Sentinel node detection in N0 cancer of the pharynx and larynx

Intra-operative lymphatic mapping and sentinel node biopsy in laryngeal carcinoma using radiotracer injection

OBJECTIVE

The purpose of this study was to determine the value of sentinel lymph node biopsy (SLNB) in the laryngeal SCC, using intra-operative peri-tumoral injection of Tc-99m-phytate.

METHODS

Patients with biopsy-proven squamous cell carcinoma of the larynx were included. On the day of surgery, after anesthesia induction, suspension laryngoscopy was performed to inject 74 MBq/0.4 ml Tc-99m-phytate in four aliquots into the sub-mucosal peri-tumoral location. After a 10-min wait, a portable gamma probe was used to locate sentinel nodes. Subsequently, all patients underwent laryngectomy and neck dissection. Both sentinel nodes and non-sentinel nodes were examined using hematoxylin and eosin (H&E) staining.

RESULTS

Twenty-six patients with a diagnosis of laryngeal carcinoma were included in the study. The SLN detection rate was 65.4%, with a 100% detection rate in the supraglottic region and a 52.6% detection rate for glottis/transglottic patients. Permanent pathology results showed lymph node involvement in four patients, but only one patient had a negative result in the SLNB, resulting in an overall false negative rate of 25%. The sensitivity of the SLN technique was 75% overall, 100% in the supraglottic region, and 67% in the glottis/transglottic region.

CONCLUSION

The accuracy and feasibility of SLNB may be related to the location of the tumors in the larynx. For supraglottic tumors, the technique seems to be feasible with a low false negative rate. For glottis/transglottic tumors, both the detection rate and false negative rate seem to be suboptimal. Further studies are needed to validate our results.

Unilateral versus bilateral nodal irradiation: Current evidence in the treatment of squamous cell carcinoma of the head and neck

Cancers of the head and neck region often present with nodal involvement. There is a long-standing convention within the community of head and neck radiation oncology to irradiate both sides of the neck electively in almost all cases to include both macroscopic and microscopic disease extension (so called elective nodal volume). International guidelines for the selection and delineation of the elective lymph nodes were published in the early 2000s and were updated recently. However, diagnostic imaging techniques have improved the accuracy and reliability of nodal staging and as a result, small metastases that used to remain undetected and were thus in the past included in the elective nodal volume, will now be included in high-dose volumes. Furthermore, the elective nodal areas are situated close to the parotid glands, the submandibular glands and the swallowing muscles. Therefore, irradiation of a smaller, more selected volume of the elective nodes could reduce treatment-related toxicity. Several researchers consider the current bilateral elective neck irradiation strategies an overtreatment and show growing interest in a unilateral nodal irradiation in selected patients. The aim of this article is to give an overview of the current evidence about the indications and benefits of unilateral nodal irradiation and the use of SPECT/CT-guided nodal irradiation in squamous cell carcinomas of the head and neck.

Total Laryngectomy-Still Cutting-Edge?

Surgical removal of the larynx (total laryngectomy) offers a curative approach to patients with advanced laryngeal and hypopharyngeal (squamous cell) cancer without distant metastases. Particularly in T4a carcinoma, laryngectomy seems prognostically superior to primary radio(chemo)therapy. Further relevant indications for laryngectomy include massive laryngeal dysfunction associated with aspiration and recurrence after radio(chemo)therapy, resulting in salvage surgery. The surgical procedure including neck dissection is highly standardised and safe. The resulting aphonia can be compensated by functional rehabilitation (e.g., voice prosthesis) associated with a significant quality of life improvement. This article presents an overview of indications, preoperative diagnostics, surgical procedures, including new developments (robotics), possible complications, the choice of adjuvant treatment, alternative therapeutic approaches, rehabilitation and prognosis. In summary, total laryngectomy still represents a relevant surgical procedure in modern head and neck oncology.

Novel Diagnostic Approaches for Assessment of the Clinically Negative Neck in Head and Neck Cancer Patients

In head and neck cancer, the presence of nodal disease is a strong determinant of prognosis and treatment. Despite the use of modern multimodality diagnostic imaging, the prevalence of occult nodal metastases is relatively high. This is why in clinically node negative head and neck cancer the lymphatics are treated “electively” to eradicate subclinical tumor deposits. As a consequence, many true node negative patients undergo surgery or irradiation of the neck and suffer from the associated and unnecessary early and long-term morbidity. Safely tailoring head and neck cancer treatment to individual patients requires a more accurate pre-treatment assessment of nodal status. In this review, we discuss the potential of several innovative diagnostic approaches to guide customized management of the clinically negative neck in head and neck cancer patients.

Lymphoscintigraphy for Sentinel Node Mapping in Head and Neck Cancer

The aim of this comprehensive review is to describe and analyze the role of the sentinel node mapping in head and neck cancers. For this purpose, head and neck neoplasms have been categorized in cutaneous malignancies and neoplasms of the upper aerodigestive tract. A concise description of lymphatic drainage will be the "prelude" for each section, as well as the description of the injection techniques, when specific. Concisely, the attention has been focused on detection rate of the sentinel node by lymphoscintigraphy for each cancer, and for those patients in which the sentinel lymph node has been identified, true-positives rates, false-negative rates, and overall accuracy has been pointed out. Overall, in cutaneous neoplasms of the head and neck, the detection rate is higher than 90%, however the false-negative rate is still an issue, in particular in melanoma, inducing the need for newer developments. In fact, new tracers and techniques are already available, while prospective multicenter trials exploring the outcome impact are needed in the near future. For the upper aerodigestive tract and in particular oral cavity and oropharynx, sentinel lymph node identification by lymphoscintigraphy allows avoiding unnecessary neck dissection and/or node irradiation. Even in this case, the main limit remains the risk of false-negative rates. While, for patients affected by laryngeal and hypopharyngeal cancers the data seem very limited and, although the feasibility has been demonstrated, performances of this lymphoscintigraphy still need to be confirmed by multicenter studies.

