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J Lumbroso

Publications and source records attributed to J Lumbroso.

At least 55 records · Page 3Linked to original sources
PubMed1994

Processing by factor analysis of dynamic dual isotope studies using 99Tcm and 201Tl within a middle energy band. Evaluation in thyroid nodule malignancy.

Simultaneous investigations with two isotopes are currently restricted because of spectral overlap. The factor analysis of spectral and dynamic structures (FASDS) method is shown to achieve accurate spectral separation. In addition, it estimates underlying dynamic mechanisms. Twenty-six patients were injected simultaneously with 99Tcm-pertechnetate and 201Tl-chloride to assess the malignancy of solitary thyroid nodules. List-mode acquisition of spectral, temporal and spatial coordinates of events allows the reconstruction of an image sequence indexed by time and energy. FASDS proceeds in two steps. First it yields both dynamic and spatial information related to each isotope (99Tcm and 201Tl) and partially removes the scatter component. Then it estimates the underlying kinetics and associated spatial distributions of each isotope. Using the 201Tl component, an index was derived from the uptake ratio between nodules and normal thyroid tissue. Concerning the detection of malignant nodules the method indicated no false negative in our limited group of 26 patients. One false positive result was found which could not be classified by the investigation of the 201Tl dynamic components contained in the reconstructed 201Tl factor sequence.

Factor Analysis, Statistical↗
PubMed1994

Refining interpretation of MIBG scans in children.

UNLABELLED: In pediatrics, the distribution of radioiodinated metaiodobenzylguanidine (MIBG) has been studied primarily in neuroblastoma. However, normal patterns in children show a number of particularities and pitfalls related to the context of pediatric oncology which must be identified. METHODS: We report on 28 equivocal scans in 24 children. In all cases, two experienced observers judged the scans to be equivocal and the definite interpretations were confirmed by follow-up. RESULTS: Difficulties in interpreting the scans were observed at the level of the thorax (15 patients), the abdomen (5 patients), the head (4 patients) or elsewhere (4 patients). The final interpretation of the scans was attributed to an unusual physiological pattern linked to age (9 patients), tumoral context (17 patients) or artifacts (2 patients). CONCLUSIONS: A number of important physiological areas of uptake in soft tissues can lead to false-positive interpretations of normal scans, such as the physiological upper thoracic uptake which has never been previously described. Numerous technical and physiological possibilities exist and those pitfalls must be ruled out. A precise knowledge of these technical difficulties and physiological variants can reduce the number of equivocal MIBG scans.

3-Iodobenzylguanidine↗
PubMed1993

Usefulness of technetium-99m hydroxymethylene diphosphonate scans in localizing bone metastases of differentiated thyroid carcinoma.

Iodine-131 is uniquely able to demonstrate iodine uptake of differentiated thyroid carcinoma (DTC), but precise localization may be difficult, especially in the thorax, due to the quality of image resolution with 131I and the lack of anatomical landmarks. When bone metastases do not show radioiodine uptake bone scintigraphy can be used to detect them. We studied two groups of patients. In group 1, 15 patients with known bone metastases of DTC were treated with 3.7 GBq 131I. After 4 or 5 days, technetium-99m hydroxymethylene diphosphonate (HMDP; 740 MBq) was injected and a whole-body scan with simultaneous acquisition of 131I and 99mTc-HMDP images was carried out using a large field of view gamma camera fitted with a high-energy collimator. Technetium uptake was abnormal in 47 of 63 localizations, being increased in 29 foci, decreased in 7 and heterogeneous in 11. The superimposition of 131I and 99mTc-HMDP scans permitted an accurate localization in 80% of spine metastases and in 46% of osseous thoracic localizations, even in the presence of lung metastases. In group 2, 9 patients, who had bone pain, neurological signs or elevated serum thyroglobulin, had DTC bone metastases without iodine uptake. They received a diagnostic dose of 99mTc-HMDP 3h prior to scintigraphy with a large field of view gamma camera fitted with a low-energy collimator. Technetium uptake was abnormal in 37 of 38 localizations, being increased in 34 foci and decreased in 3. One false-negative was found in a skull metastasis. In both groups of patients, 99mTc-HMDP scans were useful.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma, Follicular↗
PubMed1993

Factor analysis as a means of determining response to chemotherapy in patients with osteogenic sarcoma.

