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R A Wahl

Publications and source records attributed to R A Wahl.

At least 19 recordsLinked to original sources
PubMed1998

Prophylactic thyroidectomy in 75 children and adolescents with hereditary medullary thyroid carcinoma: German and Austrian experience.

When mutations of the RETproto-oncogene were found in 1993 to account for hereditary medullary thyroid carcinoma (MTC), surgeons obtained the opportunity to operate on patients prophylactically (i. e., at a clinically asymptomatic stage). Whether this approach is justified, and, if so, when and to which extent surgery should be performed remained to be clarified. A questionnaire was sent to all surgical departments in Germany and Austria. All of the patients who fulfilled the following criteria were enrolled: (1) preoperatively proved RET mutation; (2) age </= 20 years, (3) clinically asymptomatic thyroid C cell disease; and (4) TNM classification pT0-1/pNX/pN0-1/M0. Seventy-five patients were identified, and fifteen mutations were detected in six codons. Two adolescents had unilateral pheochromocytomas as part of the multiple endocrine neoplasia II (MEN-II) syndrome. No hyperparathyroidism was noted. All patients underwent total thyroidectomy, and 57 patients went on to have lymph node dissection. Parathyroid glands were removed in 34 patients and autografted in 11. Histopathology revealed MTC in 46 patients (61%, youngest 4 years); C cell hyperplasia (CCH) only was detected in the other 29 patients. Three patients had lymph node metastases (LNMs) the youngest being age 14 years. Calcitonin levels were not useful for differentiating between CCH and MTC, but in all patients with LNMs at least the stimulated calcitonin levels were assayed. After surgery, five patients (6.7%) sustained permanent hypoparathyroidism, and one patient (1.3%) had a permanent unilateral recurrent nerve palsy. All but three patients (96%) were biochemically cured. In conclusion, prophylactic total thyroidectomy can be performed safely in experienced centers. We recommend prophylactic total thyroidectomy at age 6. Cervicocentral lymph node dissection should be included when calcitonin levels are elevated or if patients are older than 10 years. Bilateral lymph node dissection should be performed if LNMs are suspected or when patients with elevated calcitonin are older than 15 years.

Adolescent↗
PubMed1998

Differentiated operative therapy of thyroid autonomy (Plummer's disease).

The operative therapy of the autonomous thyroid deals almost exclusively with nodular goiters. There are only rare situations with purely diffuse autonomy in surgical patients. The endpoint of operative therapy is permanent elimination of clinically relevant autonomous function and thereby irreversible abolition of thyrotoxicosis, even in their latent form. Clinically relevant autonomous function normally ist linked to nodular structures of different size and different distribution, so that this aim corresponds automatically with the aim of complete removal of nodular structures, both in autonomous and in non-autonomous goiters. Function is best preserved by leaving a homogenous remnant of considerable size. In different particular clinical situations (for example pregnancy, suspicion of malignancy, recurrent goiter, intrathoracic goiter, thyrotoxic crisis, Marine-Lenhart-syndrome) the basic principal of operative strategy is varied according to the respective situations. Unsatisfactory operative results are mainly caused by incomplete removal of nodules, based on insufficient surgical performance of morphological and functional diagnostics, which is related to operative uniformity. An operative strategy, which ist "fitted to morphology" and "regarding function" and which we call "selective strategy", in our opinion ist highly appropriate, to avoid remnant nodules and remnant autonomy and to preserve an normal remnant, even in different position and of different size. This selective surgery ist applicable both to autonomous and non-autonomous goiter. Compared with the classic subtotal, uniform procedure the incidence of remnant nodules is reduced from about 50% to about 5 %. Remnant autonomy is almost excluded, when mistakes are avoided (about 1%). The incidence of recurrent goiter and recurrent thyrotoxicosis is lowered to under 5%--but up to now there are too few reliable long-term follow-up studies. The selective surgery strategy demands flexibility regarding operative tactics, which can be simply classified into 5 basic situations, which we relate to the operative procedure per thyroid lobe. It requires experience and competence in carefully dissecting and--when necessary--manipulating the recurrent laryngeal nerve und the parathyroid glands. Under these conditions it is followed by a comparatively low rate of complications (permanent recurrent laryngeal nerve paralysis and hypoparathyroidism under 1%, respectively). Thus, the old dilemma of thyroid surgery can be solved, which consists of radical operation with higher morbidity and lower frequency of recurrent disease on the one hand and more limited operative procedures with fewer complications but more frequent recurrencies on the other hand.

