Immunohistochemical Studies in the Identification of Lymph Node Micrometastases in Patients with Squamous Cell Carcinoma of the Head and Neck

Personalized neck irradiation guided by sentinel lymph node biopsy in patients with squamous cell carcinoma of the oropharynx, larynx or hypopharynx with a clinically negative neck: (Chemo)radiotherapy to the PRIMary tumor only. Protocol of the PRIMO study

Background

Elective neck irradiation (ENI) is performed in head and neck cancer patients treated with definitive (chemo)radiotherapy. The aim is to eradicate nodal metastases that are not detectable by pretreatment imaging techniques. It is conceivable that personalized neck irradiation can be performed guided by the results of sentinel lymph node biopsy (SLNB). It is expected that ENI can be omitted to one or both sides of the neck in 9 out of 10 patients, resulting in less radiation side effects with better quality of life.

Methods/design

This is a multicenter randomized controlled trial aiming to compare safety and efficacy of treatment with SLNB guided neck irradiation versus standard bilateral ENI in 242 patients with cN0 squamous cell carcinoma of the oropharynx, larynx or hypopharynx for whom bilateral ENI is indicated. Patients randomized to the experimental-arm will undergo SLNB. Based on the histopathologic status of the SLNs, patients will receive no ENI (if all SLNs are negative), unilateral neck irradiation only (if a SLN is positive at one side of the neck) or bilateral neck irradiation (if SLNs are positive at both sides of the neck). Patients randomized to the control arm will not undergo SLNB but will receive standard bilateral ENI. The primary safety endpoint is the number of patients with recurrence in regional lymph nodes within 2 years after treatment. The primary efficacy endpoint is patient reported xerostomia-related quality of life at 6 months after treatment.

Discussion

If this trial demonstrates that the experimental treatment is non-inferior to the standard treatment in terms of regional recurrence and is superior in terms of xerostomia-related quality of life, this will become the new standard of care.

Diagnostic test accuracy of sentinel lymph node biopsy in squamous cell carcinoma of the oropharynx, larynx, and hypopharynx: A systematic review and meta-analysis

The aim of this meta-analysis was to determine the diagnostic test accuracy of sentinel lymph node biopsy (SLNB) in patients with oropharyngeal, laryngeal, and hypopharyngeal squamous cell carcinoma (SCC). For this purpose, MEDLINE, EMBASE, and Web of Science were searched from inception to March 8, 2022. Included were studies evaluating diagnostic test accuracy of SLNB to identify cervical lymph node metastases with elective neck dissection or follow-up as reference. A bivariate generalized linear mixed model approach was used for the meta-analysis. Nineteen studies were eligible, evaluating 377 cases in total. The pooled estimates of sensitivity and negative predictive value were 0.93 (95% CI: 0.86-0.96) and 0.97 (95% CI: 0.94-0.98), respectively. The excellent accuracy of SLNB justifies a place in the diagnostic workup of patients with larynx and pharynx SCC. Randomized trials are required to demonstrate oncologic safety and benefits on treatment related morbidity and quality of life when omitting elective neck treatment based on SLNB.

CT Lymphography Using Lipiodol® for Sentinel Lymph Node Biopsy in Early-Stage Oral Cancer

This study evaluated sentinel lymph node (SLN) identification with CT lymphography (CTL) following peritumoral administration of Lipiodol^® relative to conventional ^99mTc-nanocolloid lymphoscintigraphy (including SPECT/CT) in 10 early-stage oral cancer patients undergoing SLN biopsy. Patients first underwent early dynamic and static scintigraphy after peritumoral administration of ^99mTc-nanocolloid. Subsequently, Lipiodol^® was administered at the same injection sites, followed by fluoroscopy and CT acquisition. Finally, late scintigraphy and SPECT/CT were conducted, enabling the fusion of late CTL and SPECT imaging. The next day, designated SLNs were harvested, radiographically examined for Lipiodol^® uptake and histopathologically assessed. Corresponding images of CT, ^99mTc-nanocolloid lymphoscintigraphy and SPECT/late CTL fusion were evaluated. ^99mTc-nanocolloid lymphoscintigraphy identified 21 SLNs, of which 7 were identified with CTL (33%). CTL identified no additional SLNs and failed to identify any SLNs in four patients (40%). Out of six histopathologically positive SLNs, two were identified by CTL (33%). Radiographic examination confirmed Lipiodol^® uptake in seven harvested SLNs (24%), of which five were depicted by CTL. CTL using Lipiodol^® reached a sensitivity of 50% and a negative predictive value (NPV) of 75% (median follow-up: 12.3 months). These results suggest that CTL using Lipiodol^® is not a reliable technique for SLN mapping in early-stage oral cancer.

