Lymph node dissection in malignant melanoma

Lessons learned from the Sunbelt Melanoma Trial

The Sunbelt Melanoma Trial is an ongoing multicenter prospective randomized trial that involves 79 centers and over 3600 patients from across the United States and Canada. This is one of the first large randomized studies to incorporate molecular staging using reverse transcriptase polymerase chain reaction (RT-PCR). While the results related to the primary endpoints of the study are not yet available, several analyses have shed light on many aspects of sentinel lymph node (SLN) biopsy and melanoma prognostic factors. In particular, we have developed a practical definition of sentinel nodes based on the degree of radioactivity. We have established the low rate of postoperative complications associated with SLN biopsy as compared to complete lymph node dissection. We have identified factors that predict the presence of SLN metastases. In contrast, we have been unable to identify factors that indicate a low risk of non-sentinel node metastases in patients with a positive sentinel node, suggesting that completion lymphadenectomy is appropriate for such patients. We have further established the value of identifying interval or in-transit sentinel nodes, which can be the only site of nodal metastasis. We have evaluated the particular challenges associated with SLN biopsy of head and neck melanomas, have evaluated the patterns of early recurrence, and have identified an interesting correlation between increasing patient age and a number of prognostic factors. Future analyses will evaluate the benefit of early therapeutic lymphadenectomy and early institution of adjuvant interferon alfa-2b therapy, as well as the validity of molecular staging.

Complications associated with sentinel lymph node biopsy for melanoma

BACKGROUND

Sentinel lymph node (SLN) biopsy has become widely accepted as a method of staging the regional lymph nodes for patients with melanoma. Although it is often stated that SLN biopsy is a minimally invasive procedure associated with few complications, a paucity of data exists to specifically determine the morbidity associated with this procedure. This analysis was performed to evaluate the morbidity associated with SLN biopsy compared with completion lymph node dissection (CLND).

METHODS

Patients were enrolled in the Sunbelt Melanoma Trial, a prospective multi-institutional study of SLN biopsy for melanoma. Patients underwent SLN biopsy and were prospectively followed up for the development of complications associated with this technique. Patients who had evidence of nodal metastasis in the SLN underwent CLND. Complications associated with SLN biopsy alone were compared with those associated with SLN biopsy plus CLND.

RESULTS

A total of 2120 patients were evaluated, with a median follow-up of 16 months. Overall, 96 (4.6%) of 2120 patients developed major or minor complications associated with SLN biopsy, whereas 103 (23.2%) of 444 patients experienced complications associated with SLN biopsy plus CLND. There were no deaths associated with either procedure.

CONCLUSIONS

SLN biopsy alone is associated with significantly less morbidity compared with SLN biopsy plus CLND.

Current therapy of cutaneous melanoma

Melanoma is a growing public health problem. Optimal care of the melanoma patient is multidisciplinary, but plastic surgeons and other surgical specialties play a central role in the management of these patients. Although surgery remains the mainstay of therapy for melanoma, several recent clinical studies have helped to clarify the biology of the disease and have changed the patterns of care for patients with melanoma. The advent of lymphatic mapping for interrogation of regional lymph nodes and interferon as the first effective postsurgical adjuvant therapy have had a major impact on the care of melanoma in the United States and elsewhere. This article will review the current clinical approach and therapy for cutaneous melanoma. The diagnosis, prognostic variables, staging evaluation, current surgical and medical treatment, and follow-up guidelines for patients with all stages of melanoma are reviewed. Recent studies, controversies, and directions of future investigational therapies will be discussed.

Initial assessment of positron emission tomography for detection of nonpalpable regional lymphatic metastases in melanoma

BACKGROUND

The purpose of this pilot study is to determine the feasibility of positron emission tomography with fluorodeoxyglucose (FDG-PET) for detection of nonpalpable regional lymph node metastases in patients with melanoma.

