The value of frozen section analysis of the sentinel lymph node in clinically N0 squamous cell carcinoma of the oral cavity and oropharynx

Oral Cavity Cancer Surgical and Nodal Management: A Review From the American Head and Neck Society

Importance

Lymph node metastases from oral cavity cancers are seen frequently, and there is still inconsistency, and occasional controversies, regarding the surgical management of the neck in patients with oral cancer. This review is intended to offer a surgically focused discussion of the current recommendations regarding management of the neck, focusing on the indications and extent of dissection required in patients with oral cavity squamous cell carcinoma while balancing surgical risk and oncologic outcome.

Observations

The surgical management of the neck for oral cavity cancer has been robustly studied, as evidenced by substantial existing literature surrounding the topic. Prior published investigations have provided a sound foundation on which data-driven treatment algorithms can generally be recommended.

Conclusions

Existing literature suggests that patients with oral cavity cancer should be fully staged preoperatively, and most patients should receive a neck dissection even when clinically N0. Quality standards supported by the literature include separation of each level during specimen handling and lymph node yield of 18 or more nodes. Sentinel lymph node biopsy can be considered in select tumors and within a well-trained multidisciplinary team.

A retrospective analysis of 5-year post surgery recurrence of N0 neck and the role of methylene blue in sentinel lymph node biopsy

The aim of this study is to perform a retrospective analysis of the feasibility of the clinical application of SLNB using methylene blue dye (MBD) for the identification of SLN followed by frozen section biopsy to detect occult metastasis in clinically N0 necks. Hence, to know the reliability of MBD in reducing the need for extensive surgery.

Methods

We retrospectively analyzed the clinic pathological data of 48 patients with early oral cancer.The SLN identification rate (IR) was calculated in SLNB with MBD and the false-negative rate (FNR). Intra operative frozen section biopsy was done for all patients was compared with post-operative paraffin histopathology report and the prognosis of patients was analyzed.

Results

Analysis of the 48 SLNB cases showed that there were significant differences in SLN successful detection rate among patients with different site (p = 0.043) and clinical presentation (p = 0.007). Similar significant results (p < 0.05) were observed with intra-operative frozen and post-operative paraffin histopathology sections. SLNs were successfully detected in 37(77.1%) patients out of 48. The intra operative frozen histopathology completely matched with the post-operative paraffin histopathology showing 39 (81.2%) negative and 09 (18.8%) positive cases. A prognostic analysis of SLN detection based on 48 patients showed that the 5-year survival rate was 100%.

Conclusion

MBD has acceptable SLN identification rate and a low FNR(false negative report) in frozen sections. Stained SLNs with no SLN metastasis are associated with disease-free survival (DFS). Hence, MBD-SLN biopsy has significantly reduced the need for extensive neck dissection in N0 neck with less morbidity.

Comparison of intraoperative imprints cytology with frozen section for lymph node metastasis in patients with head and neck squamous cell carcinoma

BACKGROUND

Intraoperative evaluation of lymph nodal metastasis in head and neck squamous cell carcinoma (HNSCC) assumes importance and avoids over-treatment in clinically node negative (N0) neck. Frozen section (FZ) is the commonly employed technique, but it requires significant investment in resources, time, and personnel. Intraoperative imprint cytology (IC) is a rapid, reliable, and inexpensive alternative. We conducted a prospective study to assess the diagnostic accuracy of intraoperative IC and FZ for lymph node metastasis in HNSCC.

METHODS

All patients presenting with HNSCC with clinically N0 neck undergoing surgery were included in the study, and intraoperative assessment of clinically suspicious nodes was done using IC and FZ and was reviewed by two independent pathologists. The sensitivity, specificity, and accuracy of IC and FZ were calculated with reference to the final histopathology report. The time duration for reporting was calculated.

RESULTS

Thirty-four patients with clinically N0 neck were included in the study, and 85 slides were examined. The sensitivity, specificity, and accuracy of FZ were 100%, 98.6%, and 98.9%, respectively, whereas for IC, it was 85.7%, 95.8%, and 94.1%, respectively. The mean time duration for reporting for FZ and IC was 41.18 ± 3.62 and 18.12 ± 2.01 minutes, respectively.

