Challenging the need for random directed biopsies of the nasopharynx, pyriform sinus, and contralateral tonsil in the workup of unknown primary squamous cell carcinoma of the head and neck

Indications for oropharyngeal biopsy in head and neck squamous cell carcinoma of unknown primary: A systematic review (HNSCCUP)

INTRODUCTION

Patients presenting with head and neck squamous cell carcinoma of unknown primary (HNSCCUP) remain challenging clinical scenarios as large variation exists in practices used to locate the primary.

OBJECTIVE

The objective of this systematic review is to review of the literature and offer recommendations for oropharyngeal biopsies in HNSCCUP.

METHOD

Pubmed, Medline and Embase were searched to identify studies from inception to October 2021. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were followed.

RESULTS

A total of 483 articles were included and screened, 41 studies met the inclusion criteria, including over 3400 patients from the original articles (122 of these patients were reported on in two sequential articles by a single author - table 1) and 4 large metaanalyses including 1852 patients. The primary site identification rate following random biopsies or deep tissue biopsies is less than 5% in most studies. The mean detection rate following ipsilateral tonsillectomy is 34%; two pooled analyses indicate that the mean detection rate following tongue base mucosectomy is 64%, with this figure rising when the tonsils are negative.

CONCLUSIONS

High level evidence is lacking, with heterogeneity in the reported studies. Published meta-analyses are based on retrospective data. There is little evidence supporting the practice of random/non-directed oropharyngeal biopsies. Available evidence supports palatine tonsillectomy and tongue base mucosectomy compared to deep tissue biopsies.

[Cancer of unknown primary (CUP)-single-site, oligometastatic, and in the head and neck region]

INTRODUCTION

About 20% of all cancer of unknown primary (CUP) cases can be classified into favorable subgroups, which are defined by either obvious analogies to certain cancers with a known primary or amenability to local ablative treatment. In the updated European Society for Medical Oncology (ESMO) guidelines for diagnosis and treatment of CUP, the definition of favorable subgroups has been revised according to the latest scientific findings. In particular, the definition and treatment of oligometastatic CUP have undergone considerable changes in recent years. Thus, we delineate the current diagnostic and therapeutic standards for the two favorable CUP subtypes single-site/oligometastatic and head/neck CUP.

METHODS

The classification, diagnostic workup, and treatment of single-site and oligometastatic CUP are summarized based on the current ESMO and American Society of Clinical Oncology (ASCO) guidelines together with a literature review.

CONCLUSIONS

Single-site and oligometastatic CUP is defined by the presence of a maximum of five metastases that are amenable to local ablative treatment. Median overall survival is favorable and exceeds 4 years after local ablation of all detectable metastases. Lymph node metastases in the head and neck region represent a frequent scenario of single-site CUP. They usually originate from human papillomavirus (HPV)-associated squamous cell carcinoma in the oropharynx. Diagnostic workup comprises computed tomography (CT), magnetic resonance imaging (MRI) if necessary, and fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT), followed by panendoscopy and biopsies of suspicious mucosal sites. Neck dissection, potentially followed by adjuvant radiotherapy, and definitive radiotherapy represent equally effective oncological treatment options with respect to a favorable prognosis.

Role of Whole body PET/CT and Examination under anesthesia with multi-site biopsy in evaluating CUP

To evaluate the role of 18FDG-WBPET-CT, Examination under anesthesia (EUA), and multiple-site biopsy in detecting the occult site in head & neck carcinoma of unknown primary (HN-CUP). In this prospective study, 22 patients with diagnosed CUP, after a thorough outpatient endoscopic evaluation of upper airway and radiological evaluation (CT/MRI) that ruled out a primary lesion were included. These patients subsequently underwent whole-body PET-CT and EUA. Based on the presence of suspicious findings ( +) or their absence (-) on 18FDG-WBPET-CT (P) and EUA (E), we divided the patients into 5 groups: P-E-, P-E + , P + E-, P + E + , and P + or E + . All these patients underwent bilateral palatine tonsillectomy, bilateral nasopharyngeal biopsy, and ipsilateral lingual tonsillectomy for identification of occult primary. Out of 22 patients, the primary could be detected in 4 patients (18%) after the workup (three in the oropharynx and one in the hypopharynx, all ipsilateral). 18FDG-PET-CT suspected primaries in 7 patients; biopsy was positive for three (sensitivity-75%, specificity-77%, PPV-43%, NPV-93%). Out of 5 patients, who had suspicious findings on EUA, 3 of the biopsies revealed malignancy (sensitivity-75%, specificity-88%, PPV-60%, NPV-94%). Both PET-CT and EUA when combined, yield a NPV of 100% if both are negative and PPV of 100% when both are positive for suspicious findings. No primary was identified in the absence of a suspicion by PET-CT or EUA. Without a suspicion on 18FDG-WBPET-CT and EUA, there is a limited role of multiple-site biopsies in patients of HN-CUP.

