with ANCA-associated vasculities. However, only in men is the mean Z-score significantly lower than zero. Cumulative dose of CS therapy is significantly associated with bone loss at the spine and femur.

Adult↗
PubMed2001

Continuous leakage measurement during hyperthermic isolated limb perfusion.

BACKGROUND: Continuous measurement of perfusate leakage into the systemic circulation is of the utmost importance and can be performed with the help of radioactive tracers. The purpose of this study was to assess changes in the perfusion leakage rate between two periods: 1977-1990 and 1991-2000, and to determine the factors responsible for these changes. METHODS: During the 1991-2000 period, 119 patients underwent HILP mainly for locally recurrent melanoma or locally advanced soft tissue sarcoma. HILP was performed with melphalan (33%) or in combination with TNFalpha (65%). There were 67 iliacal, 12 femoral, 25 popliteal, and 15 axillary perfusions performed. Leakage into the systemic circulation was monitored continuously with the help of 131I-albumin and a stationary scintillation detector placed above the heart. RESULTS: The median maximum leakage was 2.7% (range 0%-21%) which is significantly less than the previous period (1977-1990) where leakage of 8% (range 0%-30%) was reported (P < .05). A statistical difference in leakage was detected among perfusion locations where the iliac and femoral vessels showed more leakage than the axillary and popliteal vessels (P < .05). Furthermore, there appeared to be significantly less leakage when TNFalpha was used than when melphalan was the sole drug (P < .05). CONCLUSIONS: Nowadays leakage from isolated perfusions into the systemic circulation is further minimized compared with the days when melphalan was the sole drug used. Increased awareness about TNFalpha leakage, continuous external monitoring with 131I-albumin as the main isotope, flow rate regulation in the perfusion circuit, and regulation of the patient's systemic blood pressure have all been major contributors to this improvement.

Adolescent↗
PubMed2001

No difference in cardiac event-free survival between positron emission tomography-guided and single-photon emission computed tomography-guided patient management: a prospective, randomized comparison of patients with suspicion of jeopardized myocardium.

OBJECTIVES: We sought to prospectively compare nitrogen-13 (13N)-ammonia/18fluorodeoxyglucose (18FDG) positron emission tomography (PET)-guided management with stress/rest technetium-99m (99mTc)-sestamibi single-photon emission computed tomography (SPECT)-guided management. BACKGROUND: Patients with evidence of jeopardized (i.e., ischemic or viable) myocardium may benefit from revascularization, whereas patients without it should be treated with drugs. Both PET and SPECT imaging have been proven to delineate jeopardized myocardium. When patient management is based on identification of jeopardized myocardium, it is unknown which technique is most accurate for long-term prognosis. METHODS: In a clinical setting, 103 patients considered for revascularization with left ventricular wall motion abnormalities and suspicion of jeopardized myocardium underwent both PET and SPECT imaging. The imaging results were used in a randomized fashion to determine management (percutaneous transluminal coronary angioplasty [PTCA], coronary artery bypass graft surgery [CABG] or drug treatment). Follow-up for cardiac events (cardiac death, myocardial infarction and revascularization) was recorded for 28 +/- 1 months. The study was designed to have a power of 80% to detect a 20% difference in the event rate between PET- and SPECT-based management. RESULTS: Management decisions in 49 patients randomized to PET (12 who had PTCA, 14 CABG and 23 drug therapy) were comparable with 54 patients randomized to SPECT (15 who had PTCA, 13 CABG and 26 drug therapy). In terms of cardiac event-free survival, no differences between PET and SPECT were observed (11 vs. 13 cardiac events for PET and SPECT, respectively; p = NS by the Kaplan-Meier statistic). CONCLUSIONS: No difference in patient management or cardiac event-free survival was demonstrated between management based on 13N-ammonia/18FDG PET and that based on stress/rest 99mTc-sestamibi SPECT imaging. Both techniques may be used for management of patients considered for revascularization with suspicion of jeopardized myocardium.

Aged↗
PubMed2001

Routine bone scans in patients with prostate cancer related to serum prostate-specific antigen and alkaline phosphatase.

