No abstract

Objective: To investigate the role of post-mastectomy radiotherapy in breast carcinoma patients with a tumor size of 5 cm or smaller (T1-2) and 1 -3 axillary lymph node(s) metastasis (N1). Methods: We retrospectively reviewed the file records of 575 patients receiving radiotherapy (452 patients) and not receiving radiotherapy (123 patients). Results: In the whole series, locoregional recurrence-free survival was significantly better in patients receiving radiotherapy compared with patients not receiving radiotherapy (P , 0.001); in the multivariate Cox analysis, radiotherapy had an independent prognostic value (P , 0.001). In patients with a tumor size of 2 cm or less (T1), locoregional recurrence-free survival was significantly better in patients receiving radiotherapy compared with those not receiving radiotherapy (P ¼ 0.016). In the patient subgroup with a T1 tumor and a lymph node ratio (the ratio of the number of metastatic lymph nodes to the number of removed lymph nodes) of 0.25 or less, there was no significant difference between the patients receiving and not receiving radiotherapy in terms of locoregional recurrence-free survival (P ¼ 0.071). In patients with a tumor size of 2.1 -5 cm (T2), locoregional recurrence-free survival was significantly better for patients who received radiotherapy compared with those who did not (P ¼ 0.001). In patients with a T2 tumor and a lymph node ratio of 0.08, there was no significant difference in locoregional recurrence-free survival between the patients receiving and not receiving radiotherapy (P ¼ 0.645). Conclusions: Post-mastectomy radiotherapy is beneficial in reducing the locoregional recurrence risk in T1N1 breast carcinoma patients with a lymph node ratio of .0.25 and in T2N1 breast carcinoma patients with a lymph node ratio of .0.08. In patients with a lymph node ratio equal to or less than these ratios, post-mastectomy radiotherapy could be omitted to avoid radiotherapy-related risks.

Patients with T1,2,3N3M0 disease can be divided into prognostically different subgroups according to the number of metastatic lymph nodes in the axilla and the nodal ratio; in this way, different patient subgroups may be offered different treatment strategies.

According to tumor-node-metastasis classification, tumor size should be based only on the largest tumor for multifocal and multicentric (MFMC) carcinomas. We estimated tumor size of MFMC carcinoma using either largest dimension of the largest tumor (dominant tumor size) or sum of the largest dimension of all tumors (aggregate tumor size), and compared the risk of axillary lymph node metastasis and prognosis between MFMC and unifocal carcinoma. We retrospectively reviewed the file records of 3,616 patients with MFMC (258 patients, 7.1%) and unifocal (3,358 patients) carcinoma. In T1 and T2 tumor subgroups, using dominant (p = 0.001 and p < 0.001) and aggregate (p = 0.017 and p = 0.004) tumor size axilla-positivity ratio was significantly higher in MFMC carcinoma compared with unifocal carcinoma. In stage I and II disease classified according to either dominant or aggregate tumor size, there was no significant survival difference between MFMC and unifocal carcinoma patients. In patients with stage III disease by dominant and aggregate tumor size disease-free survival was significantly worse in MFMC carcinoma compared with unifocal carcinoma (p = 0.036 and p = 0.041); multifocality and multicentricity had no independent prognostic significance (p = 0.074 and p = 0.079). The risk of axillary metastasis in MFMC carcinoma was higher than unifocal carcinoma, regardless of the method employed for tumor size estimation. MFMC carcinoma staged according to either dominant or aggregate tumor size had similar survival with unifocal carcinoma. We recommend using the largest dimension of the largest tumor in estimation of tumor size for MFMC carcinoma.

Resection of colorectal tumor in primary CRC patients with non-resectable distant metastasis gives significant survival advantage without increasing postoperative mortality compared with non-resection.