CONCLUSION

IC provides a cheaper, accurate, and rapid alternative for FZ for intraoperative assessment of neck nodes in HNSCC, and it assumes importance in resource-driven countries like India.

Clinicopathological study of involvement of the submandibular gland in oral squamous cell carcinoma

Our purpose was to provide a pathological basis for preservation of the submandibular glands during neck dissection for oral squamous cell carcinoma (SCC) by investigating whether intraglandular lymph nodes exist in submandibular glands, and the modes of involvement of submandibular glands in oral SCC. We studied the records of 95 patients with oral SCC (other than that in the floor of the mouth) treated at our hospital from January 2017 to June 2018. The specimens of submandibular glands discarded after neck dissection were analysed, and serially sectioned. Sections 5μm thick were obtained at 0.5mm intervals and stained with haematoxylin and eosin for examination under light microscopy. A total of 116 specimens were obtained from the 95 patients, and about 5000 slides were evaluated. No intraglandular lymph nodes were detected in the submandibular glands. In the subgroup of patients whose primary tumours had extended into the floor of the mouth, four submandibular glands were involved by direct spread of the primary tumour. In the subgroup with metastases to level Ib lymph nodes, four submandibular glands were involved by extranodal extension from the metastatic nodes. No intraglandular lymph nodes or micrometastases were detected. We conclude that no intraglandular lymph nodes are present in submandibular glands, which may be involved by direct extension of the primary carcinoma or metastatic cervical lymph nodes with extranodal extension. Preservation of the submandibular glands during neck dissection seems to be feasible and safe in selected patients with oral SCC.

Exploring the Role of Intraoperative Frozen Section of the Sentinel Lymph Node in the Management of Early-Staged Oral Tongue Cancers

Background:

The present study aims to explore the role of sentinel lymph node biopsy (SLNB) with intraoperative frozen section in the management of early-staged oral tongue cancers.

Materials and Methods:

Fifty-two patients with clinical stages cT1/2N0 oral tongue cancers were included in the present study. The curative surgery was preceded by the performance of an SLNB using a dual technique.

Results:

The identification rate of sentinel lymph node (SLN) in this study was 98.07%. The sensitivity, specificity, positive predictive value (PPV), and the negative predictive value (NPV) of SLNB were 88.2%, 100%, 100%, and 94.5%, respectively. Further, the sensitivity, specificity, PPV, and the NPV of intraoperative frozen section of the SLN were 70.5%, 100%, 100%, and 87.5%, respectively.

Conclusions:

The addition of intraoperative frozen section could identify 70.5% of patients with occult metastasis. An intraoperative frozen section assessment of sentinel node has the potential to change the overall management of patients with early-oral tongue cancers.

Intraoperative Sentinel Lymph Node Evaluation: Implications of Cytokeratin 19 Expression for the Adoption of OSNA in Oral Squamous Cell Carcinoma

BACKGROUND

Intraoperative analysis of sentinel lymph nodes would enhance the care of early-stage oral squamous cell carcinoma (OSCC). We determined the frequency and extent of cytokeratin 19 (CK19) expression in OSCC primary tumours and surrounding tissues to explore the feasibility of a "clinic-ready" intraoperative diagnostic test (one step nucleic acid amplification-OSNA, sysmex).

METHODS

Two cohorts were assembled: cohort 1, OSCC with stage and site that closely match cases suitable for sentinel lymph node biopsy (SLNB); cohort 2, HNSCC with sufficient fresh tumour tissue available for the OSNA assay (>50 mg). CK19 assays included qRT-PCR, RNA in situ hybridisation (ISH), and immunohistochemistry (IHC), as well as OSNA.

RESULTS

CK19 mRNA expression was detected with variable sensitivity, depending on method, in 60-80% of primary OSCC tumours, while protein expression was observed in only 50% of tumours. Discordance between different techniques indicated that OSNA was more sensitive than qRT-PCR or RNA-ISH, which in turn were more sensitive than IHC. OSNA results showed CK19 expression in 80% of primary cases, so if used for diagnosis of lymph node metastasis would lead to a false-negative result in 20% of patients with cervical lymph node metastases.

