Abstract:

Objective

To investigate clinical characteristics and surgical options for different pathological types of chronic mastitis.

Methods

The study included 259 hospitalized patients with chronic mastitis in Department of Breast Surgery, Southwest Hospital, from February 2003 to November 2015.According to pathological findings, they were divided into plasma cell mastitis (PCM) group (n=111) and granulomatous mastitis (GM) group (n=148). Clinical data were compared between two groups, including clinical features and surgical options, and the follow-up data were analyzed to compare the recurrence.Measurement data including age, hospital stay were processed using independent sample t test and rank sum test, count data were processed using chi-square test and Kaplan-Meier survival curve was used to analyze the recurrence.

Results

The average onset age was (30.1 ± 6.9) years in PCM group, significantly lower than(32.7 ± 7.8) years in GM group (t=2.81, P=0.005). The distribution of onset age showed a statistical difference between groups (χ²=10.36, P=0.006). Most of chronic mastitis patients were 26 to 35 years old.The patients with single mass as the main clinical manifestations accounted for 72.3% in GM group and 52.3% in PCM group respectively. The main clinical manifestations between two groups were significantly different (χ²=13.68, P=0.003). There were 105 patients (70.9%,105/148) with the distance from lesion to nipple≤2 cm in GM group, 93 (83.8%, 93/111) in PCM group, and the difference was statistically significant (χ²=5.80, P=0.016). There were 101 patients without inverted nipple (68.2%,101/148) in GM group,54 (48.7%,54/111) in PCM group, suggesting a statistical difference (χ²=10.13, P=0.001).More PCM patients had more previous use of antibiotic and hormonal drugs than GM patients did (χ²=4.87,P=0.027). There was no significant difference between two groups in lesion location and operation frequency distribution (χ²=7.32, P=0.198; χ² =3.95, P=0.139). In all patients, 38 cases received incision and drainage, 186 received mass or local resection and 35 received mastectomy, and the recurrence rate was 78.9% (30/38), 55.4% (103/186) and 0 respectively, indicating a significant difference in patients receiving different operations (χ² =49.74, P ＜0.001). The recurrence rate in patients with drainage was significantly higher than that in patients with mass or local resection(χ²=7.27,P=0.007).The interval from operation to recurrence was 66.0 d in patients receiving incision and drainage, 92.0 d in patients receiving mass or local resection, indicating a significant difference (χ²=4.90, P=0.030).

Conclusions

PCM has lower onset age than GM, while both have single mass as main clinical manifestation. PCM lesions are mostly located within 2 cm from the nipple. The mass or local resection is superior to drainage in chronic mastitis.

Key words: Mastitis, Drainage, Mastectomy, Recurrence