Neck Dissections Based on Sentinel Lymph Node Navigation Versus Elective Neck Dissections in Early Oral Cancers: A Randomized, Multicenter, and Noninferiority Trial

PURPOSE

This study aimed to compare patients with early oral cavity squamous cell carcinoma (OCSCC) (tumor category [T] 1-2, node-negative, and no distant metastasis) treated with traditional elective neck dissection (ND) with those managed by sentinel lymph node biopsy (SLNB) using survival and neck function and complications as end points.

METHODS

Sixteen institutions in Japan participated in the study (trial registration number: UMIN000006510). Patients of age ≥ 18 years with histologically confirmed, previously untreated OCSCC (Union for International Cancer Control TNM Classification of Malignant Tumors 7th edition T1-2, node-negative no distant metastasis), with ≥ 4 mm (T1) depth of invasion, were randomly assigned to undergo standard selective ND (ND group; n = 137) or SLNB-navigated ND (SLNB group; n = 134). The primary end point was the 3-year overall survival rate, with a 12% noninferiority margin; secondary end points included postoperative neck functionality and complications and 3-year disease-free survival. Sentinel lymph nodes underwent intraoperative multislice frozen section analyses for the diagnosis. Patients with positive sentinel lymph nodes underwent either one-stage or second-look ND.

RESULTS

Pathologic metastasis-positive nodes were observed in 24.8% (34 of 137) and 33.6% (46 of 134) of patients in the ND and SLNB groups, respectively (P = .190). The 3-year overall survival in the SLNB group (87.9%; lower limit of one-sided 95% CI, 82.4) was noninferior to that in the ND group (86.6%; lower limit 95% CI, 80.9; P for noninferiority < .001). The 3-year disease-free survival rate was 78.7% (lower limit 95% CI, 72.1) and 81.3% (75.0) in the SLNB and ND groups, respectively (P for noninferiority < .001). The scores of neck functionality in the SLNB group were significantly better than those in the ND group.

CONCLUSION

SLNB-navigated ND may replace elective ND without a survival disadvantage and reduce postoperative neck disability in patients with early-stage OCSCC.

What is the role of sentinel lymph node biopsy in the management of oral cancer in 2020?

Approximately 70–80% of patients with cT1-2N0 oral squamous cell carcinoma (OSCC) ultimately prove to have no cancer in the cervical lymphatics on final pathology after selective neck dissection. As a result, sentinel lymph node biopsy (SLNB) has been adopted during the last decade as a diagnostic staging method to intelligently identify patients who would benefit from formal selective lymphadenectomy or neck irradiation. While not yet universally accepted, SLNB is now incorporated in many national guidelines. SLNB offers a less invasive alternative to elective neck dissection (END), and has some advantages and disadvantages. SLNB can assess the individual drainage pattern and, with step serial sectioning and immunohistochemistry (IHC), can enable the accurate detection of micrometastases and isolated tumor cells (ITCs). Staging of the neck is improved relative to END with routine histopathological examination. The improvements in staging are particularly notable for the contralateral neck and the pretreated neck. However, for floor of mouth (FOM) tumors, occult metastases are frequently missed by SLNB due to the proximity of activity from the primary site to the lymphatics (the shine through phenomenon). For FOM cancers, it is advised to perform either elective neck dissection or superselective neck dissection of the preglandular triangle of level I. New tracers and techniques under development may improve the diagnostic accuracy of SLNB for early-stage OSCC, particularly for FOM tumors. Treatment of the neck (either neck dissection or radiotherapy), although limited to levels I–IV, remains mandatory for any positive category of metastasis (macrometastasis, micrometastasis, or ITCs). Recently, the updated EANM practical guidelines for SLN localization in OSCC and the surgical consensus guidelines on SLNB in patients with OSCC were published. In this review, the current evidence and results of SLNB in early OSCC are presented.

