Sentinel Node Biopsy in Patients with Cutaneous Melanoma of the Head and Neck

Lymphatic Mapping and Sentinel Node Identification in Squamous Cell Carcinoma and Melanoma of the Head and Neck

Aim

The aim of our study was to evaluate the role of scintigraphy in lymphatic mapping and in the identification of the sentinel lymph node (SLN) in patients with head and neck cancer.

Methods

Between September 1999 and February 2001 we enrolled 22 consecutive patients with cancer in the head and neck region: five squamous cell carcinomas, one Merkel cell tumor of the cheek, and 16 malignant melanomas. Lymphoscintigraphy was performed three hours before surgery after injection of 30-50 MBq of 99mTc-Nanocoll in 0.3 mL; the dose was fractionated by injecting the radiotracer at two points around the lesion. Static acquisition (anterior and/or lateral views, 512 × 512 matrix, 5 mins pre-set time) was started immediately after the injections so as to visualize the pathways of lymphatic drainage. The skin projection of the SLN was marked with ink. Intraoperative SLN detection was performed with perilesional injection of patent blue.

Results

SLNs were found with lymphoscintigraphy in all patients. Thirty-three SLNs were identified: one occipital node, three nodes at the base of the tongue, 10 superficial lateral nodes (external jugular), five submandibular nodes, five submental nodes, three mastoid nodes and six supraclavicular nodes. Biopsy was performed in 21/22 patients. In 20/22 patients the first lymph nodes were visualized in the proximal cranial regions (retroauricular, jugular and submandibular) at five minutes post injection. The SLN positivity rate was 13.6% (three patients). All patients with tumor-positive SLNs were submitted to radical dissection. Poor concordance in the detection of sentinel nodes was observed with patent blue.

Conclusions

The flow of nanocolloid in the lymph vessels of the head is rapid. In our experience immediate scintigraphic imaging was essential to visualize the pathways of lymphatic drainage and the first SLN. Radioguided SLN biopsy is therefore recommended within three hours. Injection of patent blue is inadvisable because of the poor concordance with lymphoscintigraphy and the risk of permanent tattooing of the face.

Sentinel lymph node biopsy for melanoma of the head and neck

Since its first description nearly two centuries ago, melanoma has been a difficult disease to diagnose and treat. With the incidence and mortality rates slowly increasing, understanding this disease is more important than ever. Herein, the current diagnostic and treatment recommendations for melanoma of the head and neck are reviewed, with special emphasis on the use of sentinel lymph node biopsy (SLNB). For the past decade, SLNB has been a well-accepted procedure in the treatment of truncal and extremity melanoma, providing useful information for both treatment and prognosis. Still, despite its clear role in the rest of the body, the role of SLNB has not yet been fully defined in the management of melanoma of the head and neck. The complexity of lymphatic drainage patterns and the frequent need to remove sentinel lymph nodes from the parotid gland, thus placing the facial nerve at risk, have made head and neck surgical oncologists slow to adopt this method. However, current data from several trials indicate that in the head and neck, sentinel lymph nodes can be identified reliably approximately 98% of the time using intraoperative lymphatic mapping. In addition, the false-negative and complication rates are appropriately low. SLNB allows for accurate staging of patients, informed discussions of prognosis and the use of adjuvant therapies, including radiation and interferon-alpha2b. For these reasons, the authors believe that SLNB will become the standard-of-care for head and neck melanoma as well as for other body sites.

Sentinel Node Biopsy for Head and Neck Melanoma

Objective. This systematic review was conducted to examine the test performance of sentinel node biopsy in head and neck melanoma, including the identification rate and false-negative rate.

Data Sources. PubMed, EMBASE, ASCO, and SSO database searches were conducted to identify studies fulfilling the following inclusion criteria: sentinel node biopsy was performed, lesions were located on the head and neck, and recurrence data for both metastatic and nonmetastatic patients were reported.

Review Methods. Dual-blind data extraction was conducted. Primary outcomes included identification rate and test performance based on completion neck dissection or nodal recurrence.

Results. A total of 3442 patients from 32 studies published between 1990 and 2009 were reviewed. Seventy-eight percent of studies were retrospective and 22% were prospective. Trials varied from 9 to 755 patients (median 55). Mean Breslow depth was 2.53 mm. Median sentinel node biopsy identification rate was 95.2%. More than 1 basin was reported in 33.1% of patients. A median of 2.56 sentinel nodes per patient were excised. Sentinel node biopsy was positive in 15% of patients. Subsequent completion neck dissection was performed in almost all of these patients and revealed additional positive nodes in 13.67%. Median follow-up was 31 months. Across all studies, predictive value positive for nodal recurrence was 13.1% and posttest probability negative was 5%. Median false-negative rate for nodal recurrence was 20.4%.

Conclusion. Sentinel node biopsy of head and neck melanoma is associated with an increased false-negative rate compared with studies of non–head and neck lesions. Positive sentinel node status is highly predictive of recurrence.

