Modification of lymphoscintigraphic sentinel node identification before and after excisional biopsy of primary cutaneous melanoma

Nonvisualized sentinel node on preoperative lymphoscintigraphy in primary cutaneous melanoma: an 11-year retrospective survey

BACKGROUND

Sentinel lymph node (SLN) biopsy in cutaneous melanoma patients evaluates the regional draining basin for occult micrometastatic disease. Occasionally, nonidentification of SLN impairs the acquisition of this important prognostic factor.

OBJECTIVES

To investigate the outcomes of melanoma patients with negative lymphoscintigraphic findings and patients who underwent SLN biopsy from 2004 to 2015 ( n  = 1200) were retrospectively reviewed for tumor characteristics and clinical outcomes.

METHODS

Patients with nonvisualized lymph nodes (NV group) who underwent only preoperative lymphoscintigraphy were separated and compared with a cohort drawn from all melanoma patients who completed the surgical procedure within the same period (V group).

RESULTS

A negative lymphoscintigraphic scan was observed in 38 cases (3.2% of all patients). The NV group showed a significantly older age (median 66.0 vs. 48.3 years; P  < 0.0001). Head and neck melanomas were more frequent in the NV group compared to the control group (25.1 vs. 7.8%; P  = 0.009). Tumor characteristics such as ulceration and Breslow thickness do not influence the lymphoscintigraphy result. No differences were found in overall survival (OS) and disease-free survival (DFS) between the groups.

CONCLUSIONS

The nonvisualization of regional lymph nodes by lymphoscintigraphy is more frequent in older patients with head and neck melanomas. From the clinical point of view, no specific recommendation emerged for patients' management because the nonvisualization of the SLN did not show a significant influence on DFS and OS rates. However, lack of knowledge of lymph node status suggests performing a tighter follow-up eventually by ultrasound evaluation of all potential lymph node drainage basins.

The Devil's in the Details: Discrepancy Between Biopsy Thickness and Final Pathology in Acral Melanoma

PURPOSE

We hypothesized that initial biopsy may understage acral lentiginous melanoma (ALM) and lead to undertreatment or incomplete staging. Understanding this possibility can potentially aid surgical planning and improve primary tumor staging.

METHODS

A retrospective review of primary ALMs treated from 2000 to 2017 in the US Melanoma Consortium database was performed. We reviewed pathology characteristics of initial biopsy, final excision specimens, surgical margins, and sentinel lymph node biopsy (SLNB).

RESULTS

We identified 418 primary ALMs (321 plantar, 34 palmar, 63 subungual) with initial biopsy and final pathology results. Median final thickness was 1.8 mm (range 0.0-19.0). There was a discrepancy between initial biopsy and final pathology thickness in 180 (43%) patients with a median difference of 1.6 mm (range 0.1-16.4). Final T category was increased in 132 patients (32%), including 47% of initially in situ, 32% of T1, 39% of T2, and 28% of T3 lesions. T category was more likely to be increased in subungual (46%) and palmar (38%) melanomas than plantar (28%, p = 0.01). Among patients upstaged to T2 or higher, 71% had ≤ 1-cm margins taken. Among the 27 patients upstaged to T1b or higher, 8 (30%) did not have a SLNB performed, resulting in incomplete initial staging.

CONCLUSIONS

In this large series of ALMs, final T category was frequently increased on final pathology. A high index of suspicion is necessary for lesions initially in situ or T1 and consideration should be given to performing additional punch biopsies, wider margin excisions, and/or SLNB.

Does the time interval between sentinel lymph node biopsy and completion lymph node dissection affect outcome in malignant melanoma? A retrospective cohort study

Nodal clearance was recommended after positive sentinel lymph node biopsy (SLNB) despite further metastases to the regional lymph node basin being found in only 6-21% in the literature. This retrospective study was conducted to determine the role of the time interval between excision of primary melanoma and confirmed metastasis in the sentinel lymph node biopsy as well as the one between positive sentinel lymph node biopsy (SLNB-positive patients) and subsequent completion lymph node dissection (CLND) on the presence of metastases. The monocentric analysis included 121 patients with a history of completion lymph node dissection after positive SLNB from January 2005 to October 2013. Additional metastases in the regional lymph node basin (non-sentinels) were found in 14.05% (n = 17). Significant risk factors for the presence of metastases in CLND were the time between confirmed primary tumour to metastasis in sentinel lymph nodes (SLN) (p = 0.0034), N-category of TNM-classification (p = 0.0066) and independent of thickness of primary tumour (p = 0.11). If SLNB was performed up to forty-three days after confirmed primary melanoma, subsequent lymph node dissection was positive in less than 9.1%. When SLNB was performed with a delay of more than 80 days, all patients had metastases in the CLND specimens. Our data analysis suggests that delays in subsequent procedures of SLNB after diagnosis of primary melanoma may have a greater impact on positivity of non-sentinel lymph nodes than previously assumed. Our retrospective analysis may indicate the reconsideration of time schedule in the management of primary melanoma to potentially avoid local relapse in the draining lymph node region after positive SLNB.

Single-stage excision and sentinel lymph node biopsy in cutaneous melanoma in selected patients: a retrospective case-control study

Sometimes, diagnostic excision of a primary melanoma would already necessitate skin grafting or transposition skin flaps, especially in areas with an esthetic or functional importance. The utility of sentinel lymph node biopsy (SLNB) after skin reconstruction is controversial. We carried out a single-institution retrospective case-control study. In patients with a wide primary lesion at high clinical-dermatoscopic suspicion for invasive melanoma in anatomical region in which a reconstruction with a skin graft or a flap is required, we proposed the performance of a confocal microscopy examination and an incisional biopsy of the primary lesion. If these diagnostic methodologies confirmed the suspicion of melanoma, lymphatic mapping was performed before the wide excision (WE) of the primary lesion, and WE and SLNB were performed during the same operative procedure. The database evaluation showed 496 patients who had undergone a previous complete local excision and a subsequent SLNB (two-stage group), whereas 61 patients underwent WE and SLNB during the same surgical time (one-stage group). Histological results of the excisional biopsy confirmed the diagnosis of melanoma in all patients of the one-stage group. The false-negative rate was lower in the one-stage group (5.5%) than in the two-stage group (16.7%). Patients of the two groups showed a similar recurrence-free and overall survival period even when corrected for clinic-demographical variables. The concomitant execution of SLNB and WE after confocal microscopy examination and incisional biopsy appears to be a safe and accurate procedure in patients with a wide primary melanoma that requires a skin flaps or a skin graft to cover the residual defect.