CONCLUSIONS

OSNA in its current form is not suitable for use in OSCC SLNB due to inadequate expression of the CK19 target in all case. However, the same assay technology would likely be very promising if applied using a more ubiquitous squamous epithelial target.

Feasibility of Endoscopic Sentinel Node Biopsy in the Porcine Neck

OBJECTIVE: To assess the feasibility of endoscopic sentinel node biopsy (SNB) using a tracer dye in a pig model.

STUDY DESIGN AND SETTING: This was a prospective, nonrandomized experimental study in Yorkshire pigs. The posterolateral tongues of three animals were injected with a one-to-one solution of carbon dye to methylene blue dye. Endoscopic SNB was performed and stained lymph nodes identified and retrieved, followed by an open dissection to recover any remaining nodes. Specimens were analyzed by a pathologist for staining, size, and structural integrity.

RESULTS: Six unilateral endoscopic SNBs were performed without complications. During endoscopic dissection, gross blue-staining of a sentinel node was noted in four of six dissections (66%). One of six sentinel nodes demonstrated histologic evidence of carbon staining. Structural integrity of all nodes was intact upon histological evaluation.

CONCLUSION/SIGNIFICANCE: Endoscopic cervical SNB in pigs is feasible but has limitations based on lymph node size and reliability of tracer dyes. Further study is warranted to perfect tracer dyes and retrieval methods to improve this technique.

Sentinel European Node Trial (SENT): 3-year results of sentinel node biopsy in oral cancer

PURPOSE

Optimum management of the N0 neck is unresolved in oral cancer. Sentinel node biopsy (SNB) can reliably detect microscopic lymph node metastasis. The object of this study was to establish whether the technique was both reliable in staging the N0 neck and a safe oncological procedure in patients with early-stage oral squamous cell carcinoma.

METHODS

An European Organisation for Research and Treatment of Cancer-approved prospective, observational study commenced in 2005. Fourteen European centres recruited 415 patients with radiologically staged T1-T2N0 squamous cell carcinoma. SNB was undertaken with an average of 3.2 nodes removed per patient. Patients were excluded if the sentinel node (SN) could not be identified. A positive SN led to a neck dissection within 3 weeks. Analysis was performed at 3-year follow-up.

RESULTS

An SN was found in 99.5% of cases. Positive SNs were found in 23% (94 in 415). A false-negative result occurred in 14% (15 in 109) of patients, of whom eight were subsequently rescued by salvage therapy. Recurrence after a positive SNB and subsequent neck dissection occurred in 22 patients, of which 16 (73%) were in the neck and just six patients were rescued. Only minor complications (3%) were reported following SNB. Disease-specific survival was 94%. The sensitivity of SNB was 86% and the negative predictive value 95%.

CONCLUSION

These data show that SNB is a reliable and safe oncological technique for staging the clinically N0 neck in patients with T1 and T2 oral cancer. EORTC Protocol 24021: Sentinel Node Biopsy in the Management of Oral and Oropharyngeal Squamous Cell Carcinoma.

Sentinel lymph node biopsy in T1/T2 squamous cell carcinomas of the tongue: A prospective study

Commonly used staging procedures often cannot predict the absence of cervical metastases (CM) in squamous cell carcinomas (SCCs) of the oral cavity. Due to the high incidence of occult CM in numerous N0 cases in the clinic, an elective neck dissection (ND) is performed. The sentinel lymph node biopsy (SNB) is a common concept in the modern surgical therapy of malignancies. The present study evaluates the applicability of this concept for T1/T2-SCC of the tongue. In a prospective clinical study, 10 consecutive patients with T1/T2-SCC of the tongue and cN0 necks, were enrolled. Following sentinel lymph node (SLN) scintigraphy, all patients underwent SNB with a γ-probe and a subsequent ND. SNB specimens were compared with histopathological assessments of surgical specimens from the ND. A total of 5 female and 5 male patients (mean age, 52 years; women, 62 years; men, 42 years), with a median follow-up time of 33.5 months (range, 10–40 months), were treated. All patients presented with detectable SLNs. In 7 cases, the SLN(s) and the residual ND were negative for CM. In 3 cases, the SLN(s) were positive without further CM in the other neck nodes. Furthermore, 1 patient showed additional CMs after 10 months in the contralateral neck and lung metastasis after 18 months, but none at the time of the initial treatment. The concept of an SNB appears to be applicable to the management of the cN0 neck in small SCC of the tongue. The role of SNB in the management of SCC requires further investigation by prospective trials with larger patient numbers.