Female↗
PubMed1998

Office laboratory procedures, office economics, patient and parent education, and urinary tract infection.

This review provides an update on four areas of office practice: office laboratory procedures, office economics, patient and parent education, and urinary tract infection. Thomas Ball reviews physician office laboratories, with updates on the Clinical Laboratory Improvement Amendments, office proficiency testing, and office testing for streptococcal pharyngitis and Helicobacter pylori. Eve Shapiro reports on office economics, focusing on the influence of managed care on pediatric practice. Burris Duncan provides a review of the new National Institutes of Health asthma guidelines, and challenges us to become more involved in patient education. Richard Wahl reviews urinary tract infections, vesicoureteral reflux, dysfunctional voiding, and appropriate imaging studies. Our approach is to provide pediatricians with useful and practical information for their office practices.

Asthma↗
PubMed1998

[Differentiated thyroid gland carcinoma p-T2/T3--extent of lymphadenectomy].

Systematic lymphadenectomy, which is compartment-orientated, from central node dissection to (modified) radical neck dissection, is not controversial in cases with intra-operative macroscopic node involvement. General "prophylactic" dissection, at least of the ipsilateral central compartment, is advocated due to a high incidence of "occult", microscopic positive nodes, and the elevated risk regarding recurrency and survival which is connected to node-positivity, and lowered recurrence rates with systematic lymphadenectomy. Nevertheless, the biological impact of occult positive nodes, as an independent risk-factor, is not yet clear, with important differences between papillary and follicular carcinoma ("marker" or "governor" of the disease?). Enhanced operative morbidity by extensive lymphadenectomy, especially hypoparathyroidism, must be taken into account.

Adenocarcinoma, Follicular↗
PubMed1998

[Selective (= morphology and function dependent) surgery of nodular struma: relationship to risk of recurrent laryngeal nerve paralysis by dissection and manipulation of the nerve].

In a consecutive series of 1,143 first operations for benign nodular goiter with 1,928 "nerves at risk", the incidence of postoperative recurrent laryngeal nerve palsy (RLNP) was analyzed related to the extent of the operative procedure (node-excision up to lobectomy) and manipulation of the nerve (identification, mobilization, non-identification). The incidence of early RLNP increased with the extent of the operation (1.2% up to 4.8% in lobectomy) and with the extent of nerve manipulation (up to 3.1% in extensive mobilization). However, the rate of permanent RLNP was higher after non-identification of the nerve (0.6% vs 0%), especially in the group of conventional subtotal resection (1.3% vs 0%; p < 0.05). As a rule, the nerve should be identified, especially in conventional subtotal resection, when possible without further mobilizing manipulations.

Goiter, Nodular↗
PubMed1998

[Surgery of nodular goiter: postoperative hypocalcemia in relation to extent of resection and manipulation of the parathyroid glands].

In a series of 579 consecutive first operations for bilateral benign nodular goiter, the incidence of hypocalcemia was analyzed related to the extent of the bilateral operative procedure and manipulation of the parathyroid glands (identification, mobilization, non-identification). The incidence of early hypocalcemia increased with the extent of the operation and with increasing manipulation of the parathyroid glands. However, permanent hypocalcemia was exclusively found after identification of less than three parathyroid glands (1.5% vs 0%), most evidently after bilateral conventional subtotal resection (3.5%). As a rule, the parathyroid glands should be identified routinely, especially in conventional subtotal resections, if possible without further mobilizing manipulations.

Goiter, Nodular↗
PubMed1997

Office laboratory procedures, office economics, patient and parent education, and urinary tract infection.

This review provides an update on four important areas in office pediatrics: office laboratory procedures, office economics, patient and parent education, and urinary tract infection. Ball reviews new information about physician office laboratories, with updates on the Clinical Laboratory Improvement Amendments, streptococcal pharyngitis, urinalyses, office stool examination, and information on Helicobacter pylori serology. Shapiro reports on office economics, highlighting new office technologies, physician operated networks, managed care, recent legislation, and the "cost versus quality" debate. Duncan provides a very thought provoking essay on parent and patient education, focusing on improving parenting skills. Wahl reviews the recent literature on urinary tract infections, with emphasis on host-bacteria interactions, diagnostic evaluations, pyelonephritis, renal cortical scarring, and long term follow-up of vesicoureteral reflux. We hope we have provided pediatricians with useful and practical information for their office practices.

