[Serum thyroglobulin and whole-body scanning as markers in the follow-up of differentiated thyroid carcinomas]. / La tiroglobina sérica y el rastreo corporal total como indicadores en el seguimiento del carcinoma diferenciado de tiroides.

We have compared two "markers" in the follow up of post treatment (surgery and therapeutical use of I-131) differentiated thyroid carcinoma. In 153 patients, thyroglobulin (Tg) serum levels were measured after withdrawal of I-thyroxine therapy, before performing a whole-body scan (WBS) with iodine-131; in 55 of these patients, Tg was measured again after at least 45 days of I-thyroxine treatment. The patients were followed between 3 and 10 years, and there were 2713 matched studies. Our results indicate for both parameters, false positive and negative values; sensitivity (SE) for WBS was 89% and specificity (SP) 83%; Tg presents a SE of 86% and SP of 83%. Matching both parameters, SE was 95% and SP 98%. The causes of false results are discussed. Tg determinations under I-thyroxine treatment do not permit the establishment of absence of illness; 37.7% of patients with demonstrated metastases or relapse showed negative Tg values that reached pathological values after suspension of I-thyroxine treatment; another 41.4% with elevated Tg values under therapy reached these values after suspension of I-thyroxine. Both markers, when utilized at the same time, offer the best possibilities in the follow-up of differentiated thyroid carcinoma, when determinations are carried out after suspension of hormonal treatment.

La tiroglobulina sérica y el rastreo corporal total como indicadores en el seguimiento del carcinoma diferenciado de tiroides / Serum thyroglobulin and whole-body scan as markers in the follow up of differentiated thyroid carcinomas

Hemos comparado el valor de los indicadores en el seguimiento del carcinoma tiroideo diferenciado (CaDT): tiroglobulina sérica (Tg) y rastreo corporal total con I-131 (RCT), que fueron realizados entre 3 y 10 años después del tratamiento quirúrgico más dosis terapéutica de I-131. Se realizaron en 153 pacientes 2713 estudios apareados, que se efectuaron con suspensión de la opoterapia por más de 30 días. En 55 pac. se realizaron determinaciones de Tg bajo opoterapia y en 18 en las mismas condiciones, determinaciones seriadas durante 6 meses. Los resultados indican que ambos parámetros pueden presentar falsos positivos y negativos, discutiéndose las razones de los mismos. La sensibilidad (S) para RCT fue de 89% y la especificidad (E) de 83% y para Tg S de 86% y E de 83%; si se consideran ambos parámetros en forma conjunta, S 95% y E 98%. La determinación de Tg bajo opoterapia no permite estabelecer la existencia de metástasis o recidivas con iguales posibilidades que luego de suspensión de la misma. El 37,7% de los casos con enfermedad demostrable, presentaron valores negativos de Tg bajo opoterapia que se elevaron a valores patológicos ...

La tiroglobina sérica y el rastreo corporal total como indicadores en el seguimiento del carcinoma diferenciado de tiroides. / [Serum thyroglobulin and whole-body scanning as markers in the follow-up of differentiated thyroid carcinomas]

We have compared two [quot ]markers[quot ] in the follow up of post treatment (surgery and therapeutical use of I-131) differentiated thyroid carcinoma. In 153 patients, thyroglobulin (Tg) serum levels were measured after withdrawal of I-thyroxine therapy, before performing a whole-body scan (WBS) with iodine-131; in 55 of these patients, Tg was measured again after at least 45 days of I-thyroxine treatment. The patients were followed between 3 and 10 years, and there were 2713 matched studies. Our results indicate for both parameters, false positive and negative values; sensitivity (SE) for WBS was 89

and specificity (SP) 83

; Tg presents a SE of 86

and SP of 83

. Matching both parameters, SE was 95

and SP 98

. The causes of false results are discussed. Tg determinations under I-thyroxine treatment do not permit the establishment of absence of illness; 37.7

of patients with demonstrated metastases or relapse showed negative Tg values that reached pathological values after suspension of I-thyroxine treatment; another 41.4

with elevated Tg values under therapy reached these values after suspension of I-thyroxine. Both markers, when utilized at the same time, offer the best possibilities in the follow-up of differentiated thyroid carcinoma, when determinations are carried out after suspension of hormonal treatment.

La tiroglobulina sérica y el rastreo corporal total como indicadores en el seguimiento del carcinoma diferenciado de tiroides / Serum thyroglobulin and whole-body scan as markers in the follow up of differentiated thyroid carcinomas

Hemos comparado el valor de los indicadores en el seguimiento del carcinoma tiroideo diferenciado (CaDT): tiroglobulina sérica (Tg) y rastreo corporal total con I-131 (RCT), que fueron realizados entre 3 y 10 años después del tratamiento quirúrgico más dosis terapéutica de I-131. Se realizaron en 153 pacientes 2713 estudios apareados, que se efectuaron con suspensión de la opoterapia por más de 30 días. En 55 pac. se realizaron determinaciones de Tg bajo opoterapia y en 18 en las mismas condiciones, determinaciones seriadas durante 6 meses. Los resultados indican que ambos parámetros pueden presentar falsos positivos y negativos, discutiéndose las razones de los mismos. La sensibilidad (S) para RCT fue de 89% y la especificidad (E) de 83% y para Tg S de 86% y E de 83%; si se consideran ambos parámetros en forma conjunta, S 95% y E 98%. La determinación de Tg bajo opoterapia no permite estabelecer la existencia de metástasis o recidivas con iguales posibilidades que luego de suspensión de la misma. El 37,7% de los casos con enfermedad demostrable, presentaron valores negativos de Tg bajo opoterapia que se elevaron a valores patológicos ... (AU)

Technetium-99m APD compared with technetium-99m MDP as a bone scanning agent.

We have investigated the possibilities of technetium-99m-(-3-aminohydroxypropylidene)-1-1-bisphosphon ate ([99mTc]APD) as a bone scanning agent in 14 normal subjects and 28 patients. Similar studies in the same normal subjects and patients were carried out with 99mTc-methylene-bisphosphonate ([99mTc]MDP). The compounds were labeled with 99mTc by means of an electrolytical method; the free pertechnetate content was always under 1%. The [99mTc]APD T1/2 of the third component of the disappearance plasma curve in six normal subjects was 152 +/- 46 min (mean +/- s.d.), while the 24-hr whole-body retention (WBR) was 17.6% +/- 4.6. The [99mTc]MDP value of the 24-hr WBR was 28.6% +/- 3.9 (p less than 0.001). The bone/soft-tissue ratio (B/ST) was investigated in eight control subjects on the eleventh thoracic and the fourth lumbar vertebrae. The B/ST ratios were similar for both APD and MDP studies. In 28 patients with suspected bone metastasis or primary bone disease, bone scintigraphy was carried out; both compounds showed similar findings and the same number of positive results. In five of these patients, the lesion/normal bone ratio was determined with values of 4.6 +/- 2.0 in APD studies and 4.8 +/- 2.3 with MDP. APD was also used in 126 patients; no adverse reactions were observed. The APD dose used i.v. for bone scanning was 200-fold less than those employed by mouth per day, for the treatment of bone disease for long periods. In our experience, APD appears to be an adequate agent for bone scintigraphy.