UCSF

Objective

To characterize population-level surgical treatment patterns for cervical carcinoma in situ (CIS) reported to the Michigan Cancer Surveillance Program (MCSP), and to inform data collection strategies.

Methods

All cases of cervical carcinoma in situ (CIS) (including cervical intraepithelial neoplasia grade 3 and adenocarcinoma in situ [AIS]) reported to the MCSP during 1998-2003 were identified. First course of treatment (ablative procedure, cone biopsy, loop electrosurgical excisional procedure [LEEP], hysterectomy, unspecified surgical treatment, no surgical treatment, unknown if surgically treated) was described by histology, race, and age at diagnosis.

Results

Of 17,022 cases of cervical CIS, 82.8 percent were squamous CIS, 3 percent AIS/adenosquamous CIS, and 14.2 percent unspecified/other CIS. Over half (54.7 percent) of cases were diagnosed in women under age 30. Excisional treatments (LEEP, 32.3 percent and cone biopsy, 17.3 percent) were most common, though substantial proportions had no reported treatment (17.8 percent) or unknown treatment (21.1 percent). Less common were hysterectomy (7.2 percent) and ablative procedures (2.6 percent). LEEP was the most common treatment for squamous cases, while hysterectomy was the most treatment for AIS/adenosquamous CIS cases. Across histologic types, a sizeable proportion of women diagnosed ≤30 years of age underwent excision, either LEEP (20 percent-38.7 percent) or cone biopsy (13.7 percent-44 percent).

Conclusion

Despite evidence suggesting it may be safer and equally effective as excision, ablation was rarely used for treating cervical squamous CIS. These population-based data indicate some notable differences in treatment by histology and age at diagnosis, with observed patterns appearing consistent with consensus guidelines in place at the time of study, but favoring more aggressive procedures. Future data collection strategies may need to validate treatment information, including the large proportion of no or unknown treatment.