[Laryngectomy-still state of the art?]

Total laryngectomy provides a curative approach for patients with advanced laryngeal and hypopharyngeal cancer without distant metastasis. Especially in stage cT4a disease, laryngectomy is superior to primary radio(chemo)therapy in retrospective studies. Further relevant indications for the procedure are tumor-related laryngeal dysfunction such as dysphagia and aspiration, as well as cancer recurrence after primary radio(chemo)therapy. The surgical procedure is highly standardized, with an appropriate safety profile. The subsequent loss of voice must be compensated by voice rehabilitation (voice prosthesis, ructus). The current overview provides information about indications for laryngectomy, preoperative clinical diagnostics, the surgical procedure, complications, alternative treatment, rehabilitation, and prognosis. Total laryngectomy remains a standard procedure in modern head and neck oncology.

[Neck dissection-Surgical treatment of cervical lymphatic drainage pathways]

Neck dissection (ND) is an essential component of treatment in head and neck squamous cell carcinoma (HNSCC). The extent of ND depends on primary tumor location and T and N stage. Trials have demonstrated improved survival for cN+ status with therapeutic ND as well as for cN0 status with selective ND if the primary has a high incidence of occult metastasis. The accuracy of the procedure is of prognostic relevance. In the prognostic model of the TNM classification, the parameter "N" does not only reflect the number of affected lymph nodes, but also their size and extranodal tumor extension. Due to its better prognosis, a positive human papillomavirus (HPV) status is also incorporated in the present TNM classification. In order to minimize morbidity after ND, one seeks to limit its extent without reducing survival time. To this aim, sentinel node biopsy or surveillance with positron-emission computed tomography (PET-CT) in cN0 necks or after primary radio(chemo)therapy are being investigated.

Sentinel Lymph Node Biopsy: A new approach in the management of head and neck cancers

Cervical lymph node metastasis affects the prognosis and overall survival rate of and therapeutic planning for patients with head and neck squamous cell carcinomas (HNSCCs). However, advanced diagnostic modalities still lack accuracy in detecting occult neck metastasis. A sentinel lymph node biopsy is a minimally invasive auxiliary method for assessing the presence of occult metastatic disease in a patient with a clinically negative neck. This technique increases the specificity of neck dissection and thus reduces morbidity among oral cancer patients. The removal of sentinel nodes and dissection of the levels between the primary tumour and the sentinel node or the irradiation of target nodal basins is favoured as a selective treatment approach; this technique has the potential to become the new standard of care for patients with HNSCCs. This article presents an update on clinical applications and novel developments in this field.

Sentinel Node Biopsy as Staging Tool in a Multimodality Treatment Approach to Cancer of the Oral Cavity and the Oropharynx

OBJECTIVES: Feasibility of sentinel lymph node (SLN) biopsy in head and neck cancer as a staging tool embedded in a multimodality regimen including neoadjuvant intraarterial chemotherapy.

STUDY DESIGN AND SETTING: 39 patients with oral and anterior oropharyngeal cancer classified N0 by [18F]FDG-PET underwent SLN scintigraphy. Selective SLN biopsy without elective neck dissection (ND) was performed, immediately followed by radical resection of the primary tumor. Histopathology included step-serial sections and immunocyto-chemistry.

RESULTS: Lymphoscintigraphy detected 104 spots. In 15 patients there was bilateral drainage. 114 SLN were excised due to additional intraoperative discrimination. 95% of visualised SLN could be removed. Histology was positive in 3 patients (8%), all underwent ND which yielded another positive node in 2 cases. Median observation time was 30 months. Two patients (5%) had a neck relapse in combination with a second primary.

CONCLUSIONS: SLN biopsy as only surgical staging tool seems to be feasible.

SIGNIFICANCE: Method promises reduction of elective ND and morbidity in N0 patients.

Intra-Operative Lymphatic Mapping and Sentinel Node Biopsy in Laryngeal Carcinoma: Preliminary Results

INTRODUCTION

Sentinel node mapping has been used for laryngeal carcinoma in several studies, with excellent results thus far. In the current study, we report our preliminary results on sentinel node mapping in laryngeal carcinoma using intra-operative peri-tumoral injection of a radiotracer.

MATERIALS AND METHODS

Patients with biopsy-proven squamous cell carcinoma of the larynx were included in the study. Two mCi/0.4 cc Tc-99m-phytate in four aliquots was injected on the day of surgery, after induction of anesthesia, in the sub-mucosal peri-tumoral location using a suspension laryngoscopy. After waiting for 10 minutes, a portable gamma probe was used to search for sentinel nodes. All patients underwent laryngectomy and modified radical bilateral neck dissection. All sentinel nodes and removed non-sentinel nodes were examined by hematoxylin and eosin (H&E) staining.

RESULTS

Ten patients with laryngeal carcinoma were included. At least one sentinel node could be detected in five patients (bilateral nodes in four patients). One patient had pathologically involved sentinel and non-sentinel nodes (no false-negative cases).

CONCLUSION

Sentinel node mapping in laryngeal carcinoma is technically feasible using an intra-operative radiotracer injection. In order to evaluate the relationship of T-stage and the laterality of the tumor with accuracy, larger studies are needed.

