Sentinel node biopsy: not only a staging tool?

Lymphatic mapping and sentinel lymphadenectomy in primary cutaneous melanoma

The management of clinically normal regional lymph nodes in early-stage melanoma has been controversial for over 100 years. Lymphatic mapping and sentinel lymphadenectomy has been developed as a minimally invasive surgical technique to stage regional lymph nodes without the associated morbidity of complete lymph node dissection. Multiple retrospective studies have validated the accuracy of lymphatic mapping and sentinel lymphadenectomy and the importance of the sentinel lymph node as a prognostic tool for melanoma. Several multicenter, prospective, randomized trials are underway to validate the data of the Phase II studies and determine the therapeutic benefit of lymphatic mapping and sentinel lymphadenectomy.

MCW melanoma cocktail for the evaluation of micrometastases in sentinel lymph nodes of cutaneous melanoma

Prevailing reports support the status of sentinel lymph node biopsy as the standard of care in the management of cutaneous melanoma. However, the evaluation of sentinel lymph nodes for melanoma metastases with traditionally used immunomarkers such as S100 protein and HMB45 has proved challenging. The MCW melanoma cocktail (a mixture of MART-1 [1:500], Melan-A [1:100] and tyrosinase [1:50] monoclonal antibodies) has demonstrated a highly discriminatory immunostaining pattern. Contrary to conventionally used immunomarkers such as S100 protein, the MCW melanoma cocktail facilitates detection of even singly scattered melanoma cells in sentinel lymph nodes, not only in permanent sections but also in imprint smears.

Surgery and adjuvant therapies in the treatment of stage IV melanoma: our experience in 84 patients

BACKGROUND AND AIMS

Survival rates of patients with stage IV melanoma are poor: Median survival is 7-8 months and 5-year survival rates about 5%. There is no agreement on the role of surgery at this stage. Most patients with metastatic melanoma are not able to undergo resection and usually are sent to systemic chemo- and immunotherapy.

PATIENTS AND METHODS

Eighty-four patients operated on for stage IV melanoma were evaluated. Of them, 61.9% were submitted to reiterative surgery with 168 operations and 182 surgical procedures overall. A total of 90.5% was submitted to adjuvant therapies according to aggressive and reiterated schedules: chemotherapy, immunotherapy, dendritic cells vaccine, infusion of tumor infiltrating lymphocytes, local therapies as electrochemotherapy.

RESULTS

The mean overall survival (Kaplan-Meier) was 56.7 months (1 year: 72.1%, 3 years: 46.5%, 5 years: 23.16%). The survival of reiterative surgery was significatively longer than single surgery (62.7 vs 42.4 months, median 50.9 vs 16.0), p = 0.03. Multivariated Cox analysis was performed for disease-free interval, repeated surgery, adjuvant therapies, and site of metastasis according to the American Joint Committee on Cancer: Reiterative surgery was shown as an independent prognostic factor (p < 0.05).

CONCLUSION

Metastatic resection associated with adjuvant therapy may improve overall survival and, in some instances, can provide long-term survival, whatever site and numbers of metastasis. In our series, reiterative surgery was more significatively efficient in improving survival than single-time surgery.

Prevention of an additional surgery for regional lymphadenectomy in melanoma: rapid intraoperative immunostaining of sentinel lymph node imprint smears

Background

Sentinel lymph node (SLN) biopsy is performed at many institutions and is considered a standard of care in the management of cutaneous melanoma. The discriminatory immunostaining pattern with the 'MCW Melanoma Cocktail' (a mixture of MART-1 {1:500}, Melan- A {1:100}, and Tyrosinase {1:50} monoclonal antibodies) allows intraoperative immunocytochemical evaluation of imprint smears of SLNs for melanoma metastases. Cohesive cells of benign capsular melanocytic nevi that were also immunoreactive with the cocktail do not exfoliate easily for imprint smear detection.

Methods

We prospectively evaluated 73 lymph nodes (70 SLN & 3 non-SLN) from 41 cases (mean 1.8, 1 to 4 SLNs/case) of cutaneous melanoma using a rapid 17-minute immunostaining previously published protocol. The results were compared with permanent sections also immunostained with 'the cocktail'.

Results

19.5%, 8/41 cases (12%, 9/73 lymph nodes) were positive for melanoma metastases on permanent sections immunostained with the 'MCW melanoma cocktail'. Melanoma metastases in 87.5% (7/8) of these cases were also detected in rapidly immunostained imprint smears, with 100% specificity and 90% sensitivity. None of the 7 SLNs from 7 cases with capsular nevi showed false positive results.

