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Biomedical subjects

R Howman-Giles

Publications and source records attributed to R Howman-Giles.

At least 55 records · Page 3Linked to original sources
PubMed1995

Sentinel lymph node status as an indicator of the presence of metastatic melanoma in regional lymph nodes.

The value of elective lymph node dissection (ELND) for melanoma patients with clinically uninvolved regional nodes remains controversial. However, it has been proposed that selective 'sentinel' lymph node biopsy reliably identifies individuals with micrometastases, who are most likely to benefit from full ELND. The aim of this study was to confirm that metastatic melanoma cells travelling in lymphatics do not bypass the sentinel node. After preoperative lymphoscintigraphy and intraoperative injection of blue dye around the primary melanoma site, sentinel node biopsy was performed in 118 melanoma patients for whom full ELND was planned as part of their definitive surgical treatment. A confidently identified sentinel node was tumour positive in 22 out of 105 regional lymph node fields (21%). In 18 cases the sentinel node was the only node found to be involved and in four cases, additional nodes were positive. In two other patients a positive node was found when the sentinel lymph node had been negative. However, in each case an avoidable error of technique had occurred and definite blue staining indicated that the positive node was in fact another sentinel node. This study thus confirms that sentinel lymph node status reliably indicates whether metastatic melanoma is present in regional lymph nodes.

Adolescent↗
PubMed1995

Volumetric bone mineral density--a potential role in paediatrics.

The use of areal bone mineral density (aBMD) in paediatric populations has aroused some concern, as it fails to take the age-related increase in bone thickness into account. We have developed a measure of true bone density, volumetric bone mineral density (vBMD), which is independent of age and height. In order to examine the relationship between growth parameters, aBMD and vBMD, we studied patients with phenylketonuria (PKU, n = 40), chronic renal failure (CRF, n = 27) and chronic asthma (n = 19). aBMD of the femoral neck and the mid-femoral shaft was measured using dual energy X-ray absorptiometry (DXA), vBMD was calculated on the basis of values of bone mineral content and bone dimension provided by DXA, with the assumption that both sites are cylinders. aBMD and vBMD were then compared with the normal reference, expressed as a standard deviation score (SDS). aBMD and vBMD were normal in the femoral neck region of the PKU group, but aBMD, either standardized for age or for height, was low in the femoral shaft region (p < 0.01). In the CRF group, profound growth retardation was seen (mean height SDS, -3.2) and aBMD and vBMD were both low in the femoral shaft region but not in the femoral neck. In the asthma group, aBMD for age was low at both sites, but vBMD did not differ from that seen in normal individuals. We conclude that the true vBMD provides a different interpretation of bone density compared with aBMD and requires further evaluation in paediatrics because of its age and height independence.

Absorptiometry, Photon↗
PubMed1995

Hepatobiliary disease in cystic fibrosis patients with pancreatic sufficiency.

Focal and multilobular biliary cirrhosis are considered pathognomonic of cystic fibrosis (CF) and almost invariably have been reported in patients with steatorrhea. In contrast, patients with pancreatic sufficiency and normal absorption are considered less likely to develop liver or biliary tract problems. The authors report three patients with CF and pancreatic sufficiency, presenting with recurrent abdominal pain (unrelated to pancreatitis). All had common bile duct disease, one with multilobular cirrhosis and portal hypertension. Pancreatic sufficiency was proven by quantitative pancreatic stimulation tests, 3-day fecal fat analyses, and serum pancreatic isoamylases. All three patients had mild lung disease. Two were homozygous for the common delta F508 mutation, and the other, a delta F508 compound heterozygote. Hepatobiliary structure and function were determined by serial hepatobiliary scintigraphy, percutaneous transhepatic cholecystography, and biochemical liver function tests. Patients 1 and 3 had mild hepatomegaly, normal liver biochemistry, and distal common bile duct strictures. Patient 2 had a firm nodular liver with splenomegaly, abnormal liver biochemistry, and a cholangiographic appearance of sclerosing cholangitis. All have undergone operative treatment for persistent abdominal pain. These cases confirm the occurrence of common bile duct pathology and liver disease in patients with CF and pancreatic sufficiency. They demonstrate that liver and biliary tract disease can occur independently of the underlying disease severity and the presence of steatorrhea. Further, they suggest that obstruction of the biliary tract may be an additional factor in the evolution of liver disease in CF.