Current advances in diagnosis and surgical treatment of lymph node metastasis in head and neck cancer

Still today, the status of the cervical lymph nodes is the most important prognostic factor for head and neck cancer. So the individual treatment concept of the lymphatic drainage depends on the treatment of the primary tumor as well as on the presence or absence of suspect lymph nodes in the imaging diagnosis. Neck dissection may have either a therapeutic objective or a diagnostic one. The selective neck dissection is currently the method of choice for the treatment of patients with advanced head and neck cancers and clinical N0 neck. For oncologic reasons, this procedure is generally recommended with acceptable functional and aesthetic results, especially under the aspect of the mentioned staging procedure. In this review article, current aspects on pre- and posttherapeutic staging of the cervical lymph nodes are described and the indication and the necessary extent of neck dissection for head and neck cancer is discussed. Additionally the critical question is discussed if the lymph node metastasis bears an intrinsic risk of metastatic development and thus its removal in a most possible early stage plays an important role.

Implications of a positive sentinel node in oral squamous cell carcinoma

BACKGROUND

The role of sentinel node biopsy in head and neck cancer is currently being explored. Patients with positive sentinel nodes were investigated to establish if additional metastases were present in the neck, their distribution, and their impact on outcome.

METHODS

In all, 109 patients (n = 109) from 15 European centers, with cT1/2,N0 tumors, and a positive sentinel lymph node were identified. Kaplan-Meier and univariate and multivariate logistic regression analysis were used to identify variables that predicted for additional positive nodes and their position within the neck.

RESULTS

A total of 122 neck dissections were performed in 109 patients. Additional positive nodes were found in 34.4% of cases (42/122: 18 same, 21 adjacent, and 3 nonadjacent neck level). Additional nodes, especially if outside the sentinel node basin, had an impact on outcome.

CONCLUSIONS

The results are preliminary but suggest that both the number and the position of positive sentinel nodes may identify different prognostic groups that may allow further tailoring of management plans.

[Predictive ability of the CT to evaluate cervical lymph nodes in head and neck tumours]

OBJECTIVE

The aim of this study was to determine the predictive value of computed tomography (CT) i.e., its sensitivity and specificity in detecting metastatic lymph nodes of head and neck tumours. We also studied the capacity of CT in correct nodal staging.

PATIENTS AND METHODS

A CT was performed on 95 patients diagnosed with neoplastic disease of the pharynx and/or larynx. All patients subsequently underwent cervical lymph node dissections. In the imaging study, the following parameters were considered for suspected radiological nodal involvement: lymph node diameter greater than 10mm, lesion margins poorly defined, capsule enhancement after contrast administration and lymph nodes that, despite their size, had signs of central necrosis.

RESULTS

In the dissections, 70.53% resulted N+ in the histological study. The sensitivity of CT was 82.09% and the specificity, 85.71%. The CT detected positivity in 55 of the 67 histologically pathological dissections, while the CT detected negativity in 24 of the 28 dissections histologically negative. The weighted kappa index value was 0.6408, indicating limited capacity for appropriate staging of the lymph nodes.

CONCLUSIONS

While the ability of CT to detect metastatic lymph nodes in head and neck tumours is quite acceptable, it is less so for correctly staging them. It is therefore necessary to look for other imaging tests that provide greater accuracy to avoid unnecessary elective neck dissections and to reduce morbidity and mortality from them. We must now pay attention to new imaging techniques such as PET and PET/CT.

Joint practice guidelines for radionuclide lymphoscintigraphy for sentinel node localization in oral/oropharyngeal squamous cell carcinoma

Involvement of the cervical lymph nodes is the most important prognostic factor for patients with oral/oropharyngeal squamous cell carcinoma (OSCC), and the decision whether to electively treat patients with clinically negative necks remains a controversial topic. Sentinel node biopsy (SNB) provides a minimally invasive method of determining the disease status of the cervical node basin, without the need for a formal neck dissection. This technique potentially improves the accuracy of histological nodal staging and avoids over-treating three-quarters of this patient population, minimizing associated morbidity. The technique has been validated for patients with OSCC, and larger-scale studies are in progress to determine its exact role in the management of this patient population. This article was designed to outline the current best practice guidelines for the provision of SNB in patients with early-stage OSCC, and to provide a framework for the currently evolving recommendations for its use. These guidelines were prepared by a multidisciplinary surgical/nuclear medicine/pathology expert panel under the joint auspices of the European Association of Nuclear Medicine (EANM) Oncology Committee and the Sentinel European Node Trial Committee.

Sentinel lymph node biopsy accurately stages the regional lymph nodes for T1-T2 oral squamous cell carcinomas: results of a prospective multi-institutional trial

PURPOSE

The validity of sentinel lymph node biopsy (SLNB) for T1 or T2, clinically N0, oral cancer was tested by correlation of sentinel node pathologic status with that of nodes within the completion neck dissection.

METHODS

This prospective, cooperative group trial involved 25 institutions over a 3-year period. One hundred forty patients with invasive oral cancers, stage T1 and T2, N0 including 95 cancers of the tongue, 26 of the floor of mouth, and 19 other oral cancers were studied. The study excluded lesions with diameter smaller than 6 mm or minimal invasion. Imaging was used to exclude nonpalpable gross nodal disease. Patients underwent injection of the lesion with (99m)Tc-sulfur colloid, nuclear imaging, narrow-exposure SLNB, and completion selective neck dissection. The major end point was the negative-predictive value (NPV) of SLNB.

RESULTS

In the 106 SLNBs, which were found to be pathologically and clinically node-negative by routine hematoxylin and eosin stain, 100 patients were found to have no other pathologically positive nodes, corresponding to a NPV of 94%. With additional sectioning and immunohistochemistry, NPV was improved to 96%. In the forty patients with proven cervical metastases, the true-positive rate was 90.2% and was superior for tongue tumors relative to floor of mouth. For T1 lesions, metastases were correctly identified in 100%.

