Urban-rural differences of gynaecological malignancies in Egypt (1999-2002).
OBJECTIVE
In previous studies, we have shown a three to four times higher urban incidence of breast cancer and estrogen receptor-positive breast cancers in the Gharbiah Province of Egypt. We investigated the urban-rural incidence differences of gynaecologic malignancies (uterine, ovarian and cervical cancers) to explore if they show the same trend that we found for breast cancer.


METHODS
Cancer registry-based incidence comparison.


METHODS
Gharbiah population-based cancer registry (GPCR), Tanta, Egypt.


METHODS
All patients with uterine, ovarian and cervical cancer in GPCR from 1999 to 2002.


METHODS
We calculated uterine, ovarian and cervical cancer incidence from 1999 to 2002. For each of the three cancers, we calculated the overall and age-specific rates for the province as a whole, and by urban-rural status, as well as for the eight districts of the province.


RESULTS
Incidence of all three cancer sites was higher in urban than in rural areas. Uterine cancer showed the highest urban-rural incidence rate ratio (IRR = 6.07, 95% CI = 4.17, 8.85). Uterine cancer also showed the highest urban incidence in the oldest age group (70+ age category, IRR = 14.39, 95% CI = 4.24, 48.87) and in developed districts (Tanta, IRR = 4.14, 95% CI = 0.41, 42.04). Incidence rates by groups of cancer sites showed an increasing gradient of urban incidence for cancers related to hormonal aetiology, mainly of the breast and uterus (IRR = 4.96, 95% CI = 2.86, 8.61).


CONCLUSIONS
The higher urban incidence of uterine cancer, coupled with our previous findings of higher incidence of breast cancer and estrogen receptor positive breast cancer in urban areas in this region, may be suggestive of possible higher exposure to environmental estrogenic compounds, such as xenoestrogens, in urban areas.
Dey
S
S
Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI 48109, USA.
Hablas
A
A
Seifeldin
I A
IA
Ismail
K
K
Ramadan
M
M
El-Hamzawy
H
H
Wilson
M L
ML
Banerjee
M
M
Boffetta
P
P
Harford
J
J
Merajver
S D
SD
Soliman
A S
AS
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D002648:Child; D002675:Child, Preschool; D004534:Egypt / Q000453:epidemiology; D005260:Female; D005833:Genital Neoplasms, Female / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008875:Middle Aged; D010051:Ovarian Neoplasms / Q000453:epidemiology; D012042:Registries; D012423:Rural Health / Q000706:statistics & numerical data*; D014504:Urban Health / Q000706:statistics & numerical data*; D002583:Uterine Cervical Neoplasms / Q000453:epidemiology; D014594:Uterine Neoplasms / Q000453:epidemiology; D055815:Young Adult