Conclusion

Melanoma metastases could be detected in imprint smears immunostained with 'MCW Melanoma Cocktail' utilizing a rapid intraoperative protocol. The cohesive cells of the capsular nevi do not readily exfoliate and do not lead to false positive interpretation. In a majority of positive cases, a regional lymphadenectomy could have been completed during the same surgery for SLN biopsy and wide excision of primary melanoma site, potentially eliminating the need for an additional surgery.

[Sentinel lymph node biopsy in malignant melanoma--an update]

Ten years after the introduction of the sentinel lymph node biopsy technique in the management of malignant melanoma, it is time to take stock. The complex method has proved itself sufficiently sensitive, although a certain percentage of false-negative histological results have to be taken into account. Presently, it is still a point at issue whether sentinel lymph node biopsy should be regarded as the standard of care in high-risk patients. Three prospective multicentre trials have failed to demonstrate a survival benefit resulting from elective lymph node dissection. In contrast, a retrospective multicentre study has recently shown that patients with node metastases diagnosed by the sentinel procedure benefit from early excision of their nodal disease in terms of overall survival, as compared to patients with delayed dissection of palpable nodes. Studies worldwide have established the pathologic status of the sentinel lymph node biopsy as the most important prognostic factor for recurrence and survival after the excision of primary melanoma. As with any invasive staging procedure, sentinel lymph node biopsy should have demonstrated therapeutic consequences. Unfortunately, an unequivocally acknowledged adjuvant therapy is lacking. Moreover, the impact of complete lymph node dissection after positive sentinel biopsy on survival or local disease control has not yet been clarified.

Intraoperative Detektion von Sentinel-Lymphknoten beim malignen Melanom der Haut-Vitalfarbung allein versus Vitalfarbung plus Gammasonde. Intraoperative detection of sentinel lymph nodes in cutaneous malignant melanoma - blue dye alone versus blue dye plus gamma-detection

BACKGROUND

Compared with intraoperative sentinel lymph node identification using blue dye only, the introduction of a hand-held gamma probe has improved the identification rates. In this retrospective study, further aspects related to the introduction of gamma-guided preparation are analysed in detail.

PATIENTS AND METHODS

81 patients who underwent sentinel biopsy using the blue dye technique were compared to 247 patients whose operations were guided by blue dye and gamma probe.

RESULTS

After the introduction of radio-guided surgery, the sentinel node identification rate increased from 87.7 % to 99.2 % (P < 0.00001). The number of harvested sentinel lymph nodes increased from 1.4 +/- 0.9 to 1.8 +/- 0.09 (P < 0.00001). The "clinical false-negative rate" decreased from 15.8 % to 9.6 %. The percentage of positive completion lymphadenectomy decreased from 50 % to 24.6 %. The risk of postoperative seroma decreased as a consequence of gamma guided preparation (5.1 % versus 15 %, P = 0.01). Regarding overall survival and recurrence-free survival, there were no significant differences between both groups. The 5-year-probability of nodal basin failure was 7.9 % after negative sentinel biopsy and 25.3 % after positive sentinel lymphonodectomy plus consecutive completion lymphadenectomy.

CONCLUSIONS

Combined application of blue dye and gamma-probe improved sensitivity and decreased the risk of postoperative seroma. The probability of recurrence and survival was not influenced by the technique of intraoperative sentinel node identification.

Selective sentinel lymphadenectomy for malignant melanoma, Merkel cell carcinoma, and squamous cell carcinoma

To date, selective sentinel lymphadenectomy (SSL) should be considered a standard approach for staging patients with primary invasive melanoma greater than or equal to 1 mm. It is imperative that the multidisciplinary team master the techniques of preoperative lymphoscintigraphy, intraoperative lymphatic mapping, and postoperative pathologic evaluation of the sentinel lymph nodes (SLNs). An SLN is defined as a blue, "hot" and any subsequent lymph node greater than 10% of the ex vivo count of the hottest lymph node. Any enlarged or indurated lymph node in the nodal basin should be excised. Frozen sections are not recommended. For extremity melanoma, delayed SSL may be performed. Preoperative lymphoscintigraphy for extremity melanoma may be done the night before so that the surgery can be scheduled as the first case of the following day. Every surgeon who uses blue dye should be aware of the potential adverse reaction to isosulfan blue and treatment for such a potential fatal reaction. A complete lymph node dissection is done if the SLN is found to be positive. Elective lymph node dissection (ELND) should not be done if an SSL can be performed as a staging procedure. SSL has further been applied to stage the nodal basin for Merkel cell carcinoma and high-risk squamous cell carcinoma. It is important for investigators involved with the SSL to follow the clinical outcome of these patients, so that the role of SSL can be further defined.