Sentinel lymph node detection in oral cancer: a within-patient comparison between [99mTc]Tc-tilmanocept and [99mTc]Tc-nanocolloid

Purpose

Sentinel lymph node (SLN) biopsy has proven to reliably stage the clinically negative neck in early-stage oral squamous cell carcinoma (OSCC). [^99mTc]Tc-tilmanocept may be of benefit in OSCC with complex lymphatic drainage patterns and close spatial relation to SLNs.

Methods

A prospective within-patient evaluation study was designed to compare [^99mTc]Tc-tilmanocept with [^99mTc]Tc-nanocolloid for SLN detection. A total of 20 patients with early-stage OSCC were included, who underwent lymphoscintigraphy with both tracers. Both lymphoscintigraphic images of each patient were evaluated for SLN detection and radiotracer distribution at 2–4 h post-injection.

Results

The injection site’s remaining radioactivity was significantly lower for [^99mTc]Tc-tilmanocept (29.9%), compared with [^99mTc]Tc-nanocolloid (60.9%; p < 0.001). Radioactive uptake in SLNs was significantly lower for [^99mTc]Tc-tilmanocept (1.95%) compared with [^99mTc]Tc-nanocolloid (3.16%; p = 0.010). No significant difference was seen in SLN to injection site ratio in radioactivity between [^99mTc]Tc-tilmanocept (0.066) and [^99mTc]Tc-nanocolloid (0.054; p = 0.232). A median of 3.0 and 2.5 SLNs were identified with [^99mTc]Tc-tilmanocept and [^99mTc]Tc-nanocolloid, respectively (p = 0.297). Radioactive uptake in higher echelon nodes was not significantly different between [^99mTc]Tc-tilmanocept (0.57%) and [^99mTc]Tc-nanocolloid (0.86%) (p = 0.052). A median of 2.0 and 2.5 higher echelon nodes was identified with [^99mTc]Tc-tilmanocept and [^99mTc]Tc-nanocolloid, respectively (p = 0.083).

Conclusion

[^99mTc]Tc-tilmanocept had a higher injection site clearance, but at the same time a lower uptake in the SLN, resulting in an SLN to injection site ratio, which was not significantly different from [^99mTc]Tc-nanocolloid. The relatively low-radioactive uptake in SLNs of [^99mTc]Tc-tilmanocept may limit intraoperative detection of SLNs, but can be overcome by a higher injection dose.

Electronic supplementary material

The online version of this article (10.1007/s00259-020-04984-8) contains supplementary material, which is available to authorized users.

Elective Neck Dissection or Sentinel Lymph Node Biopsy in Early Stage Oral Cavity Cancer Patients: The Dutch Experience

Background: Sentinel lymph node biopsy (SLNB) has been introduced as a diagnostic staging modality for detection of occult metastases in patients with early stage oral cancer. Comparisons regarding accuracy to the routinely used elective neck dissection (END) are lacking in literature. Methods: A retrospective, multicenter cohort study included 390 patients staged by END and 488 by SLNB. Results: The overall sensitivity (84% vs. 81%, p = 0.612) and negative predictive value (NPV) (93%, p = 1.000) were comparable between END and SLNB patients. The END cohort contained more pT2 tumours (51%) compared to the SLNB cohort (23%) (p < 0.001). No differences were found for sensitivity and NPV between SLNB and END divided by pT stage. In floor-of-mouth (FOM) tumours, SLNB had a lower sensitivity (63% vs. 92%, p = 0.006) and NPV (90% vs. 97%, p = 0.057) compared to END. Higher disease-specific survival (DSS) rates were found for pT1 SLNB patients compared to pT1 END patients (96% vs. 90%, p = 0.048). Conclusion: In the absence of randomized clinical trials, this study provides the highest available evidence that, in oral cancer, SLNB is as accurate as END in detecting occult lymph node metastases, except for floor-of-mouth tumours.