Biliary Tract Diseases↗
PubMed1995

Thallium-201 scintigraphy in pediatric soft-tissue tumors.

UNLABELLED: Thallium-201 has been used as a tumor imaging agent in adults with lymphoma, brain tumors, thyroid carcinoma and bone sarcomas. The application of 201Tl in pediatric oncology has been very limited. METHODS: Whole-body 201Tl studies were incorporated into the imaging protocols of 45 children with solid soft-tissue tumors. Bone and 67Ga scans as well as 131I-MIBG scans for patients with neuroblastoma were obtained. RESULTS: Seventeen children with lymphoma, five with Hodgkin's disease and twelve with non-Hodgkin's lymphoma (NHL) were studied. All of the patients with Hodgkin's disease showed avid uptake of 201Tl and 67Ga. The six patients with B-cell NHL had positive 67Ga scans and four had positive 201Tl scans. There was variable uptake in T-cell and undifferentiated lymphoma with an overall sensitivity of 69% for 201Tl and 85% for 67Ga. In 14 patients with rhabdomyosarcoma, 10 (71%) had positive 201Tl scans and 11 (79%) had positive 67Ga images. Gallium and thallium scans detected lesions equally. There was poor uptake of 201Tl in the six children with neuroblastoma. Primary tumor and metastases were detected more readily with the bone and MIBG scans. Three children with Wilms' tumor had poor or no uptake on 201Tl images, two of three patients with histocytosis had no significant uptake and one patient had mild uptake of 201Tl. One patient with primitive neuroectodermal tumor had positive 201Tl and 67Ga images and one patient with a neurofibrosarcoma had negative 201Tl and 67Ga images. There was no correlation with histological types of tumor or disease staging. CONCLUSION: This study shows significant uptake of 201Tl in many pediatric solid soft-tissue tumors. Additional study is needed to determine 201Tl effects on treatment response and tumor viability. Also, more studies are needed to assess 201Tl delayed images to determine if there is more tracer concentration in the tumors.

3-Iodobenzylguanidine↗
PubMed1995

Gallium and thallium scintigraphy in pediatric peripheral primitive neuroectodermal tumor (Askin tumor) of the chest wall.

A 3.5-yr-old child presented with a large thoracic mass which showed avid accumulation of 67Ga and 201Tl was studied. Histology showed a peripheral neuroectodermal tumor of the chest wall typical of the malignancy described as the Askin tumor. The 201Tl studies were a more accurate method of following tumor response to therapy than 67Ga scintigraphy.

Child, Preschool↗
PubMed1994

Bone mineral density of total body, spine, and femoral neck in children and young adults: a cross-sectional and longitudinal study.

Bone mineral density (BMD) of total body (TBMD), lumbar spine (L2-4), and femoral neck was measured in 266 normal subjects (136 males) aged 4-27 years (mean 13 years) using dual-energy x-ray absorptiometry (DXA). BMD of all sites increased significantly with age until 17.5 years in males and 15.8 years in females, except for femoral neck BMD in females, which peaked at age 14.1 years. Males had higher peak TBMD, which was attributed to greater weight and lean tissue mass. In contrast, despite a later timing, peak L2-4 BMD in males was not different from that in females. Before peak BMD, weight was the best predictor of TBMD and L2-4 BMD in both sexes (r2 ranged from 0.77 to 0.88), whereas femoral neck BMD was predicted equally by height and weight. Longitudinal information collected from 53 (25 boys) of these children, aged 4-16.9 years, showed that the average annualized gain in TBMD was 0.047 g/cm2 for boys and 0.039 g/cm2 for girls. No significant difference in the association between age and BMD (slopes) was found between cross-sectional and longitudinal data for either sex. We conclude that the timing for peak BMD was consistent for total body, lumbar spine, and femoral neck for each sex. The earlier peak BMD in females is most likely related to earlier puberty. The cross-sectional normative data of this study are useful in serving as a standard for serial assessment in health and disease states.

Absorptiometry, Photon↗
PubMed1994

Bone and gallium scintigraphy in children with rhabdomyosarcoma: a 10-year review.

