Recurrences Of Non Metastatic Merkel Cell Carcinoma After Surgery And Radiotherapy Occur More Frequently Outside The Irradiated Fields

Purpose/Objective(s)To analyze retrospectively results of surgery followed by external beam radiotherapy (EBRT) for non metastatic Merkel cell carcinoma. To analyze recurrence according to the irradiated fields (IF).Materials/MethodsThirty-two patients (pts) with a median age of 77 years (range, 37-88) were treated for Merkel cell carcinoma (MCC) between November 1983 and November 2007 in 2 institutions. There were 10 men and 22 women. Second cancer before Merkel cell carcinoma was observed in 13 pts. Tumors stage (according to Yiengpruksawan classification) were: stage I (primary lesion only) (20 pts) and stage II (primary lesion with lymph node) (12 pts). By TNM staging, pts were T1 (54%), T2 (39%) and T3 (7%). Tumor was located in: head and neck (15 pts), limbs (13 pts) and trunk (4 pts). Treatment consisted of surgery of the primary (24 pts) and lymphadenectomy (7 pts). Surgery was microscopically complete in 54% of pts, with positive margins in 38% of pts and macroscopically incomplete in 8% of pts. EBRT was given in the tumor bed (all pts) to a median total dose of 57 Gy (range, 40-72). The median PTV margin around the tumor bed was 30 mm (range, 15-50). Lymph node areas were irradiated in 24 pts (12 stage I pts and 12 stage II pts), to a median total dose of 50 Gy (range, 6-70).ResultsMedian follow-up was 19 months (range, 2-171). The 5-year risk of local recurrence, lymph node recurrence, metastases or any recurrence rates were: 33% (95% CI: 13-53%), 45% (95% CI: 19-71%), 54% (95% CI: 24-84%) and 73% (95% CI: 53-93%), respectively. Local recurrences were observed in 9 pts: 3 pts presenting recurrence inside the IV, 4 pts outside the IV and 2 pts in the border of the IV. Lymph node recurrences were observed in 9 pts: 3 pts presenting recurrence inside the IV and 6 outside the IV. The 5-year cancer specific survival and overall survival (OS) rates were: 36% (95% CI: 12-60%). In univariate analysis, the only predictive factors on OS were: T stage (p = 0.05), quality of resection (p < 0.01) and diameter of the tumor (RR = 1.04 (95% CI: 1.01-1.07), p = 0.007).ConclusionsMCC is an aggressive skin cancer with high risk of both local and lymph node recurrences and metastases, despite local treatment combining surgery and EBRT. Two-third of the recurrence occurred in the border or outside the irradiated fields, suggesting enlarging the irradiation volume if possible, rather than increasing total dose of irradiation. Purpose/Objective(s)To analyze retrospectively results of surgery followed by external beam radiotherapy (EBRT) for non metastatic Merkel cell carcinoma. To analyze recurrence according to the irradiated fields (IF). To analyze retrospectively results of surgery followed by external beam radiotherapy (EBRT) for non metastatic Merkel cell carcinoma. To analyze recurrence according to the irradiated fields (IF). Materials/MethodsThirty-two patients (pts) with a median age of 77 years (range, 37-88) were treated for Merkel cell carcinoma (MCC) between November 1983 and November 2007 in 2 institutions. There were 10 men and 22 women. Second cancer before Merkel cell carcinoma was observed in 13 pts. Tumors stage (according to Yiengpruksawan classification) were: stage I (primary lesion only) (20 pts) and stage II (primary lesion with lymph node) (12 pts). By TNM staging, pts were T1 (54%), T2 (39%) and T3 (7%). Tumor was located in: head and neck (15 pts), limbs (13 pts) and trunk (4 pts). Treatment consisted of surgery of the primary (24 pts) and lymphadenectomy (7 pts). Surgery was microscopically complete in 54% of pts, with positive margins in 38% of pts and macroscopically incomplete in 8% of pts. EBRT was given in the tumor bed (all pts) to a median total dose of 57 Gy (range, 40-72). The median PTV margin around the tumor bed was 30 mm (range, 15-50). Lymph node areas were irradiated in 24 pts (12 stage I pts and 12 stage II pts), to a median total dose of 50 Gy (range, 6-70). Thirty-two patients (pts) with a median age of 77 years (range, 37-88) were treated for Merkel cell carcinoma (MCC) between November 1983 and November 2007 in 2 institutions. There were 10 men and 22 women. Second cancer before Merkel cell carcinoma was observed in 13 pts. Tumors stage (according to Yiengpruksawan classification) were: stage I (primary lesion only) (20 pts) and stage II (primary lesion with lymph node) (12 pts). By TNM staging, pts were T1 (54%), T2 (39%) and T3 (7%). Tumor was located in: head and neck (15 pts), limbs (13 pts) and trunk (4 pts). Treatment consisted of surgery of the primary (24 pts) and lymphadenectomy (7 pts). Surgery was microscopically complete in 54% of pts, with positive margins in 38% of pts and macroscopically incomplete in 8% of pts. EBRT was given in the tumor bed (all pts) to a median total dose of 57 Gy (range, 40-72). The median PTV margin around the tumor bed was 30 mm (range, 15-50). Lymph node areas were irradiated in 24 pts (12 stage I pts and 12 stage II pts), to a median total dose of 50 Gy (range, 6-70). ResultsMedian follow-up was 19 months (range, 2-171). The 5-year risk of local recurrence, lymph node recurrence, metastases or any recurrence rates were: 33% (95% CI: 13-53%), 45% (95% CI: 19-71%), 54% (95% CI: 24-84%) and 73% (95% CI: 53-93%), respectively. Local recurrences were observed in 9 pts: 3 pts presenting recurrence inside the IV, 4 pts outside the IV and 2 pts in the border of the IV. Lymph node recurrences were observed in 9 pts: 3 pts presenting recurrence inside the IV and 6 outside the IV. The 5-year cancer specific survival and overall survival (OS) rates were: 36% (95% CI: 12-60%). In univariate analysis, the only predictive factors on OS were: T stage (p = 0.05), quality of resection (p < 0.01) and diameter of the tumor (RR = 1.04 (95% CI: 1.01-1.07), p = 0.007). Median follow-up was 19 months (range, 2-171). The 5-year risk of local recurrence, lymph node recurrence, metastases or any recurrence rates were: 33% (95% CI: 13-53%), 45% (95% CI: 19-71%), 54% (95% CI: 24-84%) and 73% (95% CI: 53-93%), respectively. Local recurrences were observed in 9 pts: 3 pts presenting recurrence inside the IV, 4 pts outside the IV and 2 pts in the border of the IV. Lymph node recurrences were observed in 9 pts: 3 pts presenting recurrence inside the IV and 6 outside the IV. The 5-year cancer specific survival and overall survival (OS) rates were: 36% (95% CI: 12-60%). In univariate analysis, the only predictive factors on OS were: T stage (p = 0.05), quality of resection (p < 0.01) and diameter of the tumor (RR = 1.04 (95% CI: 1.01-1.07), p = 0.007). ConclusionsMCC is an aggressive skin cancer with high risk of both local and lymph node recurrences and metastases, despite local treatment combining surgery and EBRT. Two-third of the recurrence occurred in the border or outside the irradiated fields, suggesting enlarging the irradiation volume if possible, rather than increasing total dose of irradiation. MCC is an aggressive skin cancer with high risk of both local and lymph node recurrences and metastases, despite local treatment combining surgery and EBRT. Two-third of the recurrence occurred in the border or outside the irradiated fields, suggesting enlarging the irradiation volume if possible, rather than increasing total dose of irradiation.