Child↗
PubMed1991

[Preventive operation of the thyroid gland].

Since the transformation of adenoma into carcinoma has not been proved, surgery of cold nodules cannot be classified as "prophylactic". Early treatment of differentiated carcinomas can, however, prevent transformation into anaplastic carcinoma. Prophylactic lymphnode dissection is of proven value only in C-cell carcinoma; C-cell hyperplasia in the hereditary type of this tumor is the only clearly prophylactic indication to total thyroidectomy. Hyperthyroidism in functional thyroid autonomy can be prevented in a euthyroid stage. The aim of prophylaxis against recurrent goiter and hyperthyroidism influences the operative strategy in both, immunogenous and non-immunogenous hyperthyroidism.

Diagnosis, Differential↗
PubMed1990

[What is the place of "selective thyroid gland resection" in surgery of benign nodular struma].

Remnants after "classic" Subtotal Thyroidectomy are of constant size in constant position. "Selective" thyroidectomy intends to remove all nodules, but to save normal tissue--irrespective of their localization. From July 1985 to Dec. 1989 in 48.5% of 1124 thyroid lobes sel. surgery was performed, in 27.8% subtotal, in 23.8% total lobectomy. Primary postop. recurrent lar. palsy occurred in 1.3% after sel., 1.0% after subt. and 2.7% after total lobectomy. 90% of primary r.l.n.p.'s were transient--after sel. lobectomy only one persistend (0.2%). Hypocalcemia: 0.7% after sel., 1.4% after subt. thyroidectomy. Besides better quality and quantity of remnants selective thyroidectomy is supported by low rate of complications.

Goiter, Nodular↗
PubMed1988

[Hormone active versus hormone inactive parathyroid gland cancer].

Problems regarding diagnosis and treatment of hormonally active and hormonally inactive parathyroid carcinomas arise from opposite sides, as is shown in two resp. cases. In functionally active tumors parathyroid origin is clear--but how to prove malignancy in early tumor stages? In inactive tumors malignancy is sound--but how to prove their parathyroid origin? Meticulous histologic examination (semithin-Layer) and cytophotometric DNA-measurement may be helpful diagnostic tools for active tumors, immunohistochemistry and analysis of parathormone fragments in plasma and tumor-cell-culture for inactive tumors. Nevertheless the surgeon's decision for radical surgery sometimes will have to be put on the intraoperative macroscopic situs--in order to provide curative treatment.

Adult↗
PubMed1988

[Reintervention in C-cell carcinoma].

Cervical re-exploration in persistent medullary thyroid cancer usually fails to normalize serum calcitonin levels, which is the most sensitive criterion of tumour-free status (2 out of 21 patients in our re-exploration series). Positive lymph nodes - even at an early tumour stage - seem much more important (postoperative normal serum calcitonin: 86% in the occult tumour group, 71% in patients with palpable primary tumour and negative lymph nodes, as opposed to only 18% with a palpable cervical mass and positive lymph nodes). However, local re-exploration in case of persistent medullary thyroid cancer seems to offer a possible curative chance for the control of recurrence, especially after inadequate primary surgery. In cases without visible distant metastases a marked reduction in serum calcitonin level may be expected (21% of the preoperative level for stages N1 and N2 and 16% for stage N3 on average). In patients with elevated calcitonin levels after stimulation as sole indicator of persistent tumour the indication for reoperation should be handled cautiously. Thus, in 3 out of 5 patients with occult medullary thyroid cancer diagnosed only on the basis of venous sampling who were subjected to multiple cervical re-explorations, distant metastases were subsequently found during follow-up.

Calcitonin↗
PubMed1987

[Surgery of metastases of differentiated thyroid cancers].

84 (19.5%) of 431 patients with differentiated thyroid cancer developed distant metastases in bone and parenchymal organs. 78% of primary bone metastases and only 21% of primary lung metastases were treated operatively. High survival rates of 33-60% at 5 years supported the necessity of surgical interventions primarily in bone metastases to prevent early morbidity due to pathological fractures. Even in case of questionable increase in survival rate surgery of metastases from differentiated thyroid carcinomas doubtlessly improves the quality of life in these patients.