The prognosis of localized osteogenic sarcoma (OS) has improved considerably since the introduction of neoadjuvant chemotherapy. However, there is a subset of patients who do not show full benefit from neoadjuvant chemotherapy because of chemoresistance. The early identification of poor responders to chemotherapy during neoadjuvant therapy remains difficult. In order to evaluate the role of bone scintigraphy we report our experience of dynamic technetium-99m hydroxymethylene diphosphonate bone scintigraphy in 19 cases of paediatric osteogenic sarcomas. Before the beginning of chemotherapy, a dynamic scan was recorded during 30 min followed by static images at 3 h. The procedure was repeated halfway through the course of chemotherapy (6th week). Histological grading of the response to chemotherapy was carried out in the 12th week, showing nine good responses and ten poor responses. Factor analysis of dynamic structures (FADS) applied to dynamic scans allowed us to identify three factors termed vascular, "soft tissue" and osseous factors. The effect of chemotherapy on each factor was evaluated. Using FADS we were able to detect all the poor histological responders with the combination of vascular and osseous factors. Six out of nine good histological responders were also classified as scintigraphic responders. FADS applied to dynamic bone scans allowed us to identify at an early stage all the poor histological responders to neoadjuvant chemotherapy. This method may have clinical relevance for the therapeutic strategy in patients with OS.

Adolescent↗
PubMed1993

Intraoperative detection of pheochromocytoma with iodine-125 labelled meta-iodobenzylguanidine: a feasibility study.

We evaluated the feasibility of intraoperative detection of pheochromocytoma sites after injection of meta-iodobenzylguanidine labelled with iodine-125. Six patients with multiple or recurrent pheochromocytoma were injected for intraoperative detection. During surgery, all count rates were recorded using a CdTe detector diode. Tumour foci were found in all cases. Tumour count rates ranged from 50 to 1000 counts per second (mean approximately 400). Blood activity, used as a reference level, ranged from 10 to 50 counts per second (mean approximately 35). In all patients, the intraoperative probe was helpful to the surgeon and facilitated the discovery of the pathological foci even when they were small (< or = 1 cm). Complete resection under probe control was correlated with postoperative normalization of urinary normetanephrine excretion. The use of a probe designed to detect low-energy gamma-ray radionuclides bound to a highly specific molecule provides an accurate detection tool which is well adapted for ectopic localizations and for small foci.

3-Iodobenzylguanidine↗
PubMed1993

Bone metastases as the presenting manifestation of rhabdomyosarcoma in childhood.

Rarely, rhabdomyosarcoma can present with bone pain and bone lesions on radiographs without evidence of a primary tumor. Of 428 children with biopsy-proven rhabdomyosarcoma, four presented with radiographic evidence of bone metastases, but no primary tumor was found on subsequent evaluation. On radiographs, these metastases, located most commonly in the metaphyses of the extremities and in the spine, displayed a destructive or diffusely permeative pattern without sclerotic margins and mimicked the more common neuroblastoma. One patient also had diaphyseal cortical lytic metastases of the tibia. Radiographs defined metastases of the extremities better than the correlative bone scans. In the spine, on T2-weighted magnetic resonance (MR) images, metastases displayed high signal intensity which contrasted with the low-signal-intensity marrow in these pediatric patients. On histopathologic examination, metastatic rhabdomyosarcoma was composed of small cells of variable size, shape, and growth pattern similar to other round cell tumors. A positive desmin immunohistochemical test helped to establish the diagnosis. The radiologist, pathologist, and clinician should be aware of this unusual presentation of rhabdomyosarcoma so that suitable immunohistochemical tests are performed and appropriate chemotherapy given.

Adolescent↗
PubMed1993

Potential contribution of 131I-labelled monoclonal anti-CEA antibodies in the treatment of liver metastases from colorectal carcinomas: pretherapeutic study with dose recovery in resected tissues.

20 patients with liver metastases from colorectal carcinoma undergoing laparotomy received 15-60 mg intravenously, either intact or fragments of, anti-carcinoembryonic antigen (anti-CEA) monoclonal antibodies labelled with 0.55-1.48 GBq (15-40 mCi) of 131I, 3-8 days prior to operation. The uptake measured per gram of metastases ranged from 0.33 to 6.6 x 10(-3%) of injected dose. Tumour to liver uptake ratios ranged from 2 to 33. The radiation dose, estimated in 6 patients (3 of each group), for an extrapolated dose of 3.7 GBq (100 mCi) of 131I ranged from 0.3 to 0.8 Gy in normal liver or spleen (an acceptable estimate for bone marrow radiation dose) and from 3.4 to 8.2 Gy to the hepatic metastases, indicating that probably other therapeutic modalities should be associated with radioimmunotherapy.

Antibodies, Monoclonal↗
PubMed1992

Malignant pheochromocytoma: clinical, biological, histologic and therapeutic data in a series of 20 patients with distant metastases.

