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H G Heinze

Publications and source records attributed to H G Heinze.

At least 19 recordsLinked to original sources
PubMed1992

[The value of a new IRMA for determining thyroglobulin].

A total of 277 patients suffering from differentiated thyroid carcinoma with individual follow-up periods of up to five years had been investigated. More than 1,000 sera were collected. The present paper reports on the results of the parallel serum Tg determinations by means of a recently introduced Tg-IRMA system in comparison with the previously used, well established Tg-RIA method. The intra- and the interassay variation of the IRMA were found at 37% and 46%, respectively, for 4 ng Tg/ml, and 3% and 6%, respectively, for Tg values above 40 ng/ml. Several effects that could interfere with the serum Tg determination (freezing or repeated freezing and thawing of sera, hemolysis or lipemia or dilution of sera, preanalytical use of serum separating tubes) were examined. Although statistically significant in some instances, at least, all of the above mentioned effects were without any practical relevance for the clinical routine use of the IRMA. In patients being in complete remission and on complete TSH suppressive thyroid hormone treatment but having no residual thyroid tissue (n = 70), the level of clinical significance was 1 ng Tg/ml for the IRMA system, resulting in a sensitivity of 99% and a specificity of 90%, respectively. For the RIA system, however, the level of clinical significance was found to be 10 ng Tg/ml with a sensitivity of 89% and a specificity of 95%. We could additionally define the grey-zone for the practical use of the IRMA (1-3 ng Tg/ml). The IRMA system is significantly more sensitive and detects more sera correctly positive than the Tg-RIA.(ABSTRACT TRUNCATED AT 250 WORDS)

Follow-Up Studies↗
PubMed1992

Late cervical lymph node recurrence in differentiated thyroid carcinoma. An inherent problem of 131I beta dose distribution in small tumor deposits?

In differentiated thyroid carcinoma, postoperative radioiodine therapy is an undisputed element of the integral therapeutic concept. Sometimes, however, and years after initial diagnosis and therapy, cervical lymph node metastases occur without any evidence of local relapse or distant metastases, indicating that radioiodine therapy has not achieved definite tumor cell sterilization. A Monte Carlo computer simulation of the spatial energy dose distribution of 131I in small functioning tumor manifestations was performed to explain this phenomenon. It appeared that only a small fraction of the total beta-energy dose can be deposited inside the tumor if the latter becomes smaller than 1 mm in diameter: for tumors with homogeneous 131I uptake and diameters of 1.0, 0.5, 0.2, 0.1, 0.05 and 0.02 mm, this value does not exceed 86, 73, 39, 16, 8 and 4%, respectively. These data suggest a potential therapeutic gap for small tumor manifestations not apparent at the time of initial diagnosis and could explain the occasional occurrence of late cervical lymph node metastases.

Combined Modality Therapy↗
PubMed1991

[The 32P-test in the diagnosis of intraocular melanoma--an obsolete study method?].

Results of the 32P uptake test for the diagnosis of choroidal melanoma in 41 patients are reported. The sensitivity was 80%, the specificity 86%, if a count rate ratio of more than 1.4 between tumor and normal tissue was considered as pathological. Ratios between 1.4 and 1.6 ought to be considered as equivocal in which case specificity increases to 90%. The 32P uptake test still remains a method of clinical relevance in the diagnosis of choroidal melanoma.

Choroid Neoplasms↗
PubMed1991

[Radiotherapy of glioblastoma: is shortening of the treatment time justifiable?].

Survival of glioblastoma patients can be double by postoperative radiation but nevertheless rarely exceeds one year. It is therefore desirable to minimize treatment time and hospitalisation. Aim of our study is to investigate the feasibility of a reduction of treatment time by accelerated fractionation. Out of 110 patients treated for glioblastoma from 1975 to 1988 in our institution postoperative radiation was performed in 79 patients using three different fractionation schedules: 60 Gy in six weeks, single fractions 2 Gy (n = 38), 35 Gy in two weeks, single fractions 3.5 Gy (n = 27), 45.5 Gy in 2.5 weeks, single fractions 3.5 Gy (n = 14). No statistically significant differences in both the mean overall and disease free survival were evaluated between the three groups. The larger fraction size was well tolerated and no relevant increase of early or late adverse reactions occurred. As the duration of treatment can be reduced from six to two weeks, this accelerated fractionation schedule seems to be a reasonable alternative to conventional fractionation.