Adenocarcinoma↗
PubMed1987

Nerve growth factor (NGF) sensitizes human medullary thyroid carcinoma (hMTC) cells for cytostatic therapy in vitro.

Medullary thyroid carcinoma (hMTC) cells were established from nine patients with MTC disease to initiate a new approach of adjuvant medical therapy in these patients. We measured calcitonin (CT) secretion, DNA synthesis, and cell proliferation in vitro and their response to various substances. Nerve growth factor (NGF) (0.01 to 10 micrograms/ml), glucagon (0.01 to 100 micrograms/ml), and isoproterenol (4 to 500 micrograms/ml) stimulated CT secretion and DNA synthesis in hMTC cells. Other substances, calcium (1.0 to 15 mmol), pentagastrin (1.0 to 50 mumol), dibutyryl-cyclic-adenosine-monophosphate (1.0 to 100 mumol), and phorbol ester TPA (1.0 to 100 nmol), stimulated CT secretion but not DNA synthesis. In addition, NGF enhanced cell proliferation of hMTC cells 2- to 3- fold and caused an increased sensitivity of these cells for chemotherapy in vitro. Thus 0.5 microgram/ml doxorubicin (half-maximal effective dose) induced a cell death rate of up to 32.8%, which was enhanced by preincubation with NGF to 68.1% (1.0 microgram/ml, NGF) and to 100% (10.0 micrograms/ml, NGF), respectively. Pulsative stimulation of APUD cell carcinomas with NGF may therefore improve the response rate of these tumors to chemotherapy, which would be of significant clinical importance for patients with residual postoperative MTC tissue.

Antineoplastic Agents↗
PubMed1985

Thyroid function after surgery for autonomous and non-autonomous nodular endemic goitre--effect of iodide-substitution.

The aim of this study was to evaluate the influence of postoperative iodide-substitution on the function of thyroid remnants of different quality and quantity in order to define the appropriate prophylaxis (iodide or thyroid hormone) to prevent recurrent goitre. In a prospective, randomized clinical trial, the following patients were examined: group I: simple, non-autonomous nodular goitre, bilateral thyroidectomy (n = 40); group II: simple, non-autonomous nodular goitre, "selective" (unilateral) thyroidectomy (n = 40); group III: autonomous nodular goitre, bilateral thyroidectomy (n = 40); group IV: autonomous nodular goitre, "selective" (unilateral) thyroidectomy (n = 35). The following parameters were measured 6 and 12 weeks postoperatively. Serum-total-T4, -T3, -TSH, TRH-test, 99mTc-Thyroid-Uptake (TcTU). Six weeks postoperatively the 4 groups were separately randomized into controls and treatment groups, who received 200 micrograms iodide/day orally. Six weeks postoperatively, patients in group I had lower T4 levels and both basal and stimulated TSH were higher than in the other groups, however no significant differences were observed in T3, T4/T3 ratio and TcTU. Twelve weeks postoperatively patients from groups I, II and III, who had been treated with iodide, had lower T3 and TcTU values but higher T4 and T4/T3 than the appropriate controls. Basal and stimulated TSH showed no differences between controls and iodide-treated patients in these groups. In group IV, T4 and T3 showed a tendency to elevation (n.s.), and basal and stimulated TSH as well as TcTU were lower in patients with iodide.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical Trials as Topic↗
PubMed1985

[Radicality principles in operations on malignant thyroid tumors].

Different concepts are required by different tumors: anaplastic carcinomas rarely are accessible to curative surgery, but tumor reduction gives sense in combined concepts. In follicular carcinomas general ("near"-) total thyroidectomy + radioiodine + hormonal suppressive therapy is recommended, with respect to the high incidence of distant metastases even in low 1 degree Tu-stages. Papillary carcinomas allow a stage related procedure with exceptions from total thyroidectomy: no reintervention for "occult" carcinomas and-in patients under 40 years of age-hemithyroidectomy for intrathyroid tumors without regional metastases. In C-Cell-carcinomas total thyroidectomy has to be accompanied by lymph-node dissections of various extent, depending on familiary or sporadic type and tumor-stage.

Adenocarcinoma↗