Candidate???s Thesis: The Application of Sentinel Node Radiolocalization to Solid Tumors of the Head and Neck: A 10-Year Experience

OBJECTIVES/HYPOTHESIS

The goals of the research study were to develop an easily mastered, accurate, minimally invasive technique of sentinel node radiolocalization with biopsy (SNRLB) in the feline model; to compare it with blue-dye mapping techniques; and to test the applicability of sentinel node radiolocalization biopsy in three head and neck tumor types: N0 malignant melanoma, N0 Merkel cell carcinoma, and N0 squamous cell carcinoma.

STUDY DESIGN

Prospective consecutive series studies were performed in the feline model and in three head and neck tumor types: N0 malignant melanoma (43 patients), N0 Merkel cell carcinoma (8 patients), and N0 squamous cell carcinoma (20 patients).

METHODS

The technique of sentinel node radiolocalization with biopsy was analyzed in eight felines and compared with blue-dye mapping. Patterns of sentinel node gamma emissions were recorded. Localization success rates were determined for blue dye and sentinel node with radiolocalization biopsy. In the human studies, all patients had sentinel node radiolocalization biopsy performed in a similar manner. On the morning of surgery, each patient had sentinel node radiolocalization biopsy of the sentinel lymph node performed using an intradermal or peritumoral injection of technetium Tc 99m sulfur colloid. Sentinel nodes were localized on the skin surface using a handheld gamma detector. Gamma count measurements were obtained for the following: 1) the "hot" spot/node in vivo before incision, 2) the hot spot/node in vivo during dissection, 3) the hot spot/node ex vivo, 4) the lymphatic bed after hot spot/node removal, and 5) the background in the operating room. The first draining lymph node(s) was identified, and biopsy of the node was performed. The radioactive sentinel lymph node(s) was submitted separately for routine histopathological evaluation. Preoperative lymphoscintigrams were performed in patients with melanoma and patients with Merkel cell carcinoma. In patients with head and neck squamous cell carcinoma, the relationship between the sentinel node and the remaining lymphatic basin was studied and all patients received complete neck dissections. The accuracy of sentinel node radiolocalization with biopsy, the micrometastatic rate, the false-negative rate, and long-term recurrence rates were reported for each of the head and neck tumor types. In the melanoma study, the success of sentinel node localization was compared for sentinel node radiolocalization biopsy, blue-dye mapping, and lymphoscintigraphy. In the Merkel cell carcinoma study, localization rates were evaluated for sentinel node radiolocalization biopsy and lymphoscintigraphy. In the head and neck squamous cell carcinoma study, the localization rate of sentinel node radiolocalization biopsy and the predictive value of the sentinel node relative to the remaining lymphatic bed were determined. All results were analyzed statistically.

RESULTS

Across the different head and neck tumor types studied, sentinel node radiolocalization biopsy had a success rate approaching 95%. Sentinel node radiolocalization biopsy was more successful than blue-dye mapping or lymphoscintigraphy at identifying the sentinel node, although all three techniques were complementary. There was no instance of a sentinel node-negative patient developing regional lymphatic recurrence. In the head and neck squamous cell carcinoma study, there was no instance in which the sentinel node was negative and the remaining lymphadenectomy specimen was positive.

CONCLUSION

In head and neck tumors that spread via the lymphatics, it appears that sentinel node radiolocalization biopsy can be performed with a high success rate. This technique has a low false-negative rate and can be performed through a small incision. In head and neck squamous cell carcinoma, the histological appearance of the sentinel node does appear to reflect the regional nodal status of the patient.

False-negative sentinel node in patients with vulvar cancer: a case study

Evidence from recent studies indicates that the technique of sentinel node biopsy might be a useful solution for detecting lymph node status for primary vulvar cancer without having to perform radical inguinal lymphadenectomy. The patient in this report underwent sentinel node biopsy, then bilateral inguino-femoral node dissection, and, lastly, radical vulvectomy. The histologic analysis showed a well differentiated squamous cell carcinoma with metastases in one right inguinal node and one left inguinal node and a false-negative right sentinel node. Technically the biopsy of groin sentinel nodes should be quite easy to perform. The use of preoperative lymphoscintigraphy and the intraoperative use of the gamma probe combined with blue dye helps considerably in identifying lymphatic drainage and the sentinel node for vulvar cancer. Further results are needed to confirm the value of sentinel node dissection in the treatment of early stage vulvar cancer.

[Preliminary results of the relevance the sentinel node in head and neck tumors]

OBJECTIVES

The objective of this study is to assess the value of the sentinel node (SN) in head and neck tumours and to create a lymphatic mapping of these tumors.

PATIENTS AND METHODS

We prospectively studied 13 patients with head and neck tumours N0. We divided these patients in two groups depending on the location of the primary tumour. We injected colloidal particles of serum albumin labeled with Tc-99 peritumoraly and we located the SN intraoperatively. The SN was then sent for anatomopathological study.

RESULTS

In the oropharynx and oral cavity group, with 5 patients, the SN correctly predicted the pathological status of the neck in all of them. In the group of larynx and hypopharynx, with 8 patients, in 6, the SN correctly predicted the pathological status of the neck. In 2 patients, the SN was negative for metastases but there were metastases in the neck dissection.

CONCLUSIONS

This technique represents an advance over selective dissection as an accurate method of neck staging, but its value in this field remains unclear.