Sex with animals (SWA): behavioral characteristics and possible association with penile cancer. A multicenter study.
BACKGROUND
Zoophilia has been known for a long time but, underreported in the medical literature, is likely a risk factor for human urological diseases.


OBJECTIVE
To investigate the behavioral characteristics of sex with animals (SWA) and its associations with penile cancer (PC) in a case-control study.


METHODS
A questionnaire about personal and sexual habits was completed in interviews of 118 PC patients and 374 controls (healthy men) recruited between 2009 and 2010 from 16 urology and oncology centers.


METHODS
SWA rates, geographic distribution, duration, frequency, animals involved, and behavioral habits were investigated and used to estimate the odds of SWA as a PC risk factor.


RESULTS
SWA was reported by 171 (34.8%) subjects, 44.9% of PC patients and 31.6% of controls (P < 0.008). The mean ages at first and last SWA episode were 13.5 years (standard deviation [SD] 4.4 years) and 17.1 years (SD 5.3 years), respectively. Subjects who reported SWA also reported more venereal diseases (P < 0.001) and sex with prostitutes (P < 0.001), and were more likely to have had more than 10 lifetime sexual partners (P < 0.001) than those who did not report SWA. SWA with a group of men was reported by 29.8% of subjects and SWA alone was reported by 70.2%. Several animals were used by 62% of subjects, and 38% always used the same animal. The frequency of SWA included single (14%), weekly or more (39.5%), and monthly episodes (15%). Univariate analysis identified phimosis, penile premalignancies, smoking, nonwhite race, sex with prostitutes, and SWA as PC risk factors. Phimosis, premalignant lesions, smoking, and SWA remained as risk factors in multivariate analysis. However, SWA did not impact the clinicopathological outcomes of PC.


CONCLUSIONS
SWA is a risk factor for PC and may be associated with venereal diseases. New studies are required in other populations to test other possible nosological links with SWA.
Urology Division of Pelvic Surgery Department, Hospital A C Camargo, São Paulo, SP, Brazil. steniozequi@uol.com.br
Stênio de Cássio
Sde C
Zequi
Gustavo Cardoso
GC
Guimarães
Francisco Paulo
FP
da Fonseca
Ubirajara
U
Ferreira
Wagner Eduardo
WE
de Matheus
Leonardo Oliveira
LO
Reis
Giuliano Amorim
GA
Aita
Sidney
S
Glina
Victor Silvestre Soares
VS
Fanni
Marjo Denisson Cardenuto
MD
Perez
Luiz Renato Montez
LR
Guidoni
Valdemar
V
Ortiz
Lucas
L
Nogueira
Luis Carlos
LC
de Almeida Rocha
Gustavo
G
Cuck
Walter Henriques
WH
da Costa
Ravendra Ryan
RR
Moniz
José Hipólito
JH
Dantas
Fernando Augusto
FA
Soares
Ademar
A
Lopes
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D001938:Brazil; D016022:Case-Control Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010262:Paraphilic Disorders / Q000150:complications*; D010412:Penile Neoplasms / Q000209:etiology*; D012307:Risk Factors; D060386:Sex Workers; D012747:Sexual Partners; D012749:Sexually Transmitted Diseases / Q000150:complications; D011795:Surveys and Questionnaires; D055815:Young Adult