Technetium-99m bone and Gallium-67 scintigraphy has been widely used in the management of children with solid tumors. A retrospective review of all patients with rhabdomyosarcoma (RMS) from January 1980 to December 1989 was undertaken in order to determine the sensitivity and specificity of scintigraphy in detection of metastatic disease and to determine optimum frequency of serial scans in follow up. Over the 10-year period, 40 patients were diagnosed and treated for RMS: 22 were newly diagnosed from 1980-1984 and of these 16 had a minimum 5-year disease-free period whilst 6 died of the disease, giving a cure rate of 73%. A total of 271 bone and 236 Gallium-67 scans were performed. With respect to detection of metastatic disease in all tissues, Gallium-67 scans had a sensitivity of 84%, specificity 95% and bone scans had a sensitivity of 70% and specificity 95%. Bone scan sensitivity and specificity for skeletal metastases were 100% and 95%, respectively. Considering only patients with Gallium avid primary tumors, the Gallium-67 scan sensitivity was 94%. Ten patients developed new metastatic disease or primary recurrence after starting therapy, 8/10 within 12 months of diagnosis. Frequent surveillance scanning in the treatment phase, 2 years post-diagnosis, is of value in the early detection of metastases and monitoring disease response to therapy. Surveillance scanning after completion of treatment is more difficult to justify.

Adolescent↗
PubMed1994

Lymphoscintigraphy to identify sentinel lymph nodes in patients with melanoma.

Lymphoscintigraphy (LS) has been performed for 8 years in patients of the Sydney Melanoma Unit, to define lymphatic drainage patterns. Over the past 2 years, LS has also been used to locate the sentinel lymph node prior to surgery. Our technique for LS and subsequent sentinel node biopsy has an accuracy of 97%. All sentinel nodes must be marked to ensure the successful application of the sentinel biopsy technique. We have found that the axilla and groin average just over one sentinel node per draining node group for lesions on the trunk and upper limb, but have noted that drainage to the groin differed when lower limb lesions were studied. Because of the anastomosis of lymph vessels in the upper thigh, multiple sentinel nodes are identified in the groin in some patients. We have found an average of three sentinel nodes in the groin when lymph drainage from lower limb lesions was studied with LS. This difference demands a modification of the LS technique, with early imaging of the groin nodes to identify all sentinel nodes in each patient. The depth of the sentinel nodes can also be measured and the location of all interval nodes marked on the skin. This ensures that all sentinel nodes and interval nodes can be removed at the time of surgery.

Arm↗
PubMed1993

Ga-67 scintigraphy in pulmonary blastoma in a child.

Pulmonary blastoma is a rare primary malignancy of the lung with a small number of cases reported in children. The primary treatment is surgery, however radiotherapy and chemotherapy are also used. The ability to determine whether the tumor has been fully removed and when recurrence occurs is important for appropriate treatment and prognosis. A case of a 7-year-old girl with pulmonary blastoma is reported in which the primary tumor is extremely Ga-67-avid and in which the gallium scans were helpful in determining early recurrence and metastatic disease to the brain.

Brain Neoplasms↗
PubMed1993

Ga-67 scintigraphy in a child with adrenocortical carcinoma.

Adrenocortical carcinoma is a rare malignancy in childhood and often presents with a large abdominal mass and precocious puberty. The tumor is often advanced at the time of diagnosis. Radiological techniques are the main imaging modalities for assessment of the primary tumor. Ga-67 scintigraphy has been used in other pediatric solid tumors, however, no data were available for this tumor in childhood. A case of a 2.5-year-old male with a Ga-67 avid adrenocortical carcinoma is reported in which Ga-67 scintigraphy was very useful in detecting recurrence of the tumor and in assessing response to therapy.

Adrenal Cortex Neoplasms↗
PubMed1993

Gallium-67 and technetium-99m-methylene diphosphonate skeletal scintigraphy in determining prognosis for children with stage IV neuroblastoma.

