Progestogen treatment options for early endometrial cancer.

OBJECTIVE: Premenopausal women with early endometrial cancer may wish to maintain their fertility, and for some patients non-surgical treatment options may be attractive. We have examined our own experience with such patients, as there are limited published data so far to support clear guidelines in this area. DESIGN: Retrospective analysis of a case series. SETTING: Case series from a specialist gynaecological oncology unit in a major tertiary referral hospital. SAMPLE: Sixteen patients receiving progestogen therapy for stage-1 endometrial cancer. METHODS: We reviewed our experience of all patients receiving progestogen therapy for stage-1 endometrial cancer, and we particularly examined their cancer-free outcome and fertility potential. MAIN OUTCOME MEASURES: Response to treatment, duration of response, and subsequent pregnancies. RESULTS: Of the 16 patients investigated, four received an oral progestogen, five received the levonorgestrel-releasing intrauterine system (Mirena), and seven received both forms of treatment. Ten patients (63%) responded to treatment, with a median time to response of 5.5 months. Six patients did not respond to treatment, but all were either early in treatment or opted for surgical management before the average time of response. No patient who responded had a later recurrence. The mean total follow-up time was 27 months (range 3-134 months), with no patient deaths. Three patients had successful pregnancies, with one patient having two children. CONCLUSIONS: This form of treatment appears to be a realistic treatment option in selected patients in the closely supervised environment of a specialist gynaecological oncology unit.

Use of sex-linked minisatellite fragments to investigate genetic differentiation and migration of North American populations of the peregrine falcon (Falco peregrinus).

The M13 repeat detects different levels of genetic variation in falcons. First, this minisatellite probe reveals typically highly variant restriction fragments that show no apparent unequal distribution between the sexes. Secondly, the M13 repeat detects sets of fragments that are only present in DNAs from female falcons. The level of polymorphism displayed by the sex-linked fragments is greatly reduced relative to most autosomal minisatellites. In addition, the size of these fragments (in kilobase pairs) is species-specific among Mauritius kestrels (Falco punctatus) and peregrines (Falco peregrinus). Variation observed at one o of the sex-linked fragments in peregrines has proven to be useful in distinguishing a subset of the tundrius subspecies of this endangered raptor. This correlation has enabled a genetic test to be used to examine the representation of tundrius peregrines during mass migration.

Organochlorine residues in Alaskan peregrines.

Organochlorine residue levels in eggs of Alaskan peregrines have remained essentially constant over the period 1969-73 despite decreased usage of these compounds in the United States and Canada. Studies on reproductive success in Great Britain and data on eggshell-thinning suggest that DDE residues above 20 ppm wet weight in peregrine eggs are associated with inability to maintain population levels. Residues in mainland Alaska are well above this critical figure and the reproductive rate is low. On the Colville River in northwestern Alaska, the last young falcons will fledge in 1975 and the remaining adult population will disappear by 1980 unless the present rate of reproductive failure is drastically and quickly reversed. In the Aleutians, however, levels range from 5 to 7 ppm and the reproductive rate is adequate to maintain the population.

DDE residues and eggshell changes in Alaskan falcons and hawks.

Eggshell thickness after exposure to DDT was reduced by 21.7 percent in Alaskan tundra peregrines, by 16.8 percent in taiga peregrines, by 7.5 percent in Aleutian peregrines, by 3.3 percent in rough-legged hawks, and not at all in gyrfalcons. Tundra peregrine eggs contain an average of 889 parts of DDE per million (lipid basis); taiga peregrine eggs contain 673 parts per million; Aleutian peregrine eggs contain 167 parts per million; rough-legged hawk eggs contain 22.5 parts per million; and gyrfalcon eggs contain 3.88 parts per million. These changes in eggshell thickness and the pesticide residues reflect different degrees of exposure to contamination. There is a highly significant negative correlation between shell thickness and DDE content in peregrine eggs. Tundra and taiga peregrines have fledged progressively fewer young each year since 1966.