Sentinel lymph node localization using 1 % isosulfan blue dye in cases of early oral cavity and oropharyngeal squamous cell carcinoma

To study the use of 1 % isosulfan blue dye in identifying sentinel node, sensitivity and specificity of frozen section and predictive value of sentinel node in predicting other nodal status in the cases of oral cavity and oropharyngeal squamous cell carcinoma. 15 patients of oral cavity and oropharyngeal SCC with clinically N0 neck, who required WLE of the primary lesion as well as neck dissection as per recommended treatment protocol, were selected from OPD. 1 % Isosulfan dye was injected peritumorally intraoperatively after the induction of general anaesthesia. Neck dissection was performed and first node taking up the blue dye was identified, dissected, removed and was sent for frozen section. In two of the 15 cases a sentinel node was identified (sensitivity of the technique-13 %). Both the sentinel nodes were positive for presence of metastasis on final histopathology (specificity-100 %). However, five cases had nodal metastasis on final histopathological examination of the neck dissection specimen (sensitivity of sentinel lymph node biopsy-40 %). Frozen section examination had a sensitivity and specificity of 100 %. All data was analyzed using SPSS 16 software. Use of 1 % Isosulfan Dye for identification of sentinel node is a simple and cheap technique, however, it has low sensitivity as compared to the use of triple diagnostic procedure consisting of lymphoscintigraphy, per op gamma probe localization and using isosulfan dye for sentinel node identification. Sentinel lymph node is representative of nodal status and correlates well with the final histopathological examination of the dissected neck nodes.

[Intraoperative frozen section diagnosis of head and neck tumors: possibilities, limitations, pitfalls and tips for the daily practice]

Intraoperative consultation (synonym: frozen section diagnostics) has increasingly gained significance for the daily practice in head and neck surgery. The main aim of this investigation method which is usually associated with much stress and effort is to facilitate an optimal and timely oncological surgical treatment of neoplastic diseases with a minimum rate of postoperative functional disturbance. In order to achieve this purpose pathologists are expected to deliver as much correct information as possible to accurately influence intraoperative surgical decisions. At the same time this aim should be reached without significantly and unnecessarily increasing the workload for the pathology laboratory and without significantly inducing tissue artifacts. This would otherwise negatively influence the tissue quality for permanent section examination and consequently the overall quality of diagnosis and tumor staging. Thus, the quality and efficacy of frozen sections span a spectrum with the highest quality having the least possible false negative rate on the one hand and a false positive result of approximately zero on the other hand. Sticking to this approach would result in a high positive impact on the surgical treatment of a variety of neoplastic diseases and help to minimize or even eliminate the rate of medicolegal consequences.

Pathologic evaluation of sentinel lymph nodes in oral squamous cell carcinoma

BACKGROUND

The objective of this study was to determine the relative efficacy of different methods of pathologic evaluation of sentinel lymph nodes.

METHODS

In this prospective study, sentinel nodes were evaluated for occult metastasis using frozen section, imprint-cytology, hematoxylin-eosin staining, serial step sectioning (SSS) with hematoxylin-eosin, and immunohistochemistry (IHC). Metastases were classified into macrometastasis (>2.0 mm), micrometastasis (0.2 mm-2.0 mm), isolated tumor cells (<0.2 mm).

RESULTS

Occult metastasis was detected in 20 of 80 patients. Frozen section and imprint cytology identified metastasis in 10 of 20 patients, hematoxylin-eosin stain in 13 patients; SSS upstaged the disease in a further 7 patients (9%). Frozen section detected macrometastasis in 7 of 8 cases but failed to detect smaller metastases (missed micrometastasis in 4 of 7 and isolated tumor cells in 5 of 5). SSS upstaged the disease by 10%, and sensitivity and negative predictive value of SSS with hematoxylin-eosin stain were 90% and 97%, respectively.