Updates in the management of unknown primary of the head and neck

Squamous cell carcinoma (SCC) from an unknown primary tumor (SCCUP) accounts for 2.0%–5.0% of all head and neck cancers. SCCUP presents as enlarged cervical lymph nodes without evidence of a primary tumor upon physical examination. Primary site detection is important to target treatment and avoid treatment-related morbidity. In this review, we discuss updates in SCCUP management. Diagnostic workup should focus on localization of the primary tumor in SCCUP. Initial workup centers on neck biopsy to confirm the presence of SCC. Given the increasing incidence of HPV-related SCC in the oropharynx, HPV testing is crucial. An HPV-positive status can localize the tumor to the oropharynx, a common site for occult tumors. Imaging includes neck CT and/or MRI, and PET/CT. After imaging, panendoscopy, palatine tonsillectomy or diagnostic transoral robotic surgery can facilitate high rates of primary tumor localization. Primary tumor localization influences treatments administered. SCCUP has traditionally been treated aggressively with large treatment fields to all potential disease sites, which can induce weight loss and swallowing dysfunction. As a result, primary localization can reduce radiation fields and provide possible de-escalation to primary surgical management. Advances in intensity-modulated radiation therapy and dose management also have the potential to improve functional outcomes in SCCUP patients. Given the improved prognosis associated with HPV-positive SCCs, HPV tumor status may also inform future treatment de-intensification to reduce treatment-related toxicity.

Human Papillomavirus and Squamous Cell Carcinoma of Unknown Primary in the Head and Neck Region: A Comprehensive Review on Clinical Implications

Squamous cell carcinoma of unknown primary (SCCUP) is a challenging diagnostic subgroup of oropharyngeal squamous cell carcinoma (OPSCC). The incidence of SCCUP is increasing in parallel with the well-documented increase in OPSCC and is likewise driven by the increase in human papillomavirus (HPV). The SCCUP patient often presents with a cystic lymph node metastasis and undergoes an aggressive diagnostic and treatment program. Detection of HPV in cytologic specimens indicates an oropharyngeal primary tumor origin and can guide the further diagnostic strategy. Advances in diagnostic modalities, e.g., transoral robotic surgery and transoral laser microsurgery, have increased the successful identification of the primary tumor site in HPV-induced SCCUP, and this harbors a potential for de-escalation treatment and increased survival. This review provides an overview of HPV-induced SCCUP, diagnostic modalities, and treatment options.

Diagnostic approaches to carcinoma of unknown primary of the head and neck

Squamous cell carcinoma in cervical lymph nodes arising from an undetected primary tumour, termed carcinoma of unknown primary (SCCUP), is a well-recognized clinical presentation within head and neck oncology. SCCUP is a common presentation for patients with human papillomavirus-mediated oropharyngeal cancer (HPV + OPSCC), as patients with HPV + OPSCC often present with smaller primary tumours and early nodal metastasis. Meticulous work-up of the SCCUP patient is central to the management of these patients as identification of the primary site improves overall survival and allows for definitive oncologic resection or more focused radiation when indicated. This review summarizes the comprehensive diagnostic approach to the SCCUP patient, including history and physical examination, methods of biopsy of the cervical lymph node, imaging modalities and intraoperative methods to localize the unknown primary. Novel techniques such as transcervical ultrasound of the oropharynx, narrow band imaging and diagnostic transoral robotic surgery are also discussed.

Treatment of head and neck carcinoma of unknown primary: Cracking a nut with a sledgehammer?

OBJECTIVES

To compare the impact on survival and late radiation toxicity of patients with squamous cell carcinoma of unknown primary who were treated with ipsilateral neck dissection and ipsilateral postoperative radiotherapy (PORT) and patients treated with ipsilateral neck dissection and PORT to both sides of the neck plus the pharyngeal axis.

METHODS

Retrospective cohort study performed at the Erasmus University Medical Center in which 78 patients with squamous cell carcinoma of unknown primary were identified. Thirty-nine patients received PORT to both sides of the neck plus the pharyngeal axis (BILAX) and another 39 patients were irradiated on the ipsilateral neck (IPSI) only. The endpoints of the present study were 3-year overall survival (OS), 3-year disease-free survival (DFS), and overall late radiation toxicity.

RESULTS

The 3-year OS rate of the entire group of 78 patients was 74.2% and the 3-year DFS rate was 72.7%. The 3-year OS rates for the IPSI and the BILAX groups were 74.4% and 74.1%, respectively (P = .654). The most common late radiation toxicity experienced was xerostomia (64.8%), which was significantly more often seen in the BILAX group than in the IPSI group (83.8% and 44.1%, respectively, P = .001). Overall late radiation toxicity was significantly higher in the BILAX group (P = .003).

CONCLUSION

There was no significant difference in OS and DFS rates between the IPSI and the BILAX group. Late radiation toxicity was significantly higher in the BILAX group.

LEVEL OF EVIDENCE

Level 2b: Individual retrospective cohort study.