CONCLUSION

For T1 or T2 N0 oral squamous cell carcinoma, SLNB with step sectioning and immunohistochemistry, performed by surgeons of mixed experience levels, correctly predicted a pathologically negative neck in 96% of patients (NPV, 96%).

Rap1 stabilizes beta-catenin and enhances beta-catenin-dependent transcription and invasion in squamous cell carcinoma of the head and neck

PURPOSE

In head and neck squamous cell carcinoma (HNSCC) cells, Rap1 shuttles between the nucleus and cytoplasm. Prior findings suggested that Rap1 may modulate the beta-catenin-independent Wnt pathway in some settings, but the role of Rap1 in beta-catenin-dependent Wnt signaling remains undefined.

EXPERIMENTAL DESIGN AND RESULTS

We observed that beta-catenin bound to active Rap1 in vitro and Rap1 activated beta-catenin/T-cell factor (TCF)-dependent transcription. Immunofluorescence studies showed that ectopic expression of Rap1 increased nuclear translocation of beta-catenin. Overexpression of active Rap1 facilitated an increase in beta-catenin-mediated transcription that was abrogated by dominant-negative TCF4. Conversely, small interfering RNA-mediated inhibition of endogenous Rap1 expression inhibited beta-catenin/TCF-mediated transcription as well as invasion of HNSCC. Furthermore, inhibition of Rap1 expression downregulated the expression of matrix metalloproteinase 7, a transcriptional target of beta-catenin/TCF. In HNSCC cells stably transfected with beta-catenin or treated with lithium chloride or Wnt3A to stabilize endogenous beta-catenin, inhibition of Rap1 expression led to decreases in the free pool of beta-catenin. Immunohistochemical studies of tissue from HNSCC patients revealed that increased beta-catenin intensity correlated with higher tumor stage. Furthermore, the prognostic effect of active Rap1 on tumor N stage was found to depend on cytosolic beta-catenin expression (P < 0.013). When beta-catenin is high, higher Rap1GTP intensity is associated with more advanced N stage.

CONCLUSIONS

The findings suggest that Rap1 enhances beta-catenin stability and nuclear localization. In addition to indicating that Rap1 has a significant role in regulating beta-catenin and beta-catenin-dependent progression to more advanced N-stage lesions, these data highlight Rap1 as a potential therapeutic target in HNSCC.

Joint Practice Guidelines for Radionuclide Lymphoscintigraphy for Sentinel Node Localization in Oral/Oropharyngeal Squamous Cell Carcinoma

Involvement of the cervical lymph nodes is the most important prognostic factor for patients with oral/oropharyngeal squamous cell carcinoma (OSCC), and the decision of whether to electively treat patients with clinically negative necks remains a controversial topic. Sentinel node biopsy (SNB) provides a minimally invasive method for determining the disease status of the cervical node basin, without the need for a formal neck dissection. This technique potentially improves the accuracy of histologic nodal staging and avoids overtreating three-quarters of this patient population, minimizing associated morbidity. The technique has been validated for patients with OSCC, and larger-scale studies are in progress to determine its exact role in the management of this patient population. This document is designed to outline the current best practice guidelines for the provision of SNB in patients with early-stage OSCC, and to provide a framework for the currently evolving recommendations for its use. Preparation of this guideline was carried out by a multidisciplinary surgical/nuclear medicine/pathology expert panel under the joint auspices of the European Association of Nuclear Medicine (EANM) Oncology Committee and the Sentinel European Node Trial (SENT) Committee.

Lymphosonographic sentinel node biopsy of the supraglottis in a swine model

OBJECTIVE

To test the feasibility of a novel contrast-enhanced ultrasound (CEUS) technique, or lymphosonography, for sentinel node biopsy (SNB) of the supraglottis in a porcine model.

STUDY DESIGN AND SETTING

In this prospective, nonrandomized animal study, blue dye and ultrasound contrast agent were injected into the supraglottis in seven 50-kg Yorkshire swine. Transcutaneous CEUS was used to identify real-time lymphatic flow of contrast through lymph channels (LC) to the sentinel lymph node (SLN). SNB was carried out, visually identifying a blue node, with the assistance of intraoperative CEUS. Bilateral modified radical neck dissections were performed to search for any residual contrast-positive or blue SLNs.

RESULTS

In each case, at least one SLN was identified by preoperative CEUS. A total of 12 nodes were identified on preoperative CEUS, and 11 of 12 nodes were stained with blue dye (91.7%). No residual blue or contrast-positive nodes were identified on neck dissection.

CONCLUSIONS

Lymphosonographic SNB of the supraglottis in a porcine model is technically feasible, and yields results comparable to traditional blue dye-guided techniques. No "shine-through" effect or nonsequential nodal enhancement occurred. This technique holds promise for sentinel node biopsy and allows a novel method for in vivo investigation of the lymphatic system.

Efficacy of diagnostic upper-node procedures during laryngectomy for glottic carcinoma

BACKGROUND

Regional recurrence of glottic squamous cell carcinoma was evaluated in patients with a clinically N0 neck who underwent selective upper-node dissection (SUND) or selective upper-node inspection (SUNI; surgical visualization and palpation of jugular lymph nodes at levels II and III) during (salvage) laryngectomy.

METHODS

In 152 patients, 291 clinically N0 (139 bilateral and 13 contralateral) necks were evaluated for occult neck metastases by SUNI or SUND during (salvage) laryngectomy.

RESULTS

Occult neck metastases were identified with SUNI or SUND in 7% of the necks (21 of 291). In 4% (n = 11) of the remaining 270 necks, regional recurrence was detected during follow-up evaluation. Thus, in these 8 patients, SUNI or SUND seemed to have failed.

CONCLUSIONS

SUND or SUNI of levels II and III during (salvage) laryngectomy identified the vast majority of patients who needed extensive neck treatment. In the N0 necks, these techniques led to less morbidity than elective neck dissection.