Incidence of Occult Lymph Node Metastasis in Primary Larynx Squamous Cell Carcinoma, by Subsite, T Classification and Neck Level: A Systematic Review

Background: Larynx cancer is a common site for tumors of the upper aerodigestive tract. In cases with a clinically negative neck, the indications for an elective neck treatment are still debated. The objective is to define the prevalence of occult metastasis based on the subsite of the primary tumor, T classification and neck node levels involved. Methods: All studies included provided the rate of occult metastases in cN0 larynx squamous cell carcinoma patients. The main outcome was the incidence of occult metastasis. The pooled incidence was calculated with random effects analysis. Results: 36 studies with 3803 patients fulfilled the criteria. The incidence of lymph node metastases for supraglottic and glottic tumors was 19.9% (95% CI 16.4–23.4) and 8.0% (95% CI 2.7–13.3), respectively. The incidence of occult metastasis for level I, level IV and level V was 2.4% (95% CI 0–6.1%), 2.0% (95% CI 0.9–3.1) and 0.4% (95% CI 0–1.0%), respectively. For all tumors, the incidence for sublevel IIB was 0.5% (95% CI 0–1.3). Conclusions: The incidence of occult lymph node metastasis is higher in supraglottic and T3–4 tumors. Level I and V and sublevel IIB should not be routinely included in the elective neck treatment of cN0 laryngeal cancer and, in addition, level IV should not be routinely included in cases of supraglottic tumors.

Depth of invasion in patients with early stage oral cancer staged by sentinel node biopsy

BACKGROUND

To investigate if depth of invasion (DOI) can predict occult nodal disease in patients with cT1-2N0 (7th TNM) oral squamous cell carcinoma (OSCC) staged by sentinel lymph node biopsy (SLNB).

METHODS

In 199 OSCC patients, DOI measurements and SLNB were performed.

RESULTS

Metastases were found in 64 of 199 patients (32%). Of these 64 patients, the mean DOI was 6.6 mm compared to 4.7 mm in patients without metastases (P = .003). The ROC-curve showed an area under the curve of 0.65 with a most optimal cutoff point of 3.4 mm DOI (sensitivity 83% and specificity 47%). Regional metastases were found in 15% of patients with DOI ≤ 3.4 mm.

CONCLUSION

DOI seems to be a poor predictor for regional metastasis in patients with cT1-2N0 OSCC. Therefore, staging of the neck using SLNB in patients with early stage oral cancer should also be performed in tumors with limited DOI and probably in T3 (8th TNM) OSCC ≤4 cm diameter.

Additional non-sentinel lymph node metastases in early oral cancer patients with positive sentinel lymph nodes

To determine risk factors for additional non-sentinel lymph node metastases in neck dissection specimens of patients with early stage oral cancer and a positive sentinel lymph node biopsy (SLNB). A retrospective analysis of 36 previously untreated SLNB positive patients in our institution and investigation of currently available literature of positive SLNB patients in early stage oral cancer was done. Degree of metastatic involvement [classified as isolated tumor cells (ITC), micro- and macrometastasis] of the sentinel lymph node (SLN), the status of other SLNs, and additional non-SLN metastases in neck dissection specimens were analyzed. Of 27 studies, comprising 511 patients with positive SLNs, the pooled prevalence of non-SLN metastasis in patients with positive SLNs was 31 %. Non-SLN metastases were detected (available from 9 studies) in 13, 20, and 40 % of patients with ITC, micro-, and macrometastasis in the SLN, respectively. The probability of non-SLN metastasis seems to be higher in the case of more than one positive SLN (29 vs. 24 %), the absence of negative SLNs (40 vs. 19 %), and a positive SLN ratio of more than 50 % (38 vs. 19 %). Additional non-SLN metastases were found in 31 % of neck dissections following positive SLNB. The presence of multiple positive SLNs, the absence of negative SLNs, and a positive SLN ratio of more than 50 % may be predictive factors for non-SLN metastases. Classification of SLNs into ITC, micro-, and macrometastasis in the future SLNB studies is important to answer the question if treatment of the neck is always needed after positive SLNB.

[Prediction of Post-operative Lymph Node Metastasis with a Molecular Biological Test in Head and Neck Cancer]

We assessed herein the post-operative lymph node metastasis in head and neck cancer, using the One-step nucleotide amplification (OSNA) method targeting matrix metalloproteinase 7 (MMP-7). Compared with the pathological test, the molecular biological test revealed more lymph node metastasis, resulting in poor prognosis. Six cases, of which the number of lymph node metastasis was the same between pathological and molecular biological test, survived. On the other hand, three of four cases, in which number of lymph node metastasis in the molecular biological test were larger than the pathological test, died from metastasis. We concluded that the pathological test underestimated metastasis, and OSNA with MMP-7 was useful for the prediction of post-operative lymph node metastasis.