Twenty patients, 16 males and 4 females, aged 11-76 yr, were treated for a metastatic pheochromocytoma at our institution between 1985 and 1990. A neurofibromatosis was associated in 4. Thirteen patients had a unilateral adrenal tumor, 3 had an extraadrenal retroperitoneal tumor, 2 had a bilateral adrenal pheochromocytoma, one had a unilateral tumor with a contralateral medullary hyperplasia and one an adrenal and an extraadrenal pheochromocytoma. Metastases occurred in all patients, at presentation in 11, 10 to 30 months later in 7, and 9 and 28 yr later, respectively in two. Histology did not afford conclusive evidence for malignancy. Catecholamine hyperproduction was present in all, predominantly affecting norepinephrine. Neuron Specific Enolase level was elevated in 11, Neuro-Peptide Y level in 9 and procalcitonin level in 11/18. High dopamine, methoxytyramine and homovanillic acid excretion levels seemed to correlate with large tumors or terminal stage. MIBG uptake was found in 16 after a diagnostic dose and in 1 only after a therapeutic dose. Surgery was performed on primary tumor in 18 and on distant metastase in 10. Iodine-131 MIBG therapy was performed in 11, among whom 9 were evaluable. Cumulative activity ranged from 100 to 711 mCi, in 1 to 6 courses. Symptomatic improvement occurred in 5 patients, stabilization was observed in 3 and tumor partial response in two, which lasted for 28 and 9 months, respectively terminating in a rapidly progressing disease with bone marrow involvement. Moderate myelosuppression occurred in 4 patients. Chemotherapy gave no response in 7 evaluable patients. Fourteen patients died with a median survival of 16 months from diagnosis of metastases (range 3-60). Response to therapy was poor and warrants further cooperative trials.

3-Iodobenzylguanidine↗
PubMed1992

[How can metastatic bone involvement be assessed?].

The first intention imaging modality for detecting bone metastases of non small cell (NSC) bronchogenic carcinoma is bone scintigraphy using technetium-99m pyrophosphate or diphosphonates. This test has a high sensitivity but equivocal images may lead to complementary tests including magnetic resonance imaging (MRI) or bone biopsy. Based on bone metastases prevalence, scintigraphy is recommended for patients entering a therapeutic trial, having bone pain, having a non characteristic bone abnormality on radiography or CT, having a non epidermoid histology or having associated pathologies increasing the risk of surgery. The utility of bone scan is questionable for patients having a Stage I or II epidermoid cancer, having already evidence of bone metastases or for whom the result of the bone scan will not change the therapeutic management. After a negative bone scan, there will be probably an indication for MRI at search of small infra-scintigraphic osteo-medullary metastases.

Bone Neoplasms↗
PubMed1991

A new immunoradiometric assay (IRMA) system for thyroglobulin measurement in the follow-up of thyroid cancer patients.

A new commercially available kit for thyroglobulin (Tg) measurement [immunoradiometric assay (IRMA) system based on monoclonal antibodies] was used in 479 patients with thyroid carcinoma. The effective working range was 1 ng/ml, and results were strongly correlated with our homemade radioimmunoassay (RIA). This IRMA method is less susceptible to interferences of auto-antibodies than our RIA. During thyroxine (T4) treatment, the Tg level was undetectable in 98% of patients after total thyroid ablation, in 91% after total thyroidectomy and in 42% after lobectomy only. In this situation, Tg was found in all patients with large metastases and in 88% of those with small metastases. Following T4 withdrawal, Tg was detectable in all patients with neoplastic disease and in 13% of those in complete remission after total thyroid ablation. In conclusion, Tg measured with this IRMA method appears to be a reliable marker of differentiated thyroid carcinoma.

Follow-Up Studies↗
PubMed1991

Prognostic factors in patients with liver metastases from colorectal carcinoma treated with discontinuous intra-arterial hepatic chemotherapy.

48 patients with colorectal cancer metastatic to the liver were implanted with a subcutaneous access system allowing hepatic intra-arterial perfusion. Regional chemotherapy used 5-fluorouracil, while 17 patients also received low-dose mitomycin at the beginning of the study. Responses to the treatment occurred in 29 patients (60%) and median survival was 14.4 months. Toxicity included gastroduodenal erosions in 12.5% of the patients, leucopenia in 20.8%, catheter thrombosis in 42% and arterial thrombosis in 50%. 2 patients died of digestive haemorrhage probably related to treatment. When individually analysed, four factors were found to significantly affect survival: presence of hepatomegaly (defined as palpable liver edge exceeding the right costal margin by more than 5 cm) (P = 0.006), percentage of hepatic replacement superior to 50% (P = 0.003), more than four metastases (P = 0.025) and hypovascularised metastases at radionuclide liver scan with 99m technetium-labelled macroaggregate albumin (MAA) (P = 0.04). The effect of the four variables on the observed survival time was analysed using a Cox regression model. Two variables were found to have simultaneously influenced survival. Presence of hepatomegaly emerged as the more significant (P = 0.0001), the other being hypovascularised metastases at 99mTc-MAA.