Sentinel node concept in clinically n0 laryngeal and hypopharyngeal cancer

BACKGROUND

Sentinel nodes (SNs) are the lymph nodes that directly receive lymphatic flow from a primary cancer lesion. The SN concept implies that lymphatic metastasis initially occurs at SNs. SN navigation surgery can be introduced for cancers in which the SN concept is established. In SN navigation surgery, lymph node dissection beyond SNs can be omitted if SNs are metastasis free. Although the SN concept has been investigated frequently for oral and oropharyngeal cancer, it has so far been investigated less for laryngeal and hypopharyngeal cancer. In this study, we investigated whether the SN concept is applicable for laryngeal and hypopharyngeal cancer.

METHODS

Twenty patients with T2-T4 and clinically N0 laryngeal and hypopharyngeal cancer were recruited. (99m)Tc-phytate was injected into several sites surrounding the tumor on the day before surgery. Lymphoscintigrams were acquired from at least two different viewpoints. SNs were surveyed intraoperatively, and neck dissections including at least levels II, III, and IV were performed.

RESULTS

SNs had occult metastases in five cases. In the remaining 15 cases, neither SNs nor other lymph nodes contained metastases, consistent with the SN concept. There was one false-negative case showing delayed nodal metastasis 2 years after initial surgery. The overall accuracy of the SN concept was 95%.

CONCLUSION

Our study shows that SN biopsy is a reliable strategy to determine correct lymph node status in N0 laryngeal and hypopharyngeal cancer. SN detection was valuable in evaluating the need for neck dissection, whether ipsilaterally or bilaterally.

The diagnostic role of radioactivity in sentinel nodes in oral and oropharyngeal cancer

Sentinel lymph node biopsy (SNB), using radioactive tracers, is a novel, interesting tool in the staging of patients with oral and oropharyngeal squamous-cell carcinoma (OOSCC), which could lead to a reduced rate of elective neck dissections. The aim of the study was to evaluate the ranking of measured radioactivity in the sentinel lymph nodes (SLNs) and to correlate these findings with histopathological results to assess the number of SLN being sufficient for exact staging of the neck. In 77 consecutive patients with T1-4 OOSCC clinically and positron emission tomography-staged N0, between 15 and 55 MBq of Tc- 99m-labeled albumin-microcolloids were injected peritumorally and 213 SLNs were excised by small skin incisions using a gamma probe 2-3 hours later. The counts per second (cps) were measured ex vivo and excised SLNs were ranked according to their cps defining the LN with the highest activity as primary SLN, followed by a 2nd, 3rd, and so forth, SLN. Elective neck dissections were not performed. Median activity was 213 cps. All levels harbored SLNs with a maximum (43%) in level II and a minimum in level V (1%). SLNs in level II had significantly higher tracer accumulation (median, 289 cps) than those in levels I (144 cps) and IV (149 cps), but distant levels did not have significantly lower counts, compared to proximal. Eight (8) pathologically positive SLNs in 7 patients (7/77 = 9%; median activity, 157 cps) were detected. The median counts of the positive SLNs were not significantly different from those of the 205 negative SLNs (235 cps). The positive SLN was the one with the highest tracer accumulation in 4 cases, with the second highest in 1 case, and with the third highest tracer accumulation in 2 cases. Three (3) positive SLN were in level IB, 4 in level IIA, and 1 in level III. One (1) patient had 2 positive SLNs: a SLN with the third highest activity in level IIB and a SLN with the fifth highest activity in level III. In OOSCC, excision of only 1 SLN is not feasible. The positive SLNs were not necessarily the hottest nodes. Utilizing radiotracer lymphatic mapping, the 3 SLNs with the highest activity should be excised for exact staging of the neck in patients with T1-3 tumors. Excision of all radioactive nodes is recommended until further studies will prove this result. Large T4a tumors should not be staged using SNB.

Head and Neck Squamous Cell Carcinoma: Sentinel Node or Selective Neck Dissection

Improved knowledge about the metastatic behavior of mucosal squamous cell cancer of the head and neck made it possible to reduce the extension of elective and even therapeutic neck dissections by sparing selected levels, thereby reducing morbidity. The diagnostic question of when to treat a clinically negative neck to avoid unnecessary overtreatment, even through selective neck dissections, might be answered with sentinel lymph node biopsy. A thorough and sophisticated evaluation of this technique is necessary when defining suited patients.

The role of SPECT-CT in the lymphoscintigraphic identification of sentinel nodes in patients with oral cancer

CONCLUSION

SPECT-CT may improve the localization of sentinel nodes (SNs) in patients with oral squamous cell carcinoma (OSCC). Compared with planar lymphoscintigraphy SPECT-CT detected more SNs and provided additional anatomical and spatial information about their localization. New generation SPECT with higher resolution CT scanners are expected to provide more accurate information about the localization of SNs.

OBJECTIVE

To assess the role of combined SPECT-CT in SN identification in the clinically negative neck of patients with OSCC.

MATERIALS AND METHODS

Lymphoscintigraphy comprising planar and SPECT-CT acquisition was performed in 34 consecutive patients with OSCC stage I and II (T1-2N0M0) prior to sentinel node biopsy (SNB) and selective neck dissection. The number of SNs and anatomical location was recorded according to lymphoscintigraphy and operative findings.

RESULTS

SNB was conducted in 33 patients. SNs were identified in 94% (32/34) of the patients using SPECT-CT. In 91% (29/32) of the patients SNs were harvested from all of the levels involved on SPECT-CT. SPECT-CT imaging demonstrated extra SNs compared with planar lymphoscintigraphic imaging in 47% (15/32) of patients. In seven cases the anatomical level of SN according to SPECT-CT was reclassified during surgery. The overall incidence of lymph node metastases was 19% (6/32). There were no false negative SNs.

