The importance of postoperative radiation therapy in the treatment of Merkel cell carcinoma.
OBJECTIVE
To determine the role of postoperative radiation therapy in the treatment of Merkel cell carcinoma (MCC).


METHODS
Eighty patients with MCC of the skin were treated with curative intent at the Queensland Radium Institute between 1981 and 1991. Fifty-one patients (63.7%) were referred after initial biopsy for further treatment and 29 patients (36.3%) were referred with locally recurrent disease following primary surgery elsewhere. Thirteen patients (16.3%) presented with nodal disease without a clinically definable primary skin lesion.


RESULTS
Of the 80 patients, 38 had undergone surgery (S) alone, 34 surgery plus radiotherapy (S + RT), 7 RT after incomplete S, and 1 patient had chemotherapy (CT) plus RT. Overall survival at 36 months for all patients was 68%. All of the 38 patients treated with S alone relapsed. The median time to recurrence was 5.5 months. Ten of the 34 patients treated with S + RT relapsed. The median time to recurrence was 16.5 months. Of the 80 patients, 55 have relapsed after primary treatment, 25 have developed systemic metastases, and 26 patients have died as a direct result of MCC.


CONCLUSIONS
Our large series confirms earlier reports from this Institute and highlights the importance of S + RT over S alone in preventing local recurrence of this highly malignant skin cancer.
Meeuwissen
J A
JA
Queensland Radium Institute, Royal Brisbane Hospital, Australia.
Bourne
R G
RG
Kearsley
J H
JH
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015266:Carcinoma, Merkel Cell / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery*; D003131:Combined Modality Therapy; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D012008:Recurrence; D012878:Skin Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery*; D015996:Survival Rate; D013997:Time Factors