CONCLUSION

Frozen section and imprint cytology are not effective in identifying occult metastasis. IHC and SSS are required to identify micrometastasis and isolated tumor cells.

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.

Contemporary management of cancer of the oral cavity

Oral cancer represents a common entity comprising a third of all head and neck malignant tumors. The options for curative treatment of oral cavity cancer have not changed significantly in the last three decades; however, the work up, the approach to surveillance, and the options for reconstruction have evolved significantly. Because of the profound functional and cosmetic importance of the oral cavity, management of oral cavity cancers requires a thorough understanding of disease progression, approaches to management and options for reconstruction. The purpose of this review is to discuss the most current management options for oral cavity cancers.

Pemphigus vulgaris antigen mRNA quantification for the staging of sentinel lymph nodes in head and neck cancer

Background:

Molecular diagnosis has been proposed to enhance the intra-operative diagnosis of sentinel lymph node (SLN) invasion in head and neck squamous cell carcinoma (HNSCC). Although cytokeratin (CK) mRNA quantification with real-time reverse transcriptase-PCR (QRT–PCR) has produced encouraging results, the more discriminating markers remain to be identified.

Methods:

Pemphigus vulgaris antigen (PVA), squamous cell carcinoma antigen (SCCA), and CK17 mRNA were quantified using QRT–PCR, and the results were compared with an extensive histopathological examination of the entire SLNs on 78 SLNs harvested from 22 patients with HNSCC.

Results:

SCCA and CK17 quantification showed significantly higher mRNA values for macrometastases (MAs) than for either negative or isolated tumour cell (ITC) SLNs (P<0.01). Pemphigus vulgaris antigen allowed the discrimination of all MAs and micrometastases from both negative and ITC SLNs (P<0.001). For the neck staging of patients, considering metastatic vs non-metastatic status, receiver-operating characteristic curve analysis found areas under the curve of 93.8, 97.9, and 100% for CK17, SCCA, and PVA, respectively. With PVA, a cutoff value of 562 copies per 100 ng of cDNA permitted the correct distinction between patients with positive as opposed to negative neck nodes in all cases.

Conclusion:

PVA seems to be a highly promising marker for accurate intra-operative SLN staging in HNSCC by QRT–PCR.

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.

Predictive value of sentinel node biopsy in head and neck cancer

CONCLUSIONS

The negative predictive value (NPV) of sentinel lymph node biopsy (SNB) in this study was 95%. The accuracy of SNB compared to histopathologic evaluation of surgical specimen of subsequent neck dissection (ND) was 96%.

OBJECTIVE

To evaluate NPV of SNB in head and neck cancer.

PATIENTS AND METHODS

This was a prospective clinical study comprising 35 patients (50 necks) with squamous cell carcinoma (SCC) of head and neck with clinically (cN0) and radiologically negative necks, without previous treatment, who underwent SNB with gamma probe and subsequent ND. The NPV, accuracy, sensitivity, and specificity of SNB were compared to histopathologic assessment of surgical specimens from NDs. Negative sentinel lymph nodes (SLNs) on histopathology were evaluated with step serial section (SSS) and immunohistochemistry (IHC). When a neck had a positive SLN, all lymph nodes of subsequent NDs were studied with SSS and IHC.

RESULTS

There were primaries of the oral cavity (n=24), lip (n=3), oropharynx (n=3), and larynx (n=5). All patients had detected SLNs. In all, 41 necks were SLN-negative on histopathologic evaluation but 2 (5%) had metastases in non-SLNs after ND. Of these 41 necks, SLNs were level Ib (26%), IIa (45%), III (21%), and IV (8%). Nine necks presented positive SLN on histopathologic evaluation, level Ib (n=3), IIa (n=5), and III (n=2), and subsequent NDs were negative on conventional histopathologic analysis, but after SSS and IHC, two presented micrometastases.