Advances in diagnostic modalities to detect occult lymph node metastases in head and neck squamous cell carcinoma

Regional metastasis is a prominent feature of head and neck squamous cell carcinoma (HNSCC) and is an important prognostic factor. The currently available imaging techniques for assessment of the neck have limitations in accuracy; thus, elective neck dissection has remained the usual choice of management of the clinically N0 neck (cN0) for tumors with significant (≥20%) incidence of occult regional metastasis. As a consequence, the majority of patients without regional metastasis will undergo unnecessary treatment. The purpose of this review was to discuss new developments in techniques that potentially improve the accuracy of the assessment of the neck in patients with HNSCC. Although imaging has improved in the last decades, a limitation common to all imaging techniques is a lack of sensitivity for small tumor deposits. Therefore, complementary to improvements in imaging techniques, developments in more invasive diagnostic procedures, such as sentinel node biopsy (SNB) will add to the accuracy of diagnostic algorithms for the staging of the neck.

Prognostic value of level IV metastases from head and neck squamous cell carcinoma

BACKGROUND

The purpose of this study was to evaluate the prognostic value of level IV metastases in head and neck squamous cell carcinoma (HNSCC).

METHODS

The clinical and histopathological data of 111 patients with HNSCC with pN+ neck who underwent a primary tumor resection with unilateral or bilateral neck dissection were analyzed.

RESULTS

Level IV metastases were histopathologically proven in 33 patients (29.7%). Pulmonary metastases were observed in 12 of 33 patients (36.4%) with level IV metastases, and in 13 of 78 patients (16.7%) without level IV metastases (p = .04). Multivariate analyzes revealed a significant association between level IV metastases and pulmonary metastases (p = .038). However, an influence on overall (p = .65) or disease-free survival (p = .66) was not observed.

CONCLUSION

Level IV metastases seem to be a predictive factor for pulmonary metastases but not for overall and disease-free survival in patients with HNSCC.

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.

Immunohistochemistry, a valuable tool in detection of cervical lymph node micrometastases in head and neck squamous cell carcinoma: a prospective study

The regional failure after comprehensive clearance of neck metastasis and consequent pathological report of N0 disease has been reported fairly frequently. The role of recurrence of disease in the neck in the cases has been variously reported by different authors. The light microscopy does not detect the micrometastasis and the specimen is reported negative for metastasis. The presence of micrometastasis (the reason for neck failure) has been reported by many studies as 5-58 % (mean 19.6 %). These figures are significantly high. The present study was done to ascertain the micrometastasis after comprehensive neck clearance (pN0 report). Two groups of patients were included in this study. (1) Group I included patients with N0 necks (80 patients). (2) Group II included Patients with N+ necks (107 patients). We found that 20 % case were reported N0 (Group I) in light microscopy but on immunohistochemistry these were positive for disease. 15 % upstaging was reported in N+ cases (Group 2). Immunohistochemistry has been more sensitive for cancer detection and has significantly changed the tumor staging and its consequent management.

A novel approach to translymphatic chemotherapy targeting sentinel lymph nodes of patients with oral cancer using intra-arterial chemotherapy - preliminary study

Background

Recent progress in ICG (indocyanine green) fluorescence imaging has provided a means by which we can detect sentinel lymph nodes (SLNs) without the risk of exposing patients to radiation. Neck metastasis is the most significant prognostic factor. It is imperative that early metastasis can be controlled. Intra-arterial chemotherapy is performed in order to preserve organs and to improve prognosis when treating oral cancer.

Objective

Evaluate translymphatic chemotherapy targeting SLNs in patients with oral cancer using intra-arterial chemotherapy. Evaluation will be carried out through the measurement of CDDP concentrations in SLNs.

Methods

Five patients with tongue cancer (T3N0M0) were treated by intra-arterial chemotherapy as neoadjuvant chemotherapy from November 2010 to June 2011. After a week of chemotherapy, patients underwent surgical treatment including the partial resection of the tongue and neck dissection. Intra-arterial chemotherapy was administered at 50 mg/m² of CDDP either one or two times weekly. 5 mg of ICG was administered to the lingual artery at the beginning of surgery. SLNs were detected using ICG fluorescence imaging. 0.1 g of SLNs and non-SLNs were resected in order to measure CDDP concentrations. The rests of each of the SLNs were examined intraoperatively by routine frozen pathological examination. SLNs were also identified using radioactive injection the day prior to surgery.

