Abnormal cervical cytology after allogeneic bone marrow transplantation

Allogeneic bone marrow transplantation (BMT) is a procedure mostly used for high-risk hematologic malignances. In women, follow-up protocols after BMT include gynecologic checkups with Papanicolaou (Pap) smears. We evaluated 117 Pap smears in 54 women who underwent allogeneic BMT and correlated the smear morphology with the BMT-related medical treatment. Abnormal Pap smears after BMT were found in 13 (24.1%) women. Four (7.4%) women had at least one smear with atypical squamous cells of unknown significance, six (11.1%) had a low-grade squamous intraepithelial lesion, and three (5.6%) had atypical squamous cells/high-grade lesion cannot be excluded (ASC-H). The three patients with ASC-H showed high-grade atypia mimicking cancer but had a negative follow-up. Nine women, including the three with ASC-H, had undergone a conditioning therapy for BMT that included busulfan. No association between other drugs and therapy-related atypia was found. Pap smears after BMT show a high incidence of dysplastic lesions. Moreover, conditioning including busulfan is often associated with therapy-related cytologic atypia, which may lead to unnecessary colposcopies and biopsies. Knowledge of the patient's history and a careful evaluation of the smears are mandatory in these cases.