OBJECTIVE: To evaluate the need for a bone scan as a routine staging procedure in patients with newly diagnosed prostate cancer in relation to serum prostate-specific antigen (PSA) and alkaline phosphatase (ALP) levels, and thus determine whether a reduction of the use of this staging method is possible in patients with a low probability of osseous metastasis. PATIENTS AND METHODS: The results of bone scans were related retrospectively to levels of serum PSA and ALP in 363 patients with prostate cancer newly diagnosed between 1989 and 1997. RESULTS: Of 363 consecutive patients, 111 had a positive bone scan. In 19 of 144 (13%, "missed diagnosis") patients with a PSA level of < 20 ng/mL the bone scan was positive. In 125 patients (49%, "false-positives") with a PSA level of > 20 ng/mL the bone scan was negative. A threshold level of 100 U/L for ALP gave a better balance for the number of "false-positives" and "missed diagnosis". ALP values correlated better with an abnormal bone scan than did PSA levels; ALP levels of > 90 U/L indicated a 60% chance for the presence of bone metastases. CONCLUSION: Patients with newly diagnosed and untreated prostate cancer should undergo bone scintigraphy if there is bone pain or if ALP levels are > 90 U/L. Recent reports discourage the routine use of a bone scan when the serum PSA level is <20 ng/mL. However, the present series suggests there is a greater chance of a positive bone scan in patients with low PSA levels; these findings need further confirmation.

Aged↗
PubMed2001

Uptake mechanisms of L-3-[125I]iodo-alpha-methyl-tyrosine in a human small-cell lung cancer cell line: comparison with L-1.

The radiolabelled amino acid analogue L-3-[125I]iodo-alpha-methyl-tyrosine (IMT) is under evaluation in brain tumours, where it reflects amino acid transport activity, but is also taken up in many other tumour types. This study investigated the uptake mechanism of IMT in tumour cells not derived from brain tumours, in comparison with the native amino acid 14C-tyrosine (Tyr) from which IMT is derived. Human GLC4 small-cell lung cancer cells in log-phase were incubated with IMT and Tyr. Tracer uptake was determined in various buffers, incubation periods, concentrations of specific amino acid transport blockers, pH and temperature. IMT uptake was very fast, reaching a plateau within 5 min, while Tyr kept on accumulating for > 60 min. Based on steady-state experiments, > 90% of IMT uptake could be attributed to amino acid transport activity. The L transport system was the most important, both for IMT and Tyr. IMT uptake into GLC4 tumour cells is almost completely the result of amino acid transport activity (especially the L system) and is very similar to Tyr uptake. Therefore, also outside the brain, IMT is a metabolic tracer that may reflect the increased amino acid transport that is characteristic for malignant tumours.

Amino Acids↗
PubMed2001

Radiolabeled amino acids: basic aspects and clinical applications in oncology.

As the applications of metabolic imaging are expanding, radiolabeled amino acids may gain increased clinical interest. This review first describes the basic aspects of amino acid metabolism, then continues with basic aspects of radiolabeled amino acids, and finally describes clinical applications, with an emphasis on diagnostic value. A special focus is on (11)C-methionine, (11)C-tyrosine, and (123)I-iodomethyltyrosine, because these have been most used clinically, although their common affinity for the L-transport systems may limit generalization to other classes of amino acids. The theoretic and preclinical background of amino acid imaging is sound and supports clinical applications. The fact that amino acid imaging is less influenced by inflammation may be advantageous in comparison with (18)F-FDG PET imaging, although tumor specificity is not absolute. In brain tumor imaging, the use of radiolabeled amino acids is established, the diagnostic accuracy of amino acid imaging seems adequate, and the diagnostic value seems advantageous. The general feasibility of amino acid imaging in other tumor types has sufficiently been shown, but more research is required in larger patient series and in well-defined clinical settings.

Amino Acids↗
PubMed2001

L-3-[123I]iodo-alpha-methyl-tyrosine SPECT in non-small cell lung cancer: preliminary observations.

