Background. Cervical adenocarcinoma in situ is often diagnosed in younger women who may wish to preserve the potential for fertility. Given that the rate of recurrent adenocarcinoma in situ is relatively low and the risk of invasive adenocarcinoma is extremely rare, conservative management in this population after a cone biopsy demonstrates negative margins has been accepted as an appropriate management strategy. This case challenges the concept of conservative management of cervical adenocarcinoma in situ. Case. A 42- year- old G2P2002 with previously normal annual cervical cytology had a Pap smear demonstrating atypical glandular cells of uncertain significance. A 1.5- cm lesion was noted at the endocervix, and a punch biopsy revealed adenocarcinoma in situ. A large cold knife cone biopsy confirmed cervical adenocarcinoma in situ with negative margins. Definitive therapy for in situ disease with an extrafascial hysterectomy was performed 12 days after conization, and demonstrated stage IB1 cervical adenocarcinoma. A radical parametrectomy, radical upper vaginectomy, and pelvic lymphadenectomy were without persistent disease. Conclusion. Conservative management of cervical adenocarcinoma in situ after a cone biopsy with negative margins does not exclude the possibility of concurrent invasive cervical adenocarcinoma. This case challenges the current balance between risk and benefit associated with the conservative management of cervical adenocarcinoma in situ. Background. Cervical adenocarcinoma in situ is often diagnosed in younger women who may wish to preserve the potential for fertility. Given that the rate of recurrent adenocarcinoma in situ is relatively low and the risk of invasive adenocarcinoma is extremely rare, conservative management in this population after a cone biopsyposit negative margins has been accepted as an appropriate management strategy. This case challenges the concept of conservative management of cervical adenocarcinoma in situ. Case. A 42- year- old G2P2002 with previously normal annual cervical cytology had a Pap smear demonstrating atypical A 1.5-cm lesion was noted at the endocervix, and a punch biopsy revealed adenocarcinoma in situ. A large cold knife cone biopsy confirmed cervical adenocarcinoma in situ with negative margins. Definitive therapy for in situ disease with an extrafascial hysterectomy was performed 12 days after conization, and demonstrated sta ge IB1 cervical adenocarcinoma. A radical parametrectomy, radical upper vaginectomy, and pelvic lymphadenectomy were without persistent disease. Conclusion. Conservative management of cervical adenocarcinoma in situ after a cone biopsy with negative margins does not exclude the possibility of concurrent invasive cervical adenocarcinoma. This case challenges the current balance between risk and benefit associated with the conservative management of cervical adenocarcinoma in situ.