Adjuvant therapy of cutaneous malignant melanoma: a critical review

Adjuvant therapy for cutaneous malignant melanoma

We discuss the current status of adjuvant therapy for melanoma by first reviewing the rationale and goals of adjuvant therapy and then analyzing the results of published randomized trials. We pay particular attention to adjuvant interferon trials that raise many challenging issues in the management of patients with melanoma at high risk of recurrence. Past adjuvant trials have used immunotherapeutic approaches, chemotherapy, radiation therapy, as well as hormonal and retinoid therapy. We also summarize ongoing adjuvant trials.

Management of stage I malignant melanoma

BACKGROUND

Because of the rising incidence of melanoma, dermatologists are increasingly responsible for diagnosing and managing patients with this cutaneous malignancy. Fortunately, with the increased awareness and emphasis on early detection, most patients will present with tumors that have not yet spread beyond their primary focus in the skin (ie, Stage I). Dermatologists must, therefore, be fully versed in the diagnosis and management of Stage I melanoma.

OBJECTIVE

This review article focuses on the most important issues related to the diagnosis and management of Stage I melanoma. An emphasis will be placed on surgical management.

RESULTS

The mainstay of therapy for most patients with Stage I melanoma is surgery. The important principles of diagnostic biopsy and surgical excision will be discussed. There are several additional modalities that may be useful as adjuvants to surgical therapy or as primary therapy in situations when surgery is not feasible. Those include elective lymph node dissection, hyperthermic isolation limb perfusion, radiotherapy, cryotherapy, chemotherapy, and immunotherapy. These will all be reviewed.

CONCLUSIONS

With a thorough understanding of the important principles and controversies related to the management of Stage I melanoma, dermatologists can effectively manage the growing number of patients with this malignancy.

Radiation therapy for nodal disease in malignant melanoma

Radiation therapy has been widely used for palliative management of inoperable metastatic malignant melanoma. For patients with nodal disease, response rates of approximately 70% have been reported. There are limited data concerning the role of adjuvant irradiation following therapeutic lymph node dissection. In this review, 57 patients with isolated resectable and nonresectable nodal disease have been treated with radiation. The overall response rate is 84% for bulky disease. Large fractions are beneficial. The median disease-free survivals were 11 months after adjuvant treatment and 7 months for those with inoperable disease. The median overall survivals were 20 months and 18 months, respectively. Local control in long-term survivors was excellent. Sixty-five percent of patients developed distant metastases. There is a need for additional studies with the use of adjuvant radiation therapy following lymph node dissection.

Stage II melanoma in the west of Scotland, 1976-1985: prognostic factors for survival

The outcome of 142 patients undergoing therapeutic lymphadenectomy for clinical stage II malignant melanoma was retrospectively assessed. 5 year survival was 26%, and survival was not altered in the 25 patients who received two courses of adjuvant combination chemotherapy after lymphadenectomy. On univariate analysis, the most significant determinants of survival were the number of malignant nodes removed at lymphadenectomy (P = 0.00004), the age of the patient (P = 0.009) and the disease-free interval between primary and stage II disease (P = 0.01). The following features were not significantly related to survival: sex, site, histogenetic type of primary tumour, tumour thickness and level of invasion. The number of malignant lymph-nodes was confirmed on multivariate analysis as the single most useful and significant predictor of survival, with the patient's age providing an additional significant contribution. In future adjuvant trials in stage II melanoma after therapeutic lymphadenectomy, patients should be stratified for both age and number of malignant nodes.

Survival of patients with metastases from uveal melanoma

The authors evaluated a series of 145 consecutive patients with metastases from uveal melanoma, after proton beam irradiation, to assess the effect of early diagnosis and treatment for metastases on survival. Metastases were diagnosed between 7 weeks and 8.3 years (median, 2.4 years) after proton beam irradiation. Most patients (n = 94) were symptomatic before diagnosis; the remainder were first detected during screening examination. Liver involvement was documented in nearly all patients (n = 136). The majority of patients had died from metastases by the close of the study (n = 137). Significantly longer survival occurred among patients diagnosed during screening examination (P = 0.004) and among young patients (P = 0.03). The majority of patients received some form of treatment for metastases (69%). Median survival was 2.0 months for patients receiving no treatment compared with 5.2 months for those receiving treatment for metastases (P = .0001). However, the overall 1-year survival rate was poor (13%). Prophylactic adjuvant therapy could be explored as a means to increase disease-free survival in patients with uveal melanoma.

Malignant melanoma in children: its management and prognosis

Malignant melanoma is rare in children, representing 1% to 3% of all pediatric malignancies. Thirty-three children with malignant melanoma were treated at St Jude Children's Research Hospital from 1967 to 1988. Their ages ranged from 1 day to 20 years (median, 12 years); 23 were boys and 10 were girls; and 5 of the 33 (15%) were black. Four of the 33 children had been treated for a previous malignancy. In 3, melanoma arose within a bathing trunk nevus. The extremity was the most common site (13), followed by the trunk (9), head and neck (7), and perineum (1). In 3 patients the primary site could not be determined. Upon initial presentation to St Jude Hospital, 17 patients had localized disease (stage I), 10 had regional node involvement (stage II), and the remaining 6 patients had disseminated disease (stage III). Using both Clark's level and Breslow's thickness as indicators, the incidence, initial stage, prognosis, and survival were compared. By Clark's level, 7 patients, (6 of whom were stage I) were level II or III, and 22 patients were level IV or V. Though 16 of 22 level IV and V patients were initially stage I, 10 patients eventually developed progressive disease. Similar observations were noted when using Breslow's thickness to evaluate the primary. In 5 of 27 evaluable patients, Breslow's depth of invasion was less than 1.5 mm. All 5 of these patients were diagnosed with stage I disease and have not shown progressive disease.

Therapy for cutaneous melanoma: an update

This article reviews the current therapy for cutaneous melanoma. Diagnosis, staging, and prognostic evaluation, which are crucial to proper management, are discussed. Surgical excision is the treatment of choice for primary melanoma. The resection margins should be tailored to tumor thickness. Guidelines for surgery are presented. The controversy about elective regional lymph node dissections is discussed. Limb perfusion, chemotherapy, immunotherapy, radiotherapy, and hormonal therapy as adjuvant treatments of primary melanomas as well as the treatment of disseminated melanomas are reviewed and new developments are highlighted. Guidelines for the management of metastatic melanoma at various sites are given. Special issues such as "pregnancy/estrogen and melanoma" and "borderline melanoma" are discussed and approaches to these problems are suggested. Recommendations are given for the follow-up and counseling of patients with melanoma.

Regional and systemic strategies for metastatic malignant melanoma

Malignant melanoma is no longer a rare neoplasm. Recreational exposure to sunlight is undoubtedly an etiologic factor. Among all cancers, its rate of increase is exceeded only by that of bronchogenic carcinoma. Before administration of systemic therapy, histologic confirmation of the diagnosis and assessment of both the relative medical fitness of the patient and the available psychosocial support are important. Chemotherapeutic and interferon-alpha regimens may offer transient reprieve in 15 to 20% of patients but yield few long-term survivors. Other biologic response modifiers, such as tumor necrosis factor and interleukin 2, are promising but without established consistent efficacy. Postoperative systemic treatment programs for patients at risk for disseminated disease are of no proven benefit in randomized trials and cannot be endorsed outside of the context of a clinical trial. Radiation therapy may provide useful palliation, especially with a fraction of 400 cGy rather than the more traditional dose of 200 cGy/fraction. Selected patients with metastatic disease may benefit from surgical resection, but residual disease after attempted extirpation is usually associated with prolonged disability.