UNLABELLED: L-3-[123I]iodo-alpha-methyl-tyrosine (IMT) is a modified amino acid that is avidly taken up by many tumors. Uptake is based on the increased transmembrane transport of amino acids in malignancies. IMT is the only amino acid tracer suitable for SPECT. The aim of this study was to determine the feasibility of IMT SPECT in the detection, staging, and treatment evaluation of non-small cell lung cancer. METHODS: We evaluated 44 IMT SPECT studies in 17 patients with histologically proven non-small cell lung cancer, stage III. IMT SPECT and planar imaging of the chest was performed before, 2 wk after, and 3 mo after 60 Gy radiotherapy. Staging was based on the findings of bronchoscopy, chest CT, mediastinoscopy, or explorative thoracotomy. After radiotherapy, CT and bronchoscopy were repeated to assess tumor response. RESULTS: In 15 of 16 evaluable primary tumors, avid IMT uptake was present (sensitivity, 94%), with a mean (+/-SD) tumor-to-background ratio (T/B) of 2.95 +/- 0.78 (range, 1.7-4.9). In 12 of 14 patients (86%) with mediastinal involvement, IMT SPECT detected one or more mediastinal metastases. However, only 13 of 20 mediastinal metastases were detected in lesion analysis (lesion-based sensitivity, 65%). For lesions < 2 cm in diameter, sensitivity was 42%. FDG PET (available for 5 patients) detected more known and unknown lesions than did IMT SPECT. After radiotherapy, T/B had fallen to 1.84 +/- 0.29 (P < 0.001 vs. baseline), and 3 mo later to 1.61 +/- 0.41 (not statistically significant vs. second study). Considerable nonspecific uptake was found in irradiated normal lung tissue (mean ratio to nonirradiated tissue, 1.79 +/- 0.53), persisting for > 3 mo. No relationship was observed between various IMT uptake parameters and the presence of residual viable tumor tissue or survival. CONCLUSION: IMT SPECT has a high sensitivity for the detection of primary non-small cell lung cancer. Although patient-based sensitivity in detecting mediastinal spread was adequate, sensitivity for individual lesions, especially for small metastases (<2 cm in diameter) was too low to be clinically helpful. Radiotherapy caused considerable nonspecific IMT uptake, which also limits applicability in evaluating the results of treatment.

Adult↗
PubMed2000

Efficacy of coughing in tetraplegic patients.

STUDY DESIGN: A randomized cross-over design study in six tetraplegic patients. OBJECTIVES: To investigate the efficacy of coughing in tetraplegic patients. SUMMARY OF BACKGROUND DATA: In tetraplegic patients, pulmonary complications due to insufficient clearance of bronchial mucus frequently are described. Coughing in tetraplegic patients is thought to be insufficient because of severely impaired expiratory muscle function. More recently, however, it has been reported that many tetraplegic patients may have dynamic airway compression and thus a more or less effective cough. METHODS: Mucus clearance was measured using a radioactive aerosol tracer technique during 45 minutes on 2 days: once without intervention, and once with voluntary coughing in the period 15 to 30 minutes (once every 30 seconds). Measurements were done in a randomized order. For each day, individual slopes for the decrease in radioactivity were calculated, reflecting mucus transport in the peripheral, central, and the whole lung region. RESULTS: Significant differences in slopes were found between the control day and the cough day in the peripheral lung region for the interval 0 to 30 minutes and in the whole lung region for the interval 0 to 30 minutes and 0 to 45 minutes. The improvement of mucus clearance due to coughing, however, was relatively small in these patients, only 3% after 45 minutes: from 4% whole lung clearance during quiet breathing to 7% whole lung clearance during coughing. CONCLUSION: Tetraplegic patients may achieve a statistically significant increase in their bronchial mucus transport by voluntary coughing.

Adult↗
PubMed2000

Lymphatic mapping with intralesional tracer administration in breast carcinoma patients.

BACKGROUND: The objectives of the study were to determine how often a sentinel lymph node is visualized by lymphoscintigraphy in breast carcinoma patients, how often the sentinel lymph node is identified during surgery, and the sensitivity of these procedures to identify the presence of axillary lymph node metastasis. METHODS: A total of 136 patients were enrolled in 2 hospitals. Preoperative dynamic and static lymphoscintigraphy were performed; in addition, both a vital dye and a gamma detection probe were used intraoperatively. The tracers were injected into the primary lesion. Sentinel lymph node biopsy was followed by completion axillary lymph node dissection. The sentinel lymph nodes and other axillary lymph nodes were examined routinely and by immunohistochemical staining. RESULTS: A sentinel lymph node was visualized by lymphoscintigraphy in 118 patients (87%). During the operation a sentinel lymph node was localized in 126 patients (93%). A total of 224 sentinel lymph nodes were harvested (average of 1.7 and range of 1-4 sentinel lymph nodes per patient). Of all the sentinel lymph nodes, 37 were blue (17%), 68 were radioactive (30%), and 119 were both blue and radioactive (53%). The sentinel lymph nodes contained metastatic disease in 56 patients (44%). Three sentinel lymph node biopsies were false-negative (sensitivity 95%). CONCLUSIONS: Sentinel lymph node biopsy with preoperative lymphoscintigraphy after intralesional tracer administration and intraoperative use of both a gamma detection probe and a vital dye is a reliable technique for staging the axilla of breast carcinoma patients.