Need for intensive histopathologic analysis to determine lymph node metastases when using sentinel node biopsy in oral cancer

OBJECTIVE

To determine the predictive value of sentinel node biopsy (SNB)-assisted neck dissection in patients with oral squamous cell carcinoma (SCC) stage T1 to 2N0M0 and to determine the incidence of subclinical metastases.

STUDY DESIGN

Prospective cohort study.

METHODS

Fifty-one patients with clinically N0 neck underwent SNB-assisted neck dissection. The localization of the sentinel node (SN) was determined using dynamic and planar lymphoscintigraphy and single photon emission computed tomography-computed tomography. Histopathologic examination of the harvested SN was performed using step-serial sectioning with hematoxylin-eosin (H&E) and immunohistochemistry on formalin-fixed, paraffin-embedded tissue.

RESULTS

A total of 181 SNs were excised with a median of 3 (range 1-7) SNs per patient. Four percent (2 of 51) of patients with subclinical (occult) lymph node metastasis would have been identified using routine H&E staining, whereas the 18% (9 of 49) were upstaged as a result of additional histopathology when the H&E evaluation was negative. Overall, the incidence of subclinical metastases was 22% (11 of 51).

CONCLUSION

In this study, SNB-assisted neck dissection proved to be technically feasible in identifying subclinical metastasis, thus accurately staging the neck with a high degree of sensitivity in patients with oral SCC T1 to 2N0M0 when additional histopathology was performed. The vast majority of patients in this study would have been spared selective neck dissection had reliance on SNB been used and selective neck dissection performed only in the case of a positive SN. Future studies should focus on determining whether SNB alone reduces patient morbidity and whether this is as equally effective in the treatment of cervical nodal metastases as compared with selective neck dissection in patients with oral SCC.

Sentinel lymph node biopsy or elective neck dissection for patients with oral squamous cell carcinoma?

Sentinel lymph node biopsy (SNB) seems to be a promising method for staging clinically N0 neck in patients with oral squamous cell carcinoma (OSCC). In the present study, SNB was performed on 46 patients having elective neck dissection (END; six bilateral dissections) for T1-T3N0 OSCC. Sentinel lymph nodes (SLN) were first examined according to only slightly modified standard histopathologic protocol including sections at 1-2 mm intervals and H&E staining. SLN that appeared false negative (i.e. metastatic non-SLN without metastasis in a SLN) after the initial histopathologic examination were further assessed by step sectioning at 150 microm intervals and immunohistochemistry. Of the 47 neck sides with at least one SLN identified, nine contained metastasis in nine patients. After the initial histopathologic examination, SLNs were negative for malignant cells in four out of the nine metastatic neck sides. In one neck side, two metastatic SLNs were detected after the additional meticulous histopathologic work-up of the initially false negative SLNs. Therefore, in three neck sides the SLN did not contain metastasis although there was a metastasis in a non-SLN. In all these three cases with a false negative SLN, only one SLN had been identified. The sensitivity of the method (employing extensive histopathologic work-up) for detection of occult cervical metastasis was 67% (6/9 neck sides). The sensitivity of SNB for detection of occult metastasis seems to be poor in cases where only one SLN can be identified. The results of this study do not entitle us to entirely replace END by SNB in patients with OSCC.

Sentinel lymph nodes in cancer of the oral cavity: is central step-sectioning enough?

BACKGROUND

Extended histopathologic work-up has increased the detection of micrometastasis in sentinel lymph nodes in malignant melanoma and breast cancer. The aim of this study was to examine if (A) step-sectioning of the central 1000 microM at 250 microM levels with immunostaining were accurate when compared with (B) step-sectioning and immunostaining of the entire sentinel lymph node at 250 microM levels.

METHODS

Forty patients with T1/T2 cN0 oral cancer were enrolled. Three patients were excluded. In one patient no sentinel lymph node was identified. The remaining two had unidentified sentinel lymph nodes due to lymphoscintigraphic and surgical sampling error. The central 1000 microM of 147 sentinel lymph nodes were step-sectioned in 250-microm intervals and stained with hematoxylin and eosin and CK-KL1. All lymph nodes were recorded as negative or positive for macrometastases or micrometastases. After inclusion of the last patient the residual tissue of the lymph nodes was totally step-sectioned at 250-microm intervals and re-classified. The tumor deposits were divided into macrometastases and micrometastases and ITC.