Radiolocalized Sentinel Lymph Node Biopsy in Squamous Cell Carcinoma of the Oral Cavity and Analysis of Various Parameters

BACKGROUND

Sentinel lymph node (SLN) biopsy seems to be a method that solves the problem of neck management with oral squamous cell carcinoma. Using blue dye methods for detection of neck SLNs from the surface of the operative field seems difficult; therefore, we used radiolocalization alone to detect and extract sentinel nodes. Aside from the various histological and clinical parameters examined in this procedure, we also determined whether they had any clinical significance in relation to the detection of SLNs during the operation.

METHODS

Enrolled subjects had preoperative clinical N0 stage squamous cell carcinoma of the oral cavity and had received an unfiltered (99m)Tc sulfur colloid peritumoral injection. Localization of the SLNs was performed by using lymphoscintigraphy and a handheld gamma probe.

RESULTS

In total, 28 oral squamous cell carcinoma patients were included in this prospective study. Sixty-four SLNs in 27 patients were identified by this method. The identification rate was 96.4%. No false-negative predictions of SLN were noted among any of the patients studied. The numbers of the SLNs found during the operation were larger in patients with positive findings than those with negative findings (P < .05 by the Mann-Whitney U-test).

CONCLUSIONS

SLN radiolocalization provided an acceptable identification rate. The cases of positive findings for metastasis seemed to statistically have more SLNs than did those with negative findings, but more evidence is needed to prove this point. Therefore, SLN biopsies for extracting all possible high-risk nodes may be conducive for oral squamous cell carcinoma surgery.

El ganglio centinela en tumores de laringe: técnica y resultados obtenidos

OBJECTIVES

To evaluate the applicability of sentinel node biopsy in NO carcinomas of the larynx.

MATERIALS AND METHODS

We carried out a prospective study in 19 patients with carcinoma of the larynx NO. We peritumorally infiltrate with 1 mCi 99mTc-labeled nanocolloidal albumin via rigid endoscopy in general anaesthesia. Sentinel node detection is performed with a gamma sonda during lymph node detection. The histological results of the sentinel node are compared with the excised neck dissection specimen.

RESULTS

Identification of sentinel node was successful in 17 patients (89.47%). In 11 patients the sentinel node was tumor negative reflecting the correct neck lymph node status (pNO). Three patients had metastases in the sentinel node. We observed three false- negative. The sensitivity of the technique was 50% (3/6) and the negative predictive value 78.6%.

CONCLUSIONS

We think that more studies are needed to use the technique in the laryngeal cancer and that a correct selection of the patients is essential.

Sentinel node biopsy and head and neck tumors—Where do we stand today?

BACKGROUND

Sentinel lymph node sampling may be studied profitably in series of patients with 1 tumor type, such as breast carcinoma, in 1 anatomic locale. The present work analyzes the efficacy of sentinel node sampling in a pathologically diverse group of lesions from an anatomically diverse region such as the head and neck; however, there are risks conflating the findings in different tumors with radically different behaviors, in the process producing muddled data. This report reviews the head and neck experience with sentinel sampling and concludes that certain tumor types that have a known propensity for aggressive behavior are the best candidates for trials employing sentinel node sampling; candidates include many cutaneous melanomas of the head and neck, oropharyngeal squamous carcinomas, and selected thyroid carcinomas. Despite the growing popularity of sentinel node sampling in a variety of regions of the body, however, at this juncture this technique remains an investigational procedure, pending demonstration of a tangible improvement in patient outcome through its use. It is recommended that studies of the efficacy of this technique strive, whenever possible, to segregate results of different tumor types in different head and neck locales from one another so as to produce more focused findings for discrete types of malignancies, and not group together tumor types that may in reality exhibit different biological behaviors.

Reduced Cisplatin Sensitivity of Head and Neck Squamous Cell Carcinoma Cell Lines Correlates with Mutations Affecting the COOH-Terminal Nuclear Localization Signal of p53

PURPOSE

Head and neck squamous cell carcinomas (HNSCC) are the most frequent malignancies of the upper aerodigestive tract. Cisplatin resistance is a major problem in the treatment of a large number of HNSCC cancer patients. In this study, nine randomly selected HNSCC cell lines were investigated regarding expression, presence of mutations, nucleocytoplasmic distribution of p53, and sensitivity to cisplatin.

EXPERIMENTAL DESIGN

Protein expression was evaluated by Western blot analysis. The whole open reading frame of p53 was determined by reverse transcription-PCR sequencing. Nucleocytoplasmic distribution was evaluated by confocal laser scanning microscopy. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide viability assay was used to test for cisplatin sensitivity.

RESULTS

p53 mutations were found in all nine investigated HNSCC cell lines. Nuclear p53 signal was detected in six cell lines, whereas three cell lines exhibited total loss of nuclear p53 signal. Nuclear signal depended on the presence or absence of the COOH-terminal nuclear localization signal in p53. Cisplatin sensitivity was highly reduced in the group with loss of nuclear p53 signal compared with those with detectable nuclear signal. Transfection of wild-type and mutant p53 into a rat embryonic cell system showed highly reduced activity of the nuclear localization signal mutant p53 protein.

CONCLUSION

Taken together, these data suggest that "loss of nuclear p53 signal" correlates with cisplatin resistance in HNSCC. If these results can be validated on a larger number of tumor samples, including fresh tumor tissues, it potentially could help in sparing a subgroup of HNSCC patients the side effects associated with unnecessary chemotherapy by identifying cisplatin nonresponders before chemotherapy induction.