Adenocarcinoma↗
PubMed1991

Use of m-[131I]iodobenzylguanidine in the treatment of malignant pheochromocytoma.

The efficacy and safety of m-[131I]iodobenzylguanidine ([131I]MIBG) were assessed in 15 patients with malignant pheochromocytomas in a nonrandomized, single arm trial, in which patients were treated with [131I]MIBG (SA, 740 megabequerel/mg) every 3 months. Seven of these patients had bone and soft tissue metastases, 4 had only soft metastases, and 4 had only bone metastases. The follow-up period ranged from 6-54 months; the number of doses ranged from 2-11, with 2.9 (78.4 mCi) to 9.25 gigabequerel (GBq) (250 mCi)/administration and a cumulative activity from 11.1-85.90 GBq (300-2322 mCi). The absorbed cumulative dose in tumors ranged from 12-155 Gy. A beneficial effect of the treatment was observed in 9 patients (60%). No complete remission of the disease was observed. Seven patients died during the study, among whom 4 never responded to the treatment. Seven had hormonal responses (4 complete and 3 partial), with a duration ranging from 5-48 months. Among these patients, 4 relapsed, and 3 died within 3 months. Five patients had partial tumoral responses mainly located in soft tissues and for a duration ranging from 29-54 months. All patients with a hormonal response had objective improvement in clinical status and blood pressure. There was no clear-cut relationship between the cumulative dose and the responses. The main side-effect observed in 1 patient with widespread bone metastases after three doses (12.9 GBq) was a pancytopenia, which resolved after treatment was discontinued. This study suggests that repeated [131I]MIBG treatment could be effective in patients with advanced malignant pheochromocytoma.

3-Iodobenzylguanidine↗
PubMed1989

Intra-arterial hepatic chemotherapy for metastatic liver from colo-rectal carcinoma origin.

Loco-regional intra-arterial chemotherapy of hepatic metastases from colo-rectal cancer is one of the most effective non-surgical treatments in this clinical situation. In our experience of 58 cases treated during 3 years, in a non randomized study by either: 1) discontinuous perfusion of 5FU (using a subcutaneous access) or 2) by continuous infusion of FUDR (using an implantable pump), we observed an objective response rate of 52% and 53% with a 1 year survival of 73% and 90%, respectively. This technique, however, is limited in its application by loco-regional complications and in its long term efficacy by the development of extrahepatic metastases. The proof of its efficacy in terms of survival prolongation, is being studied within the framework of a prospective randomized trial with a control group.

Adenocarcinoma↗
PubMed1989

[Imaging of malignant tumors of the uterus and ovary].

Authors discuss the role of new imaging methods in the management of malignant tumors of the ovaries and uterus. After briefly reviewing the imaging methods and particularly lymphangiograms, they discuss the value of these techniques for each tumor. The indications of these techniques detailed in the last chapter.

Diagnostic Imaging↗
PubMed1989

[Gastroduodenal complications of hepatic intra-arterial chemotherapy of hepatic metastases of colorectal origin].

Fifty-eight patients with colorectal liver metastases were treated by intra-arterial hepatic chemotherapy (IAHC) containing 5 FU (n = 42) or FUDR (n = 16). Twenty-three patients (39.6 p. 100) complained of abdominal pain. In three of these patients, the course was complicated by digestive hemorrhage. Endoscopic explorations and angioscintigraphy were normal in 4, showed oesophagitis in 3, superficial gastritis or duodenitis in 8 (34.7 p. 100) and gastric (2) or duodenal ulceration (6) in 8 (34.7 p. 100). The duodenal ulceration was extensive and considered to be cause of hemorrhage in two cases. Duodenal perforation due to the catheter was discovered in two other cases, one of which was secondary to tumoral extension revealed by forceps biopsy. This patient died 3 months later. Surgical treatment was mandatory in the other case due to digestive hemorrhage but did not prevent death. Angioscintigraphy performed in 15 patients with gastroduodenal inflammation or ulceration was normal in 7 patients, revealed arterial thrombosis in 5 and an extra-hepatic perfusion in the gastroduodenal area in 3 : this was related to a small pyloric artery which was occluded secondarily. IAHC was continued there after. This experience underlines the importance of exploring patients with digestive symptoms during IAHC so that it may be temporarily discontinued while an inadequately positioned infusion catheter may be corrected should gastroduodenal ulceration occur.

Antineoplastic Agents↗