Thirty-five children (aged 0-9 yr) who had presented with Stage IV neuroblastoma were studied to see if avidity for 67Ga or 99mTc-methylene diphosphonate (MDP) uptake in both primary and secondary sites at diagnosis conferred any prognostic significance. Twenty-three percent of the patients were disease free and off treatment at the time of study. Crude survival did not differ between groups. Duration of survival and the likelihood of completing treatment were related to the scintigraphic appearance at the time of diagnosis, after adjustment for potential confounding effects, using Cox's proportional hazards regression and multiple logistic regression. After adjustment for confounding influences, neither 67Ga avidity nor uptake of 99mTc-MDP was associated with a significantly worse prognosis, both in terms of adjusted survival and likelihood of completing treatment. Patients with 67Ga-avid scans at diagnosis did not demonstrate significantly worse survival (HR 1.47, 95% CI 0.43-5.11) than those without 67Ga avidity. They were somewhat less likely to complete treatment (OR 0.23, 95% CI 0.03-1.63), but this did not reach statistical significance. Similarly, although patients with 99mTc-MDP positive scans demonstrated somewhat worse survival (HR 2.47, 95% CI 0.45-13.54), this result did not reach statistical significance, nor were they less likely to complete treatment (OR 0.69, 95% CI 0.07-6.67) than those with 99mTc-MDP negative scans. Uptake of 99mTc-MDP into extraosseous sites was also not associated with worse survival (HR 1.45, 95% CI 0.58-3.62) nor with decreased likelihood of completing treatment (OR 0.78, 95% CI 0.12-5.09). Other than indicating disease stage, these results do not support the hypothesis that the scintigraphic appearance at diagnosis confers prognostic information in children with advanced neuroblastoma.

Bone Neoplasms↗
PubMed1993

Hepatobiliary scintigraphy in a pediatric population: determination of hepatic extraction fraction by deconvolution analysis.

A study was performed to assess the feasibility of measuring the hepatic extraction fraction (HEF) and hepatic half clearance time (HCT) in pediatric patients with a variety of hepatobiliary diseases. There were 45 children categorized into four groups: normal 12; obstruction 9; hepatocellular disease (HCD) 16 and miscellaneous 8. In the normal patients, the mean HEF was 99% +/- 3.6% and the HCT was 23.6 +/- 7.7 min. In the two disease categories, hepatocellular disease and obstruction, there was a wide range of HEF 15%-84% and 25%-100%, respectively. This reflected the varying degrees of liver dysfunction and/or cholestasis. The average results of HEF for the HCD group was significantly lower than controls, and the greatest difference of the HCD group and other disease groups was with the miscellaneous group. This was not, however, different from the obstructive group. There was, however, a large overlap of results, and differentiation between the disease groups was not possible. HCT from the disease groups also showed a prolonged average clearance when compared to normals, although this was not significant when the p value was adjusted for multiple comparisons. The normal HCT was 23.6 +/- 7.7 min, whereas the hepatobiliary disease groups ranged from 20 to 714 min. Again, there was considerable overlap of results in the disease groups. These functional parameters are feasible and applicable in the pediatric population.

Adolescent↗
PubMed1992

Breast uptake of Ga-67 in a neonate.

A 6-day-old baby boy showed concentration of Ga-67 citrate in both breasts and an abdominal neuroblastoma. The breast uptake was most likely caused by estrogen and prolactin production and passage from the maternal to the fetal circulation.

Abdominal Neoplasms↗
PubMed1992

Multifocal osteomyelitis in childhood. Review by radionuclide bone scan.

Multifocal osteomyelitis is considered an uncommon complication of acute osteomyelitis. Over a 3-year period, 136 infants and children who had a final diagnosis of acute osteomyelitis were reviewed, and multifocal osteomyelitis was detected in 27 (19%) patients. The major age peak of acute osteomyelitis was between 6 weeks and 3 years (46%). Two age peaks were found for multifocal disease-less than 6 weeks (38%), and 9 to 12 years (44%). Three patients with multifocal disease had septicemia and photon-deficient areas on bone scans. Another adolescent group had nonspecific bone and joint pain that in some cases persisted for more than 3 months and were finally diagnosed as multifocal osteomyelitis. Organisms were isolated in 15/27 (56%). Multifocal osteomyelitis is well recognized in the neonatel age group. However, it occurs more commonly than previously described in older patients. This higher incidence can most likely be attributed to the higher use of the radionuclide bone scan early in the disease and the high sensitivity of the scan for the detection of osteomyelitis.

Acute Disease↗
PubMed1992

Pott's puffy tumor. Scintigraphic findings.

The authors describe the scintigraphic findings of bone and Ga-67 imaging performed on three patients thought to have Pott's puffy tumor. Two patients did indeed have it, but the third patient's "puffy tumor" was a soft tissue abscess.

Abscess↗