Results

The mean CDDP concentrations in the SLNs and non-SLNs were 1.2 μg/g and 0.35 μg/g, respectively. Our intra- arterial infusion revealed that all metastatic lymph nodes, including SLNs, were without false negative SLNs. However, of 7 metastatic lymph nodes, one was not identified by means of conventional method.

Conclusion

Our findings verified the possibility that intra-arterial chemotherapy may be effective not only for organ preservation therapy, but also efficient in translymphatic chemotherapy targeting SLNs in patients with oral cancer through the use of ICG fluorescence imaging.

Current potential and limitations of molecular diagnostic methods in head and neck cancer

Traditional diagnostic methods such as clinical assessment, histopathological examination and imaging techniques are limited in their capacity to provide information on prognosis and treatment choice of head and neck cancer. In recent years, molecular techniques have been developed that enabled us to get more insight into the molecular biological cellular pathways underlying tumor progression and metastasis. Correlation of these molecular changes with clinical events has been explored. However, consistently useful markers have not been identified yet, although many promising developments are in progress. It may be expected that in the near future, molecular markers will be useful for clinical purposes. In this paper, an overview will be given of the several molecular techniques that may have potential to be introduced in clinical practice in the management of head and neck squamous cell carcinoma.

Stomach cancer: prevalence and significance of neck nodal metastases on sonography

The aim of this study was to determine the frequency of metastatic neck nodes detected using sonography in patients with stomach cancer at presentation according to primary subsite and to assess the effect of metastatic neck node detection on tumour staging. Imaging and histological records of 233 patients diagnosed with stomach cancer were reviewed. All patients underwent neck ultrasound at presentation with ultrasound-guided fine needle aspiration for cytology (FNAC) of sonographically abnormal neck nodes. Abnormal nodes were classified positive or negative for metastases based on the FNAC result. Clinical records were also reviewed for evidence of subsequent neck nodal metastases. Sonographically abnormal neck nodes were present in 14/233 (6.0%) patients; 7 were reactive and 7 were metastatic based on FNAC findings and clinical follow-up. Overall, 7/233 (3.0%) patients with stomach cancer had nodal metastases, although tumour stage was altered in only 2/233 (0.9%) patients; 57% of metastatic nodes were impalpable. Nodal metastases from gastric cardia tumours (6%) were more common than from the body (2%) or antrum (3%). Neck node metastases are uncommon in stomach cancer at presentation, are usually associated with extensive intra-abdominal metastatic spread, and adversely influence tumour staging in only a small minority of patients.

Detection of lymph node micrometastases in patients with squamous carcinoma of the head and neck

While the significance of large cervical node metastases in patients with head and neck squamous carcinomas is well established, the import of a finding of regional nodal micrometastases (where a micrometastasis is defined as a metastatic deposit greater than 0.2 mm and not greater than 2.0 mm in greatest dimension) or isolated tumor cells in those patients is less clearly understood. Some earlier investigators have suggested that finding micrometastases does not have an impact on prognosis; some later investigators, however, have taken issue with this position, arguing that finding either micrometastases or isolated tumor cells might portend a poorer prognosis for head and neck cancer patients. At this juncture, it is difficult to advance a single recommendation for handling a finding of micrometastases or isolated tumor cells. It would be helpful if two courses of action were followed: first, while the detection of micrometastases and isolated tumor cells remains an investigatory practice, data should be collected and analyzed with an eye to discerning whether such findings are indeed of significance to the individual head and neck cancer patient. Second, rigorous definitions of micrometastases and isolated tumor cells (such as the definitions suggested here) should be developed and widely employed so as to permit ready comparison between the results as they are reported by different investigators.

