Eight Years' Experience of Sentinel Lymph Node Biopsy in Melanoma Using Lymphoscintigraphy and Gamma Probe Detection After Radiocolloid Mapping

Melanoma sentinel lymph node biopsy in the modern era

The initial route of metastasis for many cancers, including melanoma, is via regional lymphatic channels. This fact, recognized more than a century ago, has spurred tremendous interest in the optimal method of assessing and treating lymph nodes and eventually led to the development of lymphatic mapping and sentinel lymph node (SLN) biopsy. The potential utility of nodal treatment includes providing the most accurate staging or prognostic information and removing early metastases in order to halt the cascade of metastatic spread in an effort to save the patient's life. In the past, pathologic assessment of regional lymph nodes required removal of all regional nodes, a procedure that results in moderate levels of short and long-term morbidity. SLN biopsy allows not only a minimally invasive method of nodal assessment, but one more accurate than full node dissection as it permits more intensive pathologic scrutiny of the tissue. The question of the therapeutic effect of SLN biopsy has been a subject of much controversy. There is clear evidence that SLN biopsy improves relapse-free survival in melanoma, but its effect on melanoma-specific and overall survival remains less clear.

The Use and Technique of Sentinel Node Biopsy for Skin Cancer

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Understand the indications for and prognostic value of sentinel lymph node biopsy in skin cancer. 2. Learn the advantages and disadvantages of various modalities used alone or in combination when performing sentinel lymph node biopsy. 3. Understand how to perform sentinel lymph node biopsy in skin cancer patients.

SUMMARY

Advances in technique used to perform sentinel lymph node biopsy to assess lymph node status have led to increased accuracy of the procedure and improved patient outcomes.

Prognostic significance of sentinel node biopsy status in cutaneous melanoma: a 21-years prospective study from a single institution

AIM

To analyze the accuracy of the sentinel lymphatic node biopsy (SLNB) and to investigate predictive factors for sentinel node (SN) status and prognostic factors for recurrence-free survival (RFS) and disease-specific survival (DSS) in patients with melanoma.

MATERIAL AND METHODS

Between June 1997 and June 2017, 440 consecutive patients, who underwent SLNB by a single surgical team, were prospectively included. Descriptive and survival analysis were performed.

RESULTS

119 of 440 patients (26%) had positive SN. SLNB's false-negative rate was 6.3%. Breslow thickness, Clark´s level, ulceration and histological subtype were statistically significant predictive factors of SN metastases. In a multivariate analysis, positive SN (HR = 2.21, p = 0.01), deeper Breslow thickness (HR = 2.05, p = 0.013), male gender (RR = 2.05, p = 0.02), and higher Clark's level (HR = 2.30, p = 0.043) were significantly associated with decreased RFS; and positive SN (HR = 2.58, p < 0.001), deeper Breslow thickness (HR = 2.57, p = 0.006) and male gender (HR = 1.93, p = 0.006) were associated with lower DSS.

CONCLUSION

SLNB is a reliable and reproducible procedure with high sensitivity (93.7%). Positive SN metastases, Breslow thickness and male gender were statistically associated with poorer outcomes. Male gender was an independent prognostic factor of tumor thickness or SN status.

Cutaneous Surgery in Patients Who Are Pregnant or Breastfeeding

Dermatologic surgery in pregnant/postpartum patients requires deliberate consideration. Although surgery can be safely performed during any trimester, the second trimester and immediate postpartum period is optimal. Surgery should not be delayed for melanoma/high-risk skin cancers. Perioperative positioning, analgesic, antiseptic, and antibiotic selection should be deliberate to avoid risk to the patient/fetus/infant. The left lateral tilt position reduces aortocaval compression syndrome. Lidocaine and epinephrine can be used safely. Alcohol and chlorhexidine are considered safe. Antibiotics commonly used in skin surgery are safe in pregnancy and lactation. Acetaminophen is first line for pain management. Nonsteroidal antiinflammatory drugs should be avoided.

Sentinel lymph node biopsy in melanoma: Which hot nodes should be harvested and is blue dye really necessary?

OBJECTIVES

The '10% rule' has become widely accepted by surgeons performing sentinel lymph node biopsy (SLNB) for melanoma. The purpose of this study was to compare the '10% rule' with alternative node harvesting criteria. In particular, we were interested to see whether the use of blue dye had any impact on the sensitivity of the test and whether it is necessary to remove all hot nodes.

METHODS

We reviewed 537 SLNBs performed for primary melanoma from 2009-2015. SLNB was offered to all patients with 1-4 mm Breslow thickness melanoma and sentinel nodes were harvested according to the '10% rule'.

RESULTS

One hundred sixteen patients (22%) had at least one positive sentinel node and there were 45 positive nodal basins from which more than one sentinel node had been harvested. Excluding blue dye and sampling only hot nodes would have enabled a 5% reduction in nodes harvested, without any compromise in the sensitivity of the test. However, applying harvesting criteria whereby not all hot nodes are taken was associated with a loss of sensitivity, with positive sentinel nodes being missed and patients understaged.

CONCLUSIONS

Our data do not support the continued use of blue dye in SLNB for melanoma, as it does not improve the sensitivity of the test. This series adds to growing evidence, suggesting that the '10% rule' with the inclusion of blue nodes should be reconsidered and that radiocolloid tracer alone is sufficient for sentinel node localisation.