Stereotaxic needle core biopsy of breast lesions using a regular mammographic table with an adaptable stereotaxic device.

OBJECTIVE: Fine-needle aspiration and stereotaxic needle core biopsy (SNCB) are techniques used in the workup of breast lesions suggestive of cancer. Many surgeons are reluctant to rely on fine needle results, and until now, SNCB could be done only with a dedicated biopsy table. Our study was done to determine whether SNCB could be performed safely and effectively with a regular mammography unit and an added stereotaxic device. SUBJECTS AND METHODS: SNCB was performed on 254 patients by using a Siemens Mammomat 2 regular mammography table with an added stereotaxic device. Patients were referred from a breast screening center, a local tertiary care center, and from our own center. Patients who had unequivocal histopathologic evidence of a benign process (133 of 254 patients) did not undergo surgical biopsy and are being followed up mammographically. The remainder (121 patients) all had surgical biopsies. RESULTS: Sufficient material for histologic analysis was obtained in 249 (98%) of 254 cases. In 31 of 254 cases, sampling was problematic. This group comprised cases in which the patient moved within the compression device, the mammographic and histologic diagnoses were discordant, or calcifications were not present in the core sample when the indication for SNCB was the presence of microcalcifications. This group all had open biopsies. In 25 of 254 cases, the pathologic findings were suggestive of cancer. Cancer was detected in 11 of these cases on open biopsy. Of the 14 benign cases, 11 showed atypical features or ductal hyperplasia on open biopsy. Malignant tumor was diagnosed in 60 of 254 cases by SNCB. Corresponding malignant tumor was seen in 59 of 60 of the open biopsy specimens. CONCLUSION: The SNCB technique is not limited to use on a dedicated biopsy table but can be readily adapted to a regular mammography unit. It is a safe, reliable and cost-effective procedure that often spares the patient a surgical procedure.

Dissociation of phosphaturia and 25(OH)D-1 alpha-hydroxylase trophism using a novel analogue of parathyroid hormone.

Certain parathyroid hormone (PTH) analogues have been shown to selectively impair some but not all physiological actions of PTH. In this study, transaminated rat (r) PTH [TA-rPTH-(1-34)], a PTH analogue that differs from the rPTH-(1-34) fragment in that the NH2-terminal alanine is converted to pyruvate, was infused into mice to determine its properties in vivo and specifically to determine whether stimulation of 25-hydroxyvitamin D-1 alpha-hydroxylase (1 alpha-hydroxylase) activity was more dependent on concomitant renal handling of phosphate or on generation of adenosine 3',5'-cyclic monophosphate (cAMP). High-performance liquid chromatography-purified TA-rPTH-(1-34) was infused into C57BL mice at 10 or 30 pmol/h for 24 h. At 30 pmol/h, TA-rPTH-(1-34) was comparable with rPTH-(1-34) in its hypophosphatemic and phosphaturic effects but was less potent than rPTH-(1-34) in raising serum calcium. TA-rPTH-(1-34) was markedly less effective in stimulating renal 1 alpha-hydroxylase than rPTH-(1-34). Stimulation of urinary cAMP excretion occurred after infusion with TA-rPTH-(1-34), but this effect was significantly less than that seen with rPTH-(1-34). These findings indicate that PTH-induced hypophosphatemia and phosphaturia can be uncoupled from PTH stimulation of 1 alpha-hydroxylase. Furthermore, cAMP-related signal transduction appears to be more significant in regulation of 1 alpha-hydroxylase than mechanisms that mediate PTH-sensitive phosphate transport, independent of cAMP.

Quantitation of free sulfate and total sulfoesters in human breast milk by ion chromatography.

A method for the assay of free sulfate and total sulfoesters in human breast milk by ion chromatography is described. After incubation in 1 M hydrochloric acid at 95 degrees C for 90 min, hydrolytic cleavage of sulfoester standards was essentially complete. The increase in free sulfate after hydrolysis was used as a measure of total acid-labile sulfoesters. We found that this fraction [222 +/- 16 mumol/l (mean +/- standard error), n = 29] comprised 87% of the total sulfate in mature milk. Free sulfate (35 +/- 3 mumol/l) therefore makes only a small contribution to the total sulfate pool available to human infants.

The effect of adenosine and adenosine analogues on methylxanthine-induced hypercalciuria in the rat.

The chronic effects of dietary caffeine, theophylline, and theobromine on urinary calcium excretion were investigated in the adult male rat. The effect of acutely administered adenosine and adenosine analogues on methylxanthine-induced hypercalciuria was concurrently investigated. When rats were fed equimolar amounts of theobromine, caffeine, and theophylline, it was found that urinary calcium excretion increased; on day 7 values were increased over controls (p less than 0.05) by 54, 146, and 208%, respectively. On day 20, an injection of adenosine reduced calcium excretion in methylxanthine-treated rats to levels not different from control values. In another series of experiments, theophylline was fed to a group of rats to establish hypercalciuria. Three adenosine analogues N6-(L-2-phenylisopropyl)adenosine (R-PIA), N6-(D-2-phenylisopropyl)adenosine (S-PIA), and 5'-(N-ethylcarboxamido)adenosine (NECA) with different adenosine receptor specificities (A2,A1, and weakly A2, respectively) were administered to different groups of theophylline-fed and control rats, and their calcium excretions were measured. It was found that the order of efficacy of the analogues in reducing calcium excretion was NECA greater than R-PIA greater than S-PIA, which is consistent with the receptor being A2. A proportion of the methylxanthine-induced hypercalciuria may be due to adenosine antagonism.

The hypocalcemic effect of inorganic sulfate infusions.

Inorganic sulfate is a divalent anion that forms a soluble ion-pair complex with serum calcium, but the extent to which infusions of sulfate salts may depress the concentration of ionized calcium has never been quantitated. In a study of 9 patients who received sodium sulfate infusions as part of a standard diagnostic workup for their renal tubular acidosis, we observed a decrease in mean ionized calcium (adjusted to pH 7.40) from 1.15 +/- 0.01 to 1.04 +/- 0.02 mmol/l (p less than 0.01). The changes in ionized calcium were highly correlated with those in serum sulfate (r2 = 0.95; p less than 0.01). Quantitatively, an increase of 1 mmol/l in serum sulfate was associated with a decrease of 0.017 mmol/l in ionized calcium, a result that is in close agreement with in vitro data based on simple salt solutions. Diagnostic sulfate infusions should be used with caution in any patient predisposed to hypocalcemia.

Relationship between the sulfur content of total parenteral nutrition and sulfoester excretion in low-birthweight infants.

Inorganic sulfate is an end product of sulfur amino acid metabolism but it is also the cosubstrate for the biosynthesis of a wide array of complex sulfoesters. In vitro studies have shown that SO4 availability may be the primary determinant of sulfoconjugation rates for specific substrates but the relationship between S intake and sulfoester formation in vivo is not known. By substituting MgCl2 for MgSO4 in an amino acid infusate for parenteral nutrition, we were able to examine prospectively the effect of an altered SO4 load on S metabolism. In comparing 21 low-birthweight infants on the experimental MgC2 infusate with 14 subjects on the control MgSO4 infusate, we observed a 40% decrease in urinary excretion of free SO4 and a 31% decrease in excretion of total acid-labile sulfoesters. There was a significant correlation (r = 0.44; p less than 0.02) between total S intake and sulfoester excretion, suggesting that S intake influences sulfoconjugation in the low-birthweight infant requiring total parenteral nutrition.