Hallazgos de la gammagrafía ósea en pacientes con adenocarcinoma de próstata recién diagnosticado: relación con los niveles de antígeno específico prostático

Abstract

Although it has been suggested that bone scintigraphy (BS) may not be necessary in patients with prostate adenocarcinoma (PA) and normal prostate specific antigen (PSA) plasma levels, controversy still remains. The objective of the study was to evaluate the existing relationship between PSA plasma levels and BS findings in patients with a recently diagnosed PA in order to assess whether BS may be omitted on the basis of the PSA levels in these patients. The 475 patients (70+/-7 years old) consecutively diagnosed of PA between 1994 and 1998 in our institution made up the study population. PSA plasmatic levels were determined and BS was performed (body planar study after 99mTc-methyl diphosphonate 900 MBq administration) in all the patients. In 362 patients (76.2%), BS was negative, in 108 (22.7%) positive and undetermined in the remaining 5 patients (1.1%). The mean PSA level in the whole study population was 74+/-267 ng/ml (range 0.4-4.200) and was higher in patients with positive GO (218+/-512 vs 31+/-89, p<0,0001). As PSA increased, the rate of patients with positive BS was significantly higher, this being 0%, 16.4%, 9.7%, 14.0%, 31.0% and 48.3% in patients with PSA 4, 4.1-10; 10.1-20; 20.1-30; 30.1-40, and >40 ng/ml, respectively (p<0.0001). In patients with positive BS, the PSA levels were 20 and 10 ng/ml in 30.6% and 18.6% of the patients, respectively. According to our experience, there is a significant association between PSA plasma levels and the BS results in patients with recently diagnosed PA. However, a significant proportion of patients with bone metastasis have normal PSA levels, and therefore BS should be performed in all patients with recently diagnosed PA regardless of the PSA levels.