Giant condyloma acuminata, first described by Buschke and Löwenstein in 1925 as a penile lesion, is extremely rare in the anorectal region. The cauliflower-like tumor behaves clinically in a malignant fashion, although it shows no histomorphological criteria of malignancy. Up to the time of writing only 33 cases of anorectal origin, 42% with malignant transformation, have been published. The authors report 2 more cases of squamous-cell carcinoma in giant anorectal condylomata acuminata. Buschke-Löwenstein tumor is an intermediate entity between "ordinary" condyloma acuminata and squamous-cell carcinoma. Benign condyloma acuminata is caused by human papillomavirus 6 or 11. Carcinogenic cofactors promote the transition to giant, locally destructive condyloma acuminata and subsequent malignant transformation. Cure can only be achieved by early and radical excision. Formation of multiple fistulas and destruction of the sphincter may necessitate abdomino-perineal resection. Adjuvant radiation therapy should only be considered to render a tumor operable, as radiation may act as a cocarcinogenic effect and lead to a less differentiated and more aggressive cancer. The small number of cases reported and the variety of treatment regimens applied, however, do not allow the formulation of definitive therapeutic guidelines.