Optimization of an immunostaining protocol for the rapid intraoperative evaluation of melanoma sentinel lymph node imprint smears with the 'MCW melanoma cocktail'

Background

In the management of cutaneous melanoma, it is desirable to complete the regional lymphadenectomy during the initial surgical procedure for wide excision of biopsy site and sentinel lymph node (SLN) biopsy. In this study, we optimized and evaluated a rapid 17 minutes immunostaining protocol. The discriminatory immunostaining pattern associated with the 'MCW Melanoma Cocktail' (mixture of Melan- A, MART- 1, and tyrosinase) facilitated the feasibility of intraoperative evaluation of imprint smears of SLNs for melanoma metastases.

Methods

Imprint smears of 51 lymph nodes from 25 cases (48 SLNs and 3 non-SLNs, 1 to 4 SLNs/case) of cutaneous melanoma were evaluated.

Results

Sixteen percent, 8/51 lymph nodes (28%, 7/25 cases) were positive for melanoma metastases in immunostained permanent sections with the 'MCW melanoma cocktail'. All of these melanoma metastases, except 1 SLN from 1 case, were also detected in rapidly immunostained wet-fixed and air-dried smears (rehydrated in saline and postfixed in alcoholic formalin). The cytomorphology was superior in air-dried smears, which were rehydrated in saline and postfixed in alcoholic formalin. Wet-fixed smears frequently showed air-drying artifacts, which lead to the focal loss of immunostaining. None of the 5 SLNs from 5 cases exhibiting capsular nevi showed a false positive result with immunostained imprint smears.

Conclusions

Melanoma metastases can be detected intraoperatively in both air-dried smears and wet-fixed smears immunostained with the MCW Melanoma cocktail. Air-dried smears rehydrated in saline and postfixed in alcoholic formalin provide superior results and many practical benefits.

Elective radiotherapy provides regional control for patients with cutaneous melanoma of the head and neck

BACKGROUND

In the current study, the authors assessed the efficacy of elective radiotherapy in providing regional (lymph node) control in patients with cutaneous melanoma of the head and neck who were at high risk for lymph node involvement. Toxicity was also assessed.

METHODS

From 1983 to 1998, 157 patients with Stage I or II cutaneous melanoma of the head and neck received elective regional radiotherapy after wide local excision of the primary lesion. None of the patients had received sentinel lymph node biopsy or dissection of the lymph nodes. Their medical records were reviewed retrospectively and analyzed for outcome.

RESULTS

The median follow-up for the current review was 68 months (range, 7-185 months). The disease recurred locally in 9 patients, in the neck lymph nodes in 15 patients, and distantly in 57 patients. The actuarial regional control rate was 89% at both 5 years and 10 years. The actuarial disease-specific survival and distant metastasis-free survival rates were 68% and 63%, respectively, at 5 years and 58% and 49%, respectively, at 10 years. Breslow thickness was a significant determinant of disease-specific survival and distant metastasis-free survival rates. At 10 years, 6% of patients had developed a symptomatic treatment-related complication. There were no treatment-related deaths.

CONCLUSIONS

The results of the current study confirmed the efficacy and safety of elective regional radiotherapy for patients with cutaneous head and neck melanoma predicted to have a high rate of lymph node involvement. Elective irradiation was a viable alternative to elective lymph node dissection. It may also serve as an alternative to sentinel lymph node biopsy, particularly for patients for whom dissection and systemic therapy are not therapeutic options.

Selective sentinel lymphadenectomy for malignant melanoma

To date, selective sentinel lymphadenectomy (SSL) should be considered a standard approach for staging patients with primary invasive melanoma greater than or equal to 1 mm. It is imperative that the multidisciplinary team master the techniques of preoperative lymphoscintigraphy, intraoperative lymphatic mapping, and postoperative pathologic evaluation of the sentinel lymph nodes (SLNs). A SLN is defined as a blue, "hot", or any subsequent lymph node greater than 10% of the in vivo count of the hottest lymph node and as an enlarged or indurated lymph node. Frozen sections are not recommended. For extremity melanoma, delayed SSL may be performed. Preoperative lymphoscintigraphy for extremity melanoma may be done the night before so that surgery can be scheduled as the first case of the following day. Every surgeon who uses blue dye should be cognizant of the potential adverse reaction to isosulfan blue and treatment for such a potential fatal reaction. A complete lymph node dissection is done if the SLN is found to be positive. Elective lymph node dissection should not be done if SSL can be done as a staging procedure. It is important for investigators involved with SSL to follow the clinical outcome of their patients so that the role of SSL can be further defined.