RESULTS

Method (A) upstaged 17 lymph nodes and 11 patients compared with method (B), which upstaged 22 lymph nodes and 11 patients. Seven of the patients with positive lymph nodes did not change stage. However, four lymph nodes changed from micrometastases to macrometastases. One patient changed from a micrometastasis to four micrometastases. One pN2c patient with bilateral micrometastases did not change stage, but an additional ipsilateral lymph node with a micrometastasis was identified.

CONCLUSION

Larger tumor deposits and more metastases are identified by more extensive sectioning of the sentinel lymph nodes. None of the patients was false-negative due to histopathologic sampling error, but the results indicate that central step-sectioning of the central 1000 microM cannot completely be relied upon for accurate staging of the patients.

Sentinel Node Biopsy for Oral and Oropharyngeal Squamous Cell Carcinoma of the Head and Neck

OBJECTIVES

The aims were to assess the technical feasibility of sentinel node biopsy (SNB), to validate SNB against elective neck dissection, and to report the results of the clinical application of the SNB concept for early oral and oropharyngeal squamous cell carcinoma.

STUDY DESIGN

Prospective consecutive cohort analysis.

METHODS

Between 2000 and 2006, a total of 79 patients were included. Lymphatic mapping consisted of preoperative lymphoscintigraphy and intraoperative use of a hand-held gammaprobe. Twenty-eight patients were assessed for feasibility and validation; the SNB was done in context with an elective neck dissection. Fifty-one patients were evaluated in an observational trial; elective neck dissection was performed only in case of positive SNB.

RESULTS

Validation revealed a sentinel node detection rate by lymphoscintigraphy of 93%, with the gammaprobe of 100%. The negative predictive value of a negative SNB was 100%. During the observational trial 40% of the patients were upstaged as a result of a positive SNB. Intraoperative frozen section analysis showed a negative predictive value of 83%. Two patients (6%) with negative SNB experienced a neck recurrence, the negative predictive value of SNB was therefore 94%. Patients with positive SNB were treated successfully with elective neck dissection.

CONCLUSIONS

SNB is technically feasible and reproducible with a high sentinel node detection rate. Validation against elective neck dissection revealed a negative predictive value of 100%. Application of the SNB concept in clinical practice was very successful. The recurrence rate within the neck was very low and the morbidity and cost of an elective neck dissection could be spared to 60% of the patients.

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.

Elective neck dissection for carcinomas of the oral cavity: occult metastases, neck recurrences, and adjuvant treatment of pathologically positive necks

BACKGROUND

Supraomohyoid neck dissection (SOHND) is currently performed in patients with carcinoma of the oral cavity with clinically negative neck. Most investigators consider SOHND as a staging procedure.

METHODS

Records of 100 patients with cancer of the oral cavity and clinically negative neck undergoing SOHND were reviewed. The rate and significance of occult metastases are evaluated, the neck recurrences are analyzed and the indication of adjuvant radiation of pN+ necks is discussed.

RESULTS

In 34 of 1814 of analyzed lymph nodes, metastatic disease was detected as follows: 30 macrometastases and 4 micrometastases. In 13 of 34 metastases (38%), extracapsular spread was observed. Twenty of 100 patients (20%) had to be upstaged. In 9 of 87 (10%) patients without local recurrence and with a minimal follow-up of 24 months, 5 ipsilateral (4 within the dissection field) and 5 contralateral neck recurrences were observed. Regional recurrence developed in 4% and 35% of patients with pN0 and pN+ necks, respectively.

CONCLUSIONS

In 20% of patients with oral cavity tumors and pN0 neck, occult metastases were disclosed. Neck recurrences developed significantly more often in patients with pN+ than in those with pN0 necks. To evaluate the exact indication for an adjuvant treatment of patients with cN0/pN+ necks, prospective studies should be performed.