Micrometastases in cervical lymph nodes from patients with squamous carcinoma of the head and neck: should they be actively sought? Maybe

Techniques are now being developed, which allow ever smaller metastatic deposits in regional lymph nodes to be detected; the question is, should they be sought, or does their presence convey no additional information for treatment of head and neck carcinoma patients at this time? Preliminary findings have suggested that the presence of micrometastases may carry with it some prognostic information, and as a consequence, the search for micrometastases would, for the foreseeable future, appear to be a fertile ground for investigation. To bring some uniformity to this project, it is suggested that these definitions be adopted: a micrometastasis measures greater than 0.2 mm but less than 2.0 mm in diameter, and smaller deposits should be designated as isolated tumor cells, which, in turn, are subdivided into those isolated tumor cells detected by light microscopy, immunohistochemistry, or molecular methods. At this juncture, the import of such micrometastases remains in the realm of the clinical investigator--it remains an open question whether the identification of micrometastases (however they may ultimately come to be defined) will prove to have an impact on the care of head and neck cancer patients.

Neck dissection: then and now

The significance of metastatic disease in the lymph nodes of the neck as a critical independent prognostic factor in head and neck cancer has long been appreciated. Although 19th century surgeons attempted to remove involved cervical lymph nodes at the time of resection of the primary cancer, a systematic approach to en bloc removal of cervical lymph node disease, described in detail by Jawdyński in 1888 and popularized and illustrated by Crile in the early 20th century, provided consistent and more effective treatment, and forms the basis of our current techniques. During the first half of the 20th century, developments included preservation of the accessory nerve in selected cases, elective neck dissection performed in association with resection of various primary tumors, bilateral neck dissection and limited neck dissection. The greatest impetus to the status of radical neck dissection came from Martin, whose technique consisted of resection of all lymph nodes from level I-V together with the accessory nerve, internal jugular vein, sternocleidomastoid muscle and various other structures in a single block of resected tissue. Martin's technical precepts were followed until the latter part of the 20th century when modifications in technique began to find general acceptance. The first description of an effective technique of modified radical neck dissection was published in Spanish by Suárez, in 1963. This technique, which preserves important structures, such as the internal jugular vein, sternocleidomastoid muscle and accessory nerve, was refined and popularized by various authors who published their results in the English language literature during the period from 1964 through 1990 and beyond. Modified or "functional" neck dissection avoids much of the morbidity of radical neck dissection while achieving equivalent degrees of control of regional disease in properly selected cases. By the late 20th century, the concept of selective neck dissection, consisting of resection of only the nodal groups at greatest risk for metastasis from a given primary site, was studied and developed. These limited dissections are now widely employed for elective, and in properly selected cases, therapeutic treatment and staging of the neck, and have been proposed for limited cervical recurrences after various chemoradiation protocols. Prospective studies have demonstrated similar rates of neck recurrence and survival after elective selective neck dissection compared to elective modified radical neck dissection. Other modifications and factors applied to treatment of cervical lymph node disease include the use of adjuvant and neo-adjuvant radiation and chemotherapy, a revised system for classification of neck dissections, the identification of various adverse prognostic factors such as extracapsular spread and extranodal soft tissue deposits, application of sentinel lymph node biopsy to staging of the neck, the use of immunohistochemical and molecular techniques for identification of lymph node metastases not detectable by light microscopy, and the possibility of endoscopic neck dissection. The authors conclude that neck dissection, as evolved over the past century, is a fundamental tool in management of patients with head and neck cancer, but is still a work in progress.

Immunohistochemical analysis of negative inguinal lymph nodes in men with squamous cell carcinoma of the penis: are we missing micrometastases which could predict recurrence?

OBJECTIVE

To determine the presence or absence of micrometastases in lymph node dissection specimens of men with squamous cell carcinoma (SCC) of the penis using immunohistochemistry, and to correlate the results with clinical outcome.

PATIENTS AND METHODS

In all, 13 men (mean age 55.8 years) with penile SCC, treated at St George's hospital between 2001 and 2005, were selected. All had prophylactic lymph node dissections; (12 bilateral and one unilateral). All lymph nodes were negative on standard haematoxylin and eosin (H&E) staining. Each block was stained for cytokeratins MNF 116 and LP34. In all, 217 lymph nodes were examined (mean 16.7 per patient). The median (range) follow-up was 23 (10-52) months.

RESULTS

The mean tumour size and depth of invasion were 30.2 mm and 15.9 mm, respectively. There were eight T2 and four T3 tumours. Four tumours showed lymphovascular invasion. Information on tumour size and pathological grade was not available in one case. None of the patients have to date developed a local recurrence. A single lymph node was found to contain a micrometastasis, which was identified retrospectively on the original H&E slide. This measured 0.24 mm in maximum dimension. This patient had a T2G2 tumour with no vascular invasion; he has not progressed clinically in 10 months of follow-up.

