Assessment of skin response in T4b breast carcinoma patients post-neoadjuvant chemotherapy

Breast cancer patients with skin ulcerations, satellite nodules or Peau d'orange at presentation are classified with stage 4 breast cancer (T4b). Neoadjuvant chemotherapy (NACT), followed by mastectomy, is the commonly accepted treatment in such patients for fear of adverse outcomes with breast conservation surgery (BCS) and uncertainty over sparing initially involved skin irrespective of the response to chemotherapy. Identifying patients with skin resolution post-NACT can help surgeons in decision-making.

To assess skin response in T4b breast cancer patients post-NACT and find the correlation between various clinical and pathological factors associated with no skin involvement on final histology.

Records of breast cancer patients managed at the Tata Medical Center, Kolkata, with NACT for T4b breast carcinoma patients who underwent mastectomy were reviewed between January 2014 and December 2018. Final histology was checked for dermal involvement with the tumour. The Mann-Whitney U test was used for continuous variables for descriptive data, and Pearson's chi-squared and Fischer's exact tests were applied for categorical data. p-value < 0.05 was taken as significant.

A total of 285 records mentioning skin involvement were reviewed, out of which 111 patients fulfilled the AJCC criterion. The median age at diagnosis of T4b breast cancer was 50 years. The median clinical size pre-chemotherapy was 7 cm. Residual median tumour size on final histology was reported as 1 cm. 78/111 patients showed a post-NACT response of 50% or more, and 43/111 showed a response of more than 90%. 57 (51.4%) patients showed skin involvement on final histopathology, while 54 (48.6%) patients did not.ER negative tumours were more likely to show no dermal involvement (p = 0.006). Residual tumour size of less than 1 cm on final histology (p < 0.05) and nodal stage were significant predictors of dermal response.

Approximately half of the T4b breast cancer patients showed resolution of dermal skin involvement post-NACT. ER negative and those with residual tumour size less than 1 cm post-NACT are more likely to show dermal resolution. This can help surgeons plan a BCS or skin sparing mastectomy for such patients who usually end up having a mastectomy.