Long-term follow-up of axillary node-positive breast cancer patients receiving adjuvant systemic therapy alone: patterns of recurrence.

PURPOSE: Prognostic factors for locoregional failure have been poorly documented. The purpose of this retrospective review is to examine the patterns of failure of 320 patients with Stage II or III axillary node-positive breast cancer who received adjuvant chemotherapy without locoregional radiation.

METHODS AND MATERIALS: The records of 735 patients who were referred to the London Regional Cancer Centre between 1980 and 1989 with a diagnosis of Stage II or III breast cancer were reviewed. Three hundred and twenty patients were identified who underwent segmental mastectomy with axillary dissection or modified radical mastectomy and adjuvant chemotherapy without adjuvant locoregional radiation. Seventy-one percent of these patients had undergone a modified radical mastectomy, 40% had T1 tumors, 49% T2, and 11% T3. Resection margins were positive in 13 patients. The median number of axillary nodes removed was 11. Fifty-four percent had one to three positive axillary nodes, 27% had four to seven positive nodes, and 19% had in excess of seven positive nodes.

RESULTS: Median follow-up for the 320 patients was 77 months. One hundred and fourteen patients developed a locoregional recurrence as the site of first relapse (31 in the intact breast, 29 on the chest wall, 21 in the axilla, 22 in the supraclavicular fossa, 1 in the internal mammary chain, and 10 in multiple sites). Thirty-three percent of segmental mastectomy patients and 13% of modified radical mastectomy patients developed local recurrence. Seven percent of patients recurred in axillary or supraclavicular nodes each. Factors with regard to locoregional recurrence which on univariate analysis were significant included type of mastectomy (i.e., segmental vs. modified radical), size of primary tumor, positive resection margins, and percentage of ideal chemotherapy dose intensity (< 66% vs. > or = 66%). After multivariate analysis, only type of mastectomy, size of primary tumor, and percentage of ideal chemotherapy dose intensity retained significance. The number of positive axillary nodes was not a significant factor. Number of positive axillary nodes plus the above four clinical factors were analyzed in terms of regional recurrence specifically. By univariate and multivariate analysis, only size of primary tumor retained significance. Again, the number of positive axillary nodes was not a relevant factor.

CONCLUSION: Patients receiving adjuvant chemotherapy who are at high risk of locoregional recurrence include those who undergo segmental mastectomy and those with larger tumors (> 5 cm in diameter). Breast or chest wall radiation is recommended for these groups. Supraclavicular radiation is recommended for patients with tumors larger than 5 cm in diameter. Axillary recurrences were relatively infrequent in patients who had undergone an adequate Level I and II axillary dissection, and therefore, axillary radiation was not recommended.