Sentinel Node Localization in Head and Neck Tumors

Sentinel lymph node biopsy (SLNB) is a minimally invasive method that was developed to stage the regional lymphatics of patients with cutaneous melanoma. Many studies performed worldwide have shown that SLNB is a feasible method to stage the cervical lymphatics in patients with head and neck squamous cell carcinoma (HNSCC). The accuracy of SLNB in patients with HNSCC is currently under investigation in a multicenter study sponsored by the American College of Surgeons Oncology Group that compares the results of SLNB with standard elective neck dissection. Research to date has also shown that multiple SLNs and individualized drainage patterns characterize head and neck mucosal sites. These findings suggest that lymphoscintigraphy alone may be useful to delineate the lymphatic basins that require treatment in patients with HNSCC and in patients whose head and neck lymphatics are disrupted because of prior surgery or irradiation.

Role of sentinel node biopsy in the management and staging of the N0 neck

Sentinel node biopsy is being increasingly used as a staging tool for mucosal head and neck cancer. This review of the literature summarizes the results of research into the procedure when it has been performed in three main contexts: as part of an ipsilateral neck dissection, as a stand-alone procedure to stage the neck for positive or negative disease, and as a means of investigating the non-involved or contralateral neck in tumors close to or crossing the midline. The role of the procedure is discussed and the difficulties encountered are expanded, with a particular emphasis on pitfalls of the technique, caveats, and its potential role for the future.

Sentinel-Lymphonodektomie als Staging-Methode bei Kopf-Hals-Karzinomen

BACKGROUND

The excision of sentinel lymph nodes has a growing relevance in the diagnosis of oral and oropharyngeal cancer in cases of N0 necks. The validity of sentinel node biopsy (SNB) was examined as a single surgical staging tool.

PATIENTS AND METHODS

Within the framework of a multi-modal treatment scheme, SNB without elective neck dissection was carried out on 70 previously untreated patients in the same session as the surgery for the primary cancer. Control of accuracy was via observation of the manifestation of neck node metastases in 45 patients who were postoperatively irradiated.

RESULTS

A total of 94% of sentinel nodes could be excised; 9 patients (13%) had positive nodes and were treated with a therapeutic neck dissection (ND). There were 2 neck node metastases as second primaries, all other patients remained regionally inconspicuous (median observation time 26 months).

CONCLUSION

As a staging tool for N0 necks and T1-3 tumors, SNB could lead to a considerable reduction in the number of elective NDs. It could be well integrated into a multi-modal treatment scheme.

Intraoperative lymphatic mapping in cases of midline squamous cell carcinoma

OBJECTIVE

To analyze the value of intraoperative lymphatic mapping in cases of midline primary head and neck squamous cell carcinoma (HNSCC) in clinically staged N0 necks.

MATERIAL AND METHODS

Eleven patients with HNSCC of the epiglottis (2 T1, 6 T2, 3 T3), all of whom were staged with a neck status of N0 using sonography and CT, underwent intraoperative peritumoral (99m)Tc-nanocoll injection (4 sites; 45 MBq), radiolabeled detection and analysis of up to 3 hot sentinel nodes (SNs) during elective neck dissection.

RESULTS

Gamma probe use revealed bi- and unilateral intranodal tracer uptake in 6/11 and 5/11 patients, respectively. In 2/6 patients with bilateral intranodal tracer uptake an SN with an isolated metastasis was found at one neck site while the other four patients were tumor-free in the SNs. Of the five patients with unilateral intranodal tracer uptake, three had radiolabeled SNs containing isolated metastases whereas two had no cancer detected, giving a total occult cancer rate of 45% (5/11). No cancer was found in non-labeled nodes.

CONCLUSIONS

Intraoperative lymphatic mapping correctly identified the stage of metastatic disease. Unilateral tracer uptake represented the pathway of occult metastatic spread in 3/5 patients and the disease-free neck status of both neck sites in 2/5 patients. No patient had occult bilateral cancer. Future investigations should be done to determine whether intraoperative lymphoscintigraphy can guide the indication for unilateral only or bilateral neck dissection in these patients.

Pattern of drainage in sentinel lymph nodes after intra-arterial chemotherapy for oral and oropharyngeal cancer

PURPOSE

Prerequisite for lymphoscintigraphy-guided sentinel lymph node (SLN) biopsy in head and neck cancer patients has been a previously untreated primary tumor to avoid disturbance of the lymphatic flow. We evaluated the feasibility in a multimodality treatment approach to oral and oropharyngeal cancer comprising presurgical intra-arterial chemotherapy of the primary tumor.

PATIENTS AND METHODS

In a prospective study of 35 consecutive patients with primary oral and anterior oropharyngeal cancer T1-4N0 treated with superselective intra-arterial chemotherapy with high-dose cisplatin, SLN scintigraphy was performed on the day of surgery, including gamma camera imaging before and hand-held gamma probe identification of the SLN during surgery. SLN biopsy was performed in 50 neck sides, followed by radical resection of the primary in the same session. Elective neck dissection was not carried out. The pattern of lymphatic drainage was recorded and compared with the literature on well-known patterns found in lymphographic studies and metastatic disease in neck dissection specimens of patients without presurgical treatment.

RESULTS

Drainage patterns of SLN related to different primary locations mapped the mentioned comparison patterns. SLN drainage patterns gave strong evidence that there are SLN in levels 3 and 4 with direct drainage from the primary. After a median observation time of 24 months, no patients had a neck relapse.

CONCLUSIONS

The results suggest that intra-arterial chemotherapy of the primary tumor does not significantly alter lymphatic drainage and that SLN biopsy following intra-arterial chemotherapy is feasible and offers valid results comparable to those obtained from patients without presurgical treatment.