Adult↗
PubMed2000

Sentinel node biopsy for melanoma in the head and neck region.

BACKGROUND: Lymphatic drainage in the head and neck region is known to be particularly complex. This study explores the value of sentinel node biopsy for melanoma in the head and neck region. METHODS: Thirty consecutive patients with clinically localized cutaneous melanoma in the head and neck region were included. Sentinel node biopsy was performed with blue dye and a gamma probe after preoperative lymphoscintigraphy. Average follow-up was 23 months (range, 1-48). RESULTS: In 27 of 30 patients, a sentinel node was identified (90%). Only 53% of sentinel nodes were both blue and radioactive. A sentinel node was tumor-positive in 8 patients. The sentinel node was false-negative in two cases. Sensitivity of the procedure was 80% (8 of 10). CONCLUSIONS: Sentinel node biopsy in the head and neck region is a technically demanding procedure. Although it may help determine whether a neck dissection is necessary in certain patients, further investigation is required before this technique can be recommended for the standard management of cutaneous head and neck melanoma.

Adult↗
PubMed2000

Bone mineral density in the long term after liver transplantation.

Hepatic osteodystrophy is a complication of chronic liver disease and bone mass is known to decline further in the first year after liver transplantation. The present study focused on bone mineral density (BMD) between 1 and 15 years after liver transplantation under a prednisolone- and azathioprine-based immunosuppressive regimen. Three groups of adult patients were studied: group 1, 45 patients with a follow-up of 5-9 years after transplantation, had BMD measurements done at 1, 2 and 5 years after transplantation; group 2, 17 patients with a follow-up of 10-14 years, had BMD measurements done at 5 and 10 years; group 3, 4 patients with a follow-up of more than 15 years, had BMD measurements done at 10 and 15 years. BMD of lumbar spine (L1-L4) and proximal femur was measured using dual-energy X-ray absorptiometry, and at the same time radiographs of the spine and hips were made. Spinal BMD increased significantly, during the second post-transplant year; subsequently no significant changes were seen. Proximal femur BMD decreased slightly, but significantly during the second year, and remained stable afterwards. About one-third of patients had a BMD below the fracture threshold (= 0.798 g/cm2 for the lumbar spine and 0.675 g/cm2 for the hip) during the follow-up. In 5 of the 66 patients studied, new vertebral fractures occurred. No fractures or avascular necrosis of the hips were seen. Furthermore, after transplantation lower Z-scores of the hip were found in patients with pre-transplant cholestatic liver diseases, and lower Z-scores of the lumbar spine were found in men compared with women. Long-term follow-up of BMD up to 15 years after transplantation revealed an improvement mainly in the second postoperative year with no deterioration afterwards. Nevertheless a substantial number of patients (around one-third) kept a BMD below the fracture threshold, and new fractures may occasionally occur. The overall outcome appeared somewhat less favorable in men and patients transplanted for cholestatic liver diseases.

Absorptiometry, Photon↗
PubMed2000

Limited role of meta-iodobenzylguanidine scintigraphy in imaging phaeochromocytoma in patients with multiple endocrine neoplasia type II.

OBJECTIVE: To compare diagnostic applicability of combined computed tomography (CT) and magnetic resonance imaging (MRI), with that of meta-iodobenzylguanidine (MIBG) scintigraphy in the preoperative localisation of MEN II related phaeochromocytoma. DESIGN: Retrospective study SETTING: University hospital, The Netherlands. MATERIALS: 17 patients with MEN II patients (33 adrenal glands) who were operated on for phaeochromocytoma. MIBG scintigraphy, CT and MRI were used to localize phaeochromocytoma. Histopathologically, an adrenomedullary lesion more than 1 cm in size was classified as a phaeochromocytoma. MAIN OUTCOME MEASURES: Sensitivity, specificity, and diagnostic accuracy of combined CT and MRI and MIBG scintigraphy, compared with histopathological findings. RESULTS: Sensitivity of combined CT and MRI (27 adrenal glands) was 87%, with a specificity of 100% and a diagnostic accuracy of 89%. MIBG scintigraphy (31 adrenal glands) had a sensitivity of 92%, a specificity of only 17%, and a diagnostic accuracy of 77%. CONCLUSION: If unilateral adrenalectomy is done when only one adrenal gland contains a phaeochromocytoma, then MRI should be the method of choice for localising MEN type II related phaeochromocytoma. MIBG scintigraphy can be restricted to those patients in whom MRI does not show a tumour.