Adult↗
PubMed1991

[Postoperative external radiotherapy of differentiated thyroid carcinoma: when is radioiodine therapy alone inadequate? The dosimetric considerations with a Monte Carlo simulation].

Indication for postoperative external radiation of differentiated thyroid cancer has remained an issue of controversial discussion and is generally restricted to those cases where local tumor control by I-131 therapy alone seems doubtful. This may be the case when lymph node metastases are present or occult micrometastasis are suspected, as the beta(-)-radiation caused by the incorporated I-131 may be deposited partly outside the tumor. This problem of dose distribution is analysed in a simulation model by Monte Carlo techniques where tumors are tissue equivalent spheres of various size (r = 20 microns to 2 cm). Homogeneous I-131 distribution in the whole tumor volume (a) is analysed as well as peripheral deposition confined to the tumour surface (b). In tumors of r = 0.5 mm or less, the percentage of the total dose deposited inside the tumor rapidly decreases, r = 20 microns: 4.1% (a) and 0.9% (b), respectively. Furthermore, extensive dose inhomogeneities appear in tumors of similar sizes. As in local lymph node metastases tumoricidal radiation doses are not necessarily achievable by I-131 therapy alone, postoperative external radiation should be taken into account in the above mentioned clinical situations.

Combined Modality Therapy↗
PubMed1991

[The place of 99mTc-MDP skeletal scintigraphy in neuroblastoma. Is a new assessment necessary?].

The present study compares the reliability of MIBG and MDP bone scans in detecting bone metastases of neuroblastoma. Out of 57 patients, 23 had both 99mTc-MDP and 123I/131I-MIBG scans within a 2-week period. In 10 patients at primary diagnosis there was an underestimation of skeletal involvement by MIBG in 1/5, in 13 patients at follow-up in 3/9; 99mTc-MDP scans were able to visualize skeletal involvement in all those cases. There was only one false positive MDP scan. These results suggest that MIBG alone may fail to visualize skeletal involvement of neuroblastoma and should therefore be complemented by additional 99mTc-MDP scintigraphy.

3-Iodobenzylguanidine↗
PubMed1987

[Iodine-131 therapy of autonomous adenoma of the thyroid. 7-year results].

Between 1977 and 1984 a total of 301 patients with autonomous thyroid adenoma were irradiated with an individually calculated one-time dose of 400 Gy units of 131I. Repeated follow-up tests were made in 217 patients (up to 7.2 years, mean of two years). Pre- and post-treatment diagnosis in all patients consisted of determining T3 and T4, one TRH test, one 131I two-phase test to determine treatment, including quantified scintigraphy (under suppression, if necessary), as well as post-treatment scintigraphy and (post-treatment) 99mTc scintigraphy. The treatment was successful in 98% of patients; there was no difference between compensated and decompensated forms. Euthyroid state was achieved in 87% of patients, with typical findings of compensated T3 oversecretion, as is known to occur with endemic goiter in regions of iodine deficiency. The ability of the thyroid for autoregulatory adaptation to such iodine deficiency is thus preserved. Preclinical hypothyroidism occurred in 11% of patients: it could have been avoided in about half of them. Persistent or recurring autonomous adenoma was observed in 2% of patients as a result of under-dosage. One should thus aim at a dose of 400 Gy, to obtain optimal elimination. Radiation-induced carcinogenesis was not observed: radioiodine treatment and operation are thus of equal value in the causal treatment of autonomous adenoma. Radioiodine treatment is indicated in patients aged over 40 years with additional diseases and increased risk of anaesthesia and operation. It is preferred treatment if there are multiple autonomous adenomas.

Adenoma↗
PubMed1987

Extrathyroidal synthesis and biologic action of thyroid receptor antibody (TRAb) in Graves' disease.

In a patient with Graves' disease who underwent thyroidectomy with subsequent radioiodine therapy thyroid receptor antibody could be detected by radioligand assay. No thyroid tissue could be detected by 131I-scintiscanning. Thyroglobulin was repeatedly negative. Biologic activity of this patients serum could be demonstrated in the nude mice bio assay. 131I-incorporation and secretion of human thyroglobulin could be stimulated by injecting thymusdysplastic nude mice with transplants of thyroid tissue from a patient with Graves' disease with the athyroid patients serum. These results demonstrate evidence for extrathyroidal production and biological activity of TRAb in vivo.