Multimodal image registration for localization of sentinel nodes in head and neck squamous cell carcinoma

PURPOSE

The aim of this clinical study was to propose a new method of preoperative 3-dimensional localization of the neck sentinel node in clinically and radiographically N0 squamous cell carcinoma of the oral cavity.

PATIENTS AND METHODS

This prospective study was carried out between August 2002 and August 2003. Ten patients with staged oral squamous cell cancer underwent this method of preoperative localization of the sentinel lymph node. At the present time, lymphoscintigraphy is recognized as the investigation of choice for the preoperative detection of sentinel nodes. Although we found it to be highly sensitive (100% in our study), it does not allow precise localization of the sentinel node in the anatomic context of the neck. To overcome this drawback, we used multimodal image registration applied to the cervical region in association with the imaging modalities of scintigraphy (single-photon emission computed tomography [SPECT] and gamma transmission) and computed tomography (CT). SPECT and gamma transmission (barium-133 sources) were carried out with a triple-head Philips-Marconi camera (Philips Medical System, Cleveland, OH), and CT was carried out with a General Electric console (GE Medical Systems, Milwaukee, WI). Gamma transmission was used to place the SPECT images in a reference cervical anatomic context (CT images). Registration involved the use of a manual method based on definition of homologous volume structures.

RESULTS

Preoperative image registration effectively localized the cervical sentinel node in 9 of the 10 patients, enabling a guided surgical approach in 90% of cases. The sentinel node was localized and resected using a hand-held gamma probe.

CONCLUSIONS

This original study adapts a new tool (multimodal image registration) to obtain precise preoperative localization of the cervical sentinel node in N0 oral squamous cell carcinoma. We confirmed the feasibility of this method in this indication. Although this method is a novel one, we believe that it will become extremely useful once a consensus has been reached on exclusive excision of the cervical sentinel node in oral cancers, as is the case for melanoma or breast cancer.

Sentinel node biopsy in squamous cell cancer of the oral cavity and oral pharynx: A diagnostic meta-analysis

BACKGROUND

The sentinel node biopsy concept has been gaining support in the head and neck cancer literature during only the last few years, and several pilot studies have been published. This procedure aims to avoid unnecessary treatment to the clinically negative neck by identifying the patients with occult neck disease.

METHODS

We performed a systematic review and a diagnostic meta-analysis of all published literature regarding sentinel node biopsies in head and neck cancer until December 2003 using established guidelines. Using the pooled sensitivity rates obtained from the meta-analysis and treatment outcomes from published literature, we created a decision analysis model to identify the treatment arm with better payoffs.

RESULTS

A total of 301 patients with oral cavity primary tumors and 46 patients with oropharyngeal primary tumors from 19 articles were included for the meta-analysis. The pooled sensitivity result using the random effects model was 0.926 (95% confidence interval, 0.852-0.964). The cumulative payoff for the sentinel node biopsy arm was lower than that for the elective node dissection arm by about 1%. The payoffs were assigned for the recurrence and mortality rates only and did not take into account the morbidity caused by the procedures.

CONCLUSIONS

The sentinel node biopsy procedure has shown high sensitivity rates in pilot studies for oral and oropharyngeal squamous cell cancer across the globe and is reliable and reproducible. This study provides a firm evidence base for forthcoming trials on the role of sentinel node biopsy in head and neck cancer.

Histopathologic validation of the sentinel node concept in oral and oropharyngeal squamous cell carcinoma

BACKGROUND

In patients with head and neck squamous cell carcinoma (HNSCC), the presence of lymph node metastases is the most important prognosticator. Sentinel node (SN) biopsy has been shown to be an accurate staging technique for patients with breast cancer and melanoma and might also be suited for patients with HNSCC. This study was undertaken to determine whether the SN concept holds true for HNSCC and could be exploited for SN biopsy.

METHODS

In 22 patients with T2 to T4 N0 oral or oropharyngeal squamous cell carcinoma (SCC) who were scheduled to undergo combined primary tumor excision and elective unilateral (n = 17) or bilateral (n = 5) neck dissection, SN identification was performed the day before surgery by use of lymphoscintigraphy after peritumoral injections of 99mTc-labeled colloidal albumin. After the neck dissection specimens were removed, all SNs, all other radioactive lymph nodes, and all nonradioactive lymph nodes were retrieved for histopathologic analysis, including serial sectioning at 250-microm intervals and immunohistochemical analysis (IHC).

RESULTS

Overall, in 21 (78%) of 27 neck sides, an SN was identified by scintigraphy. Of the six neck sides in which SNs were not identified by scintigraphy, four were from three patients who underwent bilateral neck dissection. In another patient treated by bilateral neck dissection, the SN identified by scintigraphy could not be found in the specimen. In the remaining 20 neck dissection specimens, 23 SNs and 30 additional radioactive lymph nodes could be found. At histologic examination of the 20 neck specimens in which the SN was found, at least one SN was tumor positive in eight cases. In one neck specimen, a metastasis was detected in a nonradioactive lymph node, whereas the SN was tumor free, also at serial sectioning and IHC. In the remaining 11 neck sides in which the SN was tumor negative, none of the other radioactive (n = 13) and none of the nonradioactive (n = 279) lymph nodes contained tumor at histopathologic analysis, including serial sectioning and IHC. The sensitivity of the SN procedure for predicting lymph node metastases, therefore, was 89% (eight of nine neck specimens) when an SN was identified by scintigraphy and found in the specimen. The overall accuracy of the SN procedure for predicting the presence or absence of lymph node metastases in the neck was 95% (19 of 20 neck specimens).

CONCLUSIONS

Our study seems to validate the SN hypothesis for oral and oropharyngeal cancer. The role of SN biopsy in the management of the N0 neck in such patients has yet to be established through prospective trials. SN identification (and thus biopsy) does not seem to be reliable in patients with tumors located in or close to the midline.