Using data from the Surveillance, Epidemiology, and End Results (SEER) program, Dawood et al compared the survival of women with stage III inflammatory (IBC) and noninflammatory (non-IBC) breast cancer in the era of preoperative taxane therapy.1 SEER does not code for chemotherapy, and therefore the authors assumed that patients with inoperable stage III disease who had completed surgery and radiotherapy would have received preoperative chemotherapy. This selection method has several drawbacks. Most significantly, it includes non-IBC patients who were treated surgically based on clinical staging but later reclassified as IIIC upon pathologic lymph node (LN) assessment (eg, pN3a: metastasis in ≥ 10 LNs). In addition, patients who receive preoperative chemotherapy but fail to achieve a clinical response are excluded (up to 20% of IBC cases), whereas nonresponders who subsequently achieve downstaging through second-line chemotherapy or preoperative radiotherapy may still be selected.
The large discrepancy reported in stage IIIC cases between patients with non-IBC (70%) and those with IBC (20%) may result in part from the pathologic restaging of patients with non-IBC who are treated surgically. In addition, whereas meticulous LN assessment is crucial in determining the operability of patients with non-IBC, staging of LNs using fine-needle aspiration cytology or core needle biopsies in patients with IBC is inaccurate and appears to have little or no impact on the therapeutic decision-making. Moreover, prechemotherapy sentinel LN biopsy of clinically negative LNs (recommended in 2004) is contraindicated in patients with IBC.2 Inaccurate control for confounders such as LN positivity and human epidermal growth factor receptor 2 (HER2) status (coded in 2004) results in an imprecise multivariate model and obscures the relation between treatment and outcome.
This is the first SEER study to use the T4d code and the Collaborative Staging System. The authors should provide pathological correlation in the form of extent of disease (EOD-E 70, EOD-S 998) and International Classification of Diseases for Oncology Second Edition (ICD-O-2) morphology code 8530/3 as suggested by Hance et al.3 Pathology is an important confirmatory component in the diagnosis, and correlation will allow for validation of the new staging codes as well as longitudinal comparison with similar SEER studies.