METHODS

Adult patients with histologically proven cutaneous melanoma planned to undergo surgical lymphadenectomy for treatment of nonpalpable subclinical or residual metastatic melanoma in regional lymph node basin(s) participated. Each patient underwent attenuation-corrected PET imaging of the regional lymph node basin(s) with F18 fluorodeoxyglucose (FDG) followed by complete surgical lymphadenectomy. FDG-PET scans were interpreted prospectively by an experienced nuclear medicine physician. FDG-PET scan interpretations and histologic results were then correlated.

RESULTS

Eleven patients underwent 12 FDG-PET scans followed by 12 operations to clear 14 regional lymph node basins. FDG-PET correctly predicted the presence of metastatic melanoma in seven of seven surgical specimens. FDG-PET scans correctly predicted the absence of disease in seven of seven histologically negative node basins. Sensitivity was 1.0; specificity was 1.0.

CONCLUSIONS

This study suggests that increased fluorodeoxyglucose uptake in palpably unremarkable regional lymph node basins in patients with melanoma is highly suggestive of metastatic disease.

Malignant melanoma prognostic factors 5: clinical staging

Regional lymph node enlargement, as determined by palpation, is a useful prognostic factor--even if these nodes are histologically free of metastases. This is true not only for malignant melanoma but also for mycosis fungoides and carcinoma of the vulva.

[Surgical treatment of malignant melanomas of the skin]

The authors report on the most important problems of surgical treatment in primary melanomas. Great importance should be attributed to surgery especially in I. stage melanomas, just because it might influence further development of the disease--they accentuate. This argument will justify the performance of an elective lymphonodal dissection if there are some risk factors (e.g. depth of invasion, tumour thickness, exulceration, anatomic subsites, etc.) suggesting the possible presence of microscopic regional metastases. Within the frame of a clinical study a large number of literary data are also discussed.

Indications for elective groin dissection in clinical stage I patients with malignant melanoma of the lower extremity treated by hyperthermic regional perfusion

From 1973 through 1979, inguinal node biopsy was performed to stage the disease process in 179 clinical Stage I patients with malignant melanoma of the lower extremity, who were all treated by hyperthermic regional perfusion as well. Of the 179 tumors, 12% were intermediate risk (0.75-1.44 mm) and 88% were high risk (greater than or equal to 1.5 mm); all had a Clark level of IV or V. The Rosenmüller node at the caudal margin of the saphenous hiatus was elected for inguinal node biopsy. This biopsy supplies a fair amount of information about the entire inguinal node region: a malignant node was found in 16 patients (9%); no other metastatic nodes were found in 11 (73%) of 15 subsequent therapeutic node dissections; the 16th had metastatic parailiac nodes as well. Two patients of the remaining 163 had only metastatic parailiac nodes, without metastatic inguinal nodes. Of the remaining 161 histologic Stage I patients, 23 (14%) developed inguinal node metastases in the course of the follow-up. In 17 (74%) these metastases occurred within 2 years of perfusion. Ten of the 23 showed simultaneous general metastases. The vast majority of the inguinal node metastases developed in patients with a tumor greater than or equal to 5 mm. The 5-year survival was 81%, i.e. 84% in females versus 69% in males, the difference being significant (P less than 0.01). A tumor thickness greater than or equal to 5 mm implied a significantly less favorable prognosis as to development of inguinal node metastases associated with general metastases than a tumor thickness less than 5 mm. The benefit of the inguinal node biopsy was related to the difference in 5-year survival between the group with inguinal node metastases at perfusion (69%) and the group who developed inguinal node metastases during the follow-up (24%). The difference was great (45%) but statistically not significant. The data seem to warrant the conclusion that, after perfusion therapy, inguinal node biopsy is sufficient to stage the disease process at a tumor thickness less than or equal to 5 mm. Given a tumor thickness less than or equal to 5 mm, elective groin dissection might improve the chance of survival.