CONCLUSIONS

Anticytokeratin immunohistochemistry on H&E-negative inguinal dissection specimens in men with SCC of the penis can detect micrometastases that might be overlooked on routine stains. Their prognostic and therapeutic significance needs further study.

Molecular assessment of neck dissections supports preserving level IIB lymph nodes in selective neck dissection for laryngeal squamous cell carcinoma with a clinically negative neck

OBJECTIVES

It was the aim of this study to determine whether level IIB lymph nodes can be saved in elective neck dissection as a treatment for patients with squamous cell carcinoma (SCC) of the larynx. We present a prospective analysis of a case series.

METHODS

Thirty-one patients with SCC of the larynx and without palpable lymph nodes at the neck who underwent an elective neck dissection were prospectively studied. The incidence of micrometastasis to level IIB lymph nodes after performing elective neck dissection was evaluated by nested reverse transcription polymerase chain reaction for cytokeratin (CK)19 and CK20 as well as by pathological examination.

RESULTS

Nested reverse transcription polymerase chain reaction for CK19 and CK20 mRNA presented similar results but differed from the pathological examination. Of the 31 patients, 6 (19%) by pathological analysis and 9 (29%) by molecular analysis had lymph nodes positive for metastatic SCC. By molecular analysis, only 1 of the 31 patients had involvement of level IIB lymph nodes.

CONCLUSIONS

This region may be preserved in elective neck dissection in patients with SCC of the larynx, so that accessory nerve dysfunction can be minimized and operative time can be saved.

Importance of molecular analysis in detecting cervical lymph node metastasis in head and neck squamous cell carcinoma

BACKGROUND

Because of the impact of nodal status on treatment and survival in squamous cell carcinoma of the head and neck, accurate staging of cervical lymph nodes is critical. This article explores the value of molecular analyses in the detection of cervical lymph node metastasis.

METHODS

A review of the literature was carried out and combined with our own experience regarding the role of molecular analyses in detecting cervical lymph node metastasis.

RESULTS

Few studies have demonstrated the diagnostic and prognostic relevance of molecular analysis in detecting tumor cells in lymph nodes. Nodal staging was improved by the use of molecular techniques; when compared with histopathologic examination, however, the small sample size of these studies did not allow definitive conclusions.

CONCLUSIONS

Molecular analysis is exquisitely sensitive in detecting very small cancer deposits within lymph nodes. It provides an oncologic basis that may be used to guide therapy and influence outcomes. It should be recommended for diagnostic use in controlled studies of patients without evidence of lymph node metastasis on routine hematoxylin-eosin-stained sections. The clinical significance of these types of metastases, however, must be determined with carefully designed and controlled prospective clinical trials.

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.

Management of the N0 neck--reference or preference

For patients with squamous cell carcinoma of the upper aerodigestive tract, appropriate management of the regional lymph nodes is an important and often controversial issue that has significant influence on survival. Over the years radical treatment either by surgery or radiotherapy contributed to improvement in prognosis. Recently, a more conservative approach has achieved a similar level of cancer control with less morbidity. This review considers the issues of selection of patients for treatment of the neck, choice of modality and extent of therapy, treatment of the contralateral neck, management of recurrence and influence of the site and status of the primary lesion.

New molecular diagnostic methods in head and neck cancer

Initial cancer evaluation includes assessment of histologic appearance, tumor grading, assessment of lymph node status, and presence of metastasis. However, traditional diagnostic methods such as histopathology and radiology are not sensitive enough to detect small numbers of cancer cells and are limited in their ability to predict response to treatment. Recently, there has been considerable progress in molecular diagnostics in these areas. Using molecular-based technologies, it is now possible to detect cancer early in asymptomatic individuals, identify minimal residual disease at histopathologic normal surgical margins, more precisely assess tumor burden in cancer patients, and more accurately assess the prognosis of the patients. Examples of these applications in the evaluation of head and neck cancer are reviewed here. However, despite the great promise of these new molecular approaches for cancer detection, much of the current technology limits their implementation into routine clinical use.