The Diagnostic Accuracy of Reverse Transcription-PCR Quantification of Cytokeratin mRNA in the Detection of Sentinel Lymph Node Invasion in Oral and Oropharyngeal Squamous Cell Carcinoma: A Comparison with Immunohistochemistry

PURPOSE

The main goal of sentinel lymph node (SLN) detection in head and neck squamous cell carcinomas is to limit neck dissections to pN+ cases only. However, intraoperative + diagnosis cannot be routinely done using the current gold standard, serial step sectioning with immunohistochemistry. Real-time quantitative reverse transcription-PCR (RT-PCR) is potentially compatible with intraoperative use, proving highly sensitive in detecting molecular markers. This study postoperatively assessed the accuracy of quantitative RT-PCR in staging patients from their SLN.

EXPERIMENTAL DESIGN

A combined analysis on the same SLN by serial step sectioning with immunohistochemistry and quantitative RT-PCR targeting cytokeratins 5, 14, and 17 was done in 18 consecutive patients with oral or oropharyngeal squamous cell carcinoma and 10 control subjects.

RESULTS

From 71 lymph nodes examined, mRNA levels (KRT) were linked to metastasis size for the three cytokeratins studied (Pearson correlation coefficient, r = 0.89, 0.73, and 0.77 for KRT 5, 14, and 17 respectively; P < 0.05). Histopathology-positive SLNs (macro- and micrometastases) showed higher mRNA values than negative SLNs for KRT 17 (P < 10(-4)) and KRT 14 (P < 10(-2)). KRT 5 showed nonsignificant results. KRT 17 seemed to be the most accurate marker for the diagnosis of micrometastases of a size >450 mum. Smaller micrometastases and isolated tumor cells did not provide results above the background level. Receiver operating characteristic curve analysis for KRT 17 identified a cutoff value where patient staging reached 100% specificity and sensitivity for macro- and micrometastases.

CONCLUSION

Quantitative RT-PCR for SLN staging in cN(0) patients with oral and oropharyngeal squamous cell carcinoma seems to be a promising approach.

Elective and therapeutic selective neck dissection

Selective neck dissection is a modification of the more comprehensive modified radical or radical neck dissection that is designed to remove only those nodal levels considered to be at risk for harboring nodal metastases. The role of selective neck dissection continues to evolve: while initially designed as a staging and diagnostic procedure for patients without clinical evidence of nodal disease, a growing body of literature suggests that selective neck dissection has a therapeutic role in patients with clinical and histologic evidence of nodal metastases. The rationale behind selective neck dissection, its application in the clinically negative but histologically node-positive neck and the extended application of selective neck dissection in patients with clinical evidence of nodal disease are discussed.

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.

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.

The second international conference on sentinel node biopsy in mucosal head and neck cancer

BACKGROUND

The Second International Conference on Sentinel Node Biopsy in Mucosal Head and Neck Cancer was hosted by the Department of Otorhinolaryngology, Head and Neck Surgery of the University Hospital in Zurich, Switzerland, from September 12 to 13, 2003. The aims of this conference were to present the results of validation studies and to achieve a consensus on methodological requirements.

METHODS

More than 80 delegates from 20 countries attended the conference. The presented validation studies were summarized and compared with the literature. Consensus was achieved concerning requirements for lymphatic mapping and histopathologic work-up.

RESULTS

Twenty centers presented results on 379 patients with cN0 disease. Sentinel nodes were identified in 366 (97%) of 379. Of these 366, 103 (29%) were positive for occult metastasis, and 263 (71%) were negative. Of those 263 patients, 11 patients (4%) showed nodal disease not revealed by the sentinel lymph node biopsy (SNB). The negative predictive value of a negative sentinel node for the remaining neck was 96%. The consensus conference resulted in the use of a radiotracer, lymphoscintigraphy, and a handheld gamma probe for lymphatic mapping as minimal requirements. The use of conventional hematoxylin and eosin staining and immunohistochemistry for cytokeratin is mandatory. Step-sectioning of the entire node at intervals of 150 mum is recommended.

CONCLUSIONS

The conference attracted delegates from all over the world, thus underscoring the high interest in the topic. With regard to the presented data and the data from the literature, SNB for early oral and oropharyngeal cancer is sufficiently validated. The consensus conference resulted in the definition of minimal methodological requirements for accurate SNB.