3-Iodobenzylguanidine↗
PubMed2000

Sentinel lymph node procedure is highly accurate in squamous cell carcinoma of the vulva.

PURPOSE: To determine the diagnostic accuracy of the sentinel lymph node procedure in patients with squamous cell carcinoma of the vulva and to investigate whether step sectioning and immunohistochemistry of sentinel lymph nodes increase the sensitivity for detection of metastases. PATIENTS AND METHODS: Between July 1996 and July 1999, 59 patients with primary vulvar cancer were entered onto a two-center prospective study. All patients underwent sentinel lymph node procedure with the combined technique (preoperative lymphoscintigraphy with technetium-99m-labeled nanocolloid and intraoperative blue dye). Radical excision of the primary tumor with uni- or bilateral inguinofemoral lymphadenectomy was performed subsequently. Sentinel lymph nodes and lymphadenectomy specimens were sent for histopathologic examination separately. Sentinel lymph nodes, negative at the time of routine pathologic examination, were re-examined with step sectioning and immunohistochemistry. RESULTS: In 59 patients, 107 inguinofemoral lymphadenectomies were performed (11 unilateral and 48 bilateral). All sentinel lymph nodes, as observed on preoperative lymphoscintigram, were identified successfully intraoperatively. Routine histopathologic examination showed lymph node metastases in 27 groins, all of which were detected by the sentinel lymph node procedure. The negative predictive value for a negative sentinel lymph node was 100% (97.5% confidence interval [CI], 95% to 100%). Step sectioning and immunohistochemistry showed four additional metastases in 102 sentinel lymph nodes (4%; 95% CI, 1% to 9%) that were negative at the time of routine histopathologic examination. CONCLUSION: Sentinel lymph node procedure with the combined technique is highly accurate in predicting the inguinofemoral lymph node status in patients with early-stage vulvar cancer. Future trials should focus on the safe clinical implementation of the sentinel lymph node procedure in these patients. Step sectioning and immunohistochemistry slightly increase the sensitivity of detecting metastases in sentinel lymph nodes and should be included in these trials.

Adult↗
PubMed2000

Imaging of soft-tissue tumors using L-3-[iodine-123]iodo-alpha-methyl-tyrosine single photon emission computed tomography: comparison with proliferative and mitotic activity, cellularity, and vascularity.

The radiolabeled amino acid L-3-[123I]-iodo-alpha-methyltyrosine (IMT) is a new tumor tracer that accumulates in many tumors and is suitable for single photon emission computed tomography (SPECT) imaging. Using IMT SPECT, we studied 32 patients with a soft-tissue tumor suspected to be a soft-tissue sarcoma to determine whether: (a) tumors can be visualized; (b) benign and malignant lesions can be distinguished; and (c) IMT uptake is related to tumor grade and proliferation. Whole-body imaging was performed 15 min after administration of 300 MBq IMT, biopsy, or resection 1-2 weeks later. IMT uptake was quantified using a region-of-interest method resulting in tumor:background (T:B) ratios. These were compared with tumor grade, mitotic index, tumor cellularity, vascularity, and the Ki-67 proliferation index. Eleven patients had a benign tumor, and 21 patients had a soft-tissue sarcoma. Six benign tumors demonstrated minor IMT uptake, and five lipomas had no uptake. All malignant tumors had high uptake and were clearly visualized. T:B ratios in malignant tumors (3.83 +/- 1.16) were higher (P < 0.001) than in benign tumors (1.52 +/- 0.60). Small (<5 mm) metastases in two patients were not detected. Taking the T:B ratio 2.0 as the cutoff level, the sensitivity for detection of malignancy was 100%, and specificity was 88%. IMT uptake correlated with histological grade (r = 0.82; P < 0.001), mitotic index (r = 0.75; P < 0.001), tumor cellularity (r = 0.73; P < 0.01), and with the Ki-67 proliferation index (r = 0.63; P < 0.01). In conclusion, IMT SPECT visualized all soft-tissue sarcomas. Uptake in sarcomas was clearly higher than in benign lesions, yielding 100% sensitivity for detection of malignancy at 88% specificity. Uptake increased with higher tumor grade and higher proliferation rate.

Adolescent↗