The proliferation of normal human breast tissue implanted into athymic nude mice is stimulated by estrogen but not progesterone.

In order to resolve the question of which ovarian steroid stimulates normal human mammary epithelial cell proliferation, we have implanted pieces of normal human breast tissue subcutaneously into athymic nude mice. These mice were then treated with slow-release pellets containing estradiol (E2) or progesterone (P) such that serum levels of E2 and P were increased to those seen in normal women. The proliferative activity of the tissue implants was assessed by uptake of tritiated thymidine and steroid receptor expression was measured immunocytochemically. Insertion of a 2 mg E2 pellet 14 days after tissue implantation increased the thymidine labeling index (TLI) from a median of 0.4% (n = 34) to a median of 2.1% after 7 days (n = 43; P < 0.001 by Mann Whitney U test). In contrast, treatment with a P pellet (4 mg) had no effect upon the TLI whereas P (4 mg) in combination with E2 (2 mg) had no effect over and above that of E2 alone. There was a significant correlation between the increase in TLI and either the E2 content of the pellets (P < 0.001 by linear regression) or the serum E2 levels achieved (P < 0.001). Expression of the P receptor was increased 15- to 20-fold by E2 treatment. We conclude that E2 is sufficient to stimulate human breast epithelial cell proliferation at physiologically relevant concentrations and that P does not affect proliferation either alone or after E2 priming.

Migration of localizing wires used in guided biopsy of the breast.

Inadvertent retraction of a localizing wire into the breast occurred in three of a series of 158 localizations prior to biopsy for an impalpable mammographic abnormality. In each case retraction was followed by migration into the subcutaneous tissues and/or spontaneous extrusion. A wire inserted for localization prior to guided biopsy of the breast should be left long and secured externally to prevent retraction.

Response by women aged 65-79 to invitation for screening for breast cancer by mammography: a pilot study.

OBJECTIVE: To determine whether there is sufficient benefit to be gained by offering screening for breast cancer with mammography to women aged 65-79, who are not normally invited for screening. DESIGN: Pilot study of women eligible for screening but not for personal invitation. The results of this study were compared with the results of routinely screened younger women (aged 50-64) from the same general practice. SETTING: One group general practice in south Manchester. PATIENTS: The 631 women aged 65-79 on the practice list. A total of 42 (7%) were excluded by the general practitioner, and 22 (4%) invitation letters were returned by the post office. MAIN OUTCOME MEASURES: Response rates to invitation for screening assessed by three indices: crude population coverage ratio, crude invited population coverage ratio, and corrected invited population coverage ratio. RESULTS: 344 Patients aged 65-79 (61% of those invited, excluding those who could not be traced) were screened compared with 77% of women aged 50-64. The three response indices were higher for younger women than older: crude population coverage ratio = 66.5%, crude invited population coverage ratio = 69.3%, corrected invited population coverage ratio = 76.8% for women aged 50-64, compared with 54.5%, 58.4%, and 60.7% respectively for women aged 65-79. All four biopsies done in the older women gave positive results, giving a cancer detection rate of 11.6/1000 compared with 4.1/1000 among younger women. CONCLUSIONS: These results show that there is a potential for high attendance at routine screening by older women if they are invited in the same way as younger women. If these results are found elsewhere the costs and benefits of screening older women should be reassessed.

Gastrointestinal obstruction associated with Chlamydia trachomatis.

A patient is reported in whom adhesive obstruction of the small bowel was due to generalised peritonitis caused by Chlamydia trachomatis. It is concluded that any sexually active female with unexplained peritonitis or adhesive obstruction of the small bowel should be screened for chlamydial infection.

Biliary pharmacokinetics of ticarcillin and clavulanic acid.

The biliary excretion of ticarcillin and clavulanic acid was studied in 26 patients who required elective biliary surgery. In patients with normal hepatic function or unconjugated hyperbilirubinaemia the mean concentrations of ticarcillin in bile from common bile ducts and functioning gall bladders exceeded the mean concentration in plasma and bile from gall bladders with poor or absent function. Concentrations of ticarcillin in the walls of gall bladders were comparable regardless of function. In patients with obstructive jaundice, concentrations of ticarcillin in bile and the wall of gall bladders were lower than the concentrations in plasma. In all patients the mean concentrations of clavulanic acid in the biliary samples were invariably lower than the mean concentration in plasma.

The pharmacokinetics of cefotetan excretion in the unobstructed biliary tree.

Cefotetan excretion was studied in 17 patients undergoing biliary or pancreatic surgery. The antibiotic was detected in bile taken from the common bile duct within 15 min of a 1 g iv bolus and therapeutic plasma levels were found up to 10 h after administration. Even higher concentrations of cefotetan were measured in the bile from functioning gall bladders, despite the presence of gall stones. Concentrations of cefotetan in bile from the common bile ducts and functioning gall bladders were greater than the plasma concentrations at all times. These concentrations exceed the in-vitro minimum inhibitory concentrations (MIC) for most common biliary tract pathogens.

Breast screening and surgical problems.

The Edinburgh Breast Screening Clinic in its first year completed the initial screening examination of 3005 invited women, who were apparently in good health, aged between 40 and 60 years; 141 were referred for a surgical opinion; 70 women ultimately underwent biopsy and 9 proved to have carcinoma. The indications for biopsy are described together with methods of management of the various lesions.