Adult↗
PubMed1984

[131I-therapy of Basedow's disease and nonimmunogenic hyperthyroidism].

From 1977 to 1982, 315 patients suffering from thyrotoxicosis with diffuse and/or nodular goitre or Graves' disease were treated with 131I. In 246 patients, the results of treatment after 7 months to 5 1/2 years could be evaluated. After a single treatment with 131I, 72% of the patients with hyperthyroid nodular goitre and 61% of those with diffuse goitre, but only 36% of the patients with Graves' disease showed normal thyroid function. By repeated 131I treatments--as many as 5 for those with Graves' disease--normal thyroid function could be achieved in nearly all patients examined. Patients with immune thyrotoxicosis, type Graves' disease, showed a high resistance to therapy. A dependence was found between the results of these treatments and previous antithyroidal drug therapy or surgery. The rate of hypothyroidism varied between 4 and 15%. The highest rate of hypothyroidism was observed in operated patients with persistent or recurring thyrotoxicosis.

Graves Disease↗
PubMed1979

[Determination of the iodine content of the thyroid by means of fluorescence scans (author's transl)].

A procedure is described in which stable 127I in the thyroid is induced to fluorescence (28.5 keV) by 241Am (59.5 keV). The radiation is registered on a Si (Li) detector and can be used in order to obtain a scintigram or to determine the concentration of127I in the thyroid at any selected point. The apparatus is available commercially and has been adapted for use with a scanner. Measurements using collimation of 3.5 to 4 cm revealed a focus with a marked tomographic effect. The sensitivity of the apparatus was investigated by using solutions of varying iodine concentrations; calibration curves for determining iodine concentration in thyroid tissue were obtained. It is necessary to take account of the thickness of the thyroid gland and of the superficial tissues because of the marked attenuation of the radiation within the tissues. Radiation dose to the thyroid during the scintigram was about 0.1 mGy (10 mrd), i.e. about 5% of a conventional TC scintigram. There is no whole body irradiation.

Humans↗
PubMed1979

[Clinical result of thyroid scintigraphy and iodine estimations using a fluorescent technique (author's transl)].

The new technique of quantitative fluorescent scintigraphy was used for determining the regional distribution and concentration of stable intrathyroid iodine (127 I) in 96 patients. Average iodine concentration in normal people (20 individuals) without thyroid enlargement living in the Bavarian iodine-deficiency area was 0.38 +/- 0.07 mg/g. In 32 patients with simple goitres it was significantly lower at 0.17 +/- 0.06 mg/g. With this technique it was possible to separate two types of hyperthyroidism amongst 21 patients: those with low iodine concentration in the thyroid (0.15 +/- 0.08 mg/g) and those with high iodine concentration (0.42 +/- 0.12 mg/g) after iodine administration. The iodine concentration in decompensated autonomous adenomas in twelve patients was usually low (0.12 +/- 0.12 mg/g). On the other hand iodine concentration was high in the paranodular tissues and could be demonstrated on the fluorescent scintigram. The quality of the scintigram using this technique for concentrations below 0.1 mg/g is inadequate. In this situation good imates can be obtained by radionucleid scintgrams. The situation is reversed by previous administration of iodine.

Diagnosis, Differential↗
PubMed1979

[Growth rate of pulmonary metastases (author's transl)].

The growth of 148 untreated metastases to the lung was determined in 47 patients. Pulmonary metastases of squamous-cell carcinomas, sarcomas and malignant melanomas exhibited exponential growth, the doubling times were distributed log-normally, the geometric mean amounted to six weeks. The growth rate of adenocarcinomas decreased with increasing tumor size approximately in accordance with a Gompertzian function.

Adenocarcinoma↗
PubMed1977

[Lung function scintigraphy in the diagnosis of regional disturbances of ventilation (author's transl)].

Lung function scintigraphy is the method of choice for the diagnosis of regional ventilation disturbances. The aim of this study was to determine which of various parameters is the most reliable. Sensitivity of the 3-minute retension test is 96%, of the single breath 45%, equilibration 32% and of the ventilation index, only 28%. Sensitivity of the various parameters for demonstrating multi-focal ventilation abnormalities is 100% for the 3 minute retention test, 32% for single breath, 19% for equilibration and 21% for the ventilation index. The underlying basis for these findings is discussed and it is concluded that it is possible to simplify the technique when dealing with regional ventilation abnormality in obstructive airway disease, but not when dealing with other restrictive changes.

Airway Obstruction↗