Metastatic Squamous Cell Carcinoma to the Cervical Lymph Nodes From an Unknown Primary Cancer: Management in the HPV Era

Background

Patients with metastases in the lymph nodes of the neck and no obvious primary tumor, neck cancer with unknown primary (NCUP), represent a management challenge. A majority of patients have metastatic squamous cell carcinoma (SCC), although other histologies do occur.

Methods

We comprehensively reviewed the literature, compared available guidelines, and conferred with an international team of experts.

Results

Positron emission tomography-computed tomography (PET-CT) and fine needle aspiration (FNA) under ultrasound guidance increase accuracy of diagnosis. Immunohistochemistry (IHC), determination of human papilloma virus (HPV) status, by p16 staining or by in situ hybridization (ISH), and next-generation gene sequencing can guide us regarding probable primary sites and tumor biology. Narrow Band Imaging (NBI) has been introduced for the early detection of subtle mucosal lesions. Direct laryngoscopy (DL) and tonsillectomy have long been procedures used in the search for a primary site. More recently, TransOral Robotic Surgery (TORS) or Transoral LASER Microsurgery (TLM) have been introduced for lingual tonsillectomy.

Conclusions

New technologies have been developed which can better detect, diagnose, and treat occult primary tumors. Decisions regarding therapy are based on the primary tumor site (if discovered) and N stage. Options include neck dissection with or without postoperative adjuvant therapy, primary irradiation, or combined chemotherapy with irradiation. The preferred treatment of patients whose primary remains unidentified is controversial.

Diagnosis and Management of Squamous Cell Carcinoma of Unknown Primary in the Head and Neck: ASCO Guideline

PURPOSE

To provide evidence-based recommendations to practicing physicians and other health care providers on the diagnosis and management of squamous cell carcinoma of unknown primary in the head and neck (SCCUP).

METHODS

The American Society of Clinical Oncology convened an Expert Panel of medical oncology, surgery, radiation oncology, radiology, pathology, and advocacy experts to conduct a literature search, which included systematic reviews, meta-analyses, randomized controlled trials, and prospective and retrospective comparative observational studies published from 2008 through 2019. Outcomes of interest included survival, local and regional disease control, and quality of life. Expert Panel members used available evidence and informal consensus to develop evidence-based guideline recommendations.

RESULTS

The literature search identified 100 relevant studies to inform the evidence base for this guideline. Four main clinical questions were addressed, which included subquestions on preoperative evaluations, surgical diagnostic and therapeutic procedures, appropriate pathology techniques, and adjuvant therapy.

RECOMMENDATIONS

Evidence-based recommendations were developed to address preoperative evaluation for patients with a neck mass, surgical diagnostic and therapeutic procedures, appropriate treatment options in unilateral versus bilateral SCCUP.Additional information is available at www.asco.org/head-neck-cancer-guidelines.

Evaluation of radiation treatment volumes for unknown primaries of the head and neck in the era of FDG PET

Objectives

Positron-emission tomography (PET) has improved identification of the primary tumor as well as occult nodal burden in cancer of the head and neck. Nevertheless, there are still patients where the primary tumor cannot be located. In these situations, the standard of care is comprehensive head and neck radiation therapy however it is unclear whether this is necessary. This study examines the effects of radiation treatment volume on outcomes among using data from two cancer centers in unknown primary carcinoma of the head and neck.

Methods

Patients received unilateral (n = 34), or bilateral radiation (n = 28). Patient factors such as age, gender, smoking history, and patterns of failure were compared using Mann Whitney U and Chi Square. Overall survival (OS) and disease free survival (DFS) trends were estimated using Kaplan-Meier survival curves. Effect of treatment volume on survival was examined using multivariate cox proportional hazard regression model.

Results

No significant differences were observed in the frequency of local (p = 0.32), regional (p = 0.50), or distant (p = 0.76) failures between unilateral and bilateral radiation therapy. By Kaplan-Meier estimates, OS (3-year OS bilateral = 71.67%, unilateral = 77.90%, p = 0.50) and DFS (3-year DFS bilateral = 77.92%, unilateral = 69.43%, p = 0.63) were similar between the two treatment approaches. Lastly, multivariate analysis did not demonstrate any significant differences in outcome by treatment volumes (OS: HR = 0.74, 95% CI: 0.31, 1.81, p = 0.51; DFS: HR: 0.68, 95% CI: 0.24, 1.93, p = 0.47).

Conclusions

Unilateral radiation therapy compared with bilateral produced similar survival.

Tongue base mucosectomy for carcinoma of unknown primary using endoscopic electrocautery: rationale for wider implementation of an institutionally restricted technique

BACKGROUND

Cervical metastasis from an unknown primary site invariably results in pan-mucosal irradiation if a primary tumour is not identified. Transoral robotic and laser-assisted mucosectomy are valid techniques to increase diagnostic rates, but these remain restricted to certain centres. This paper describes, in detail, a technique in which mucosectomy is performed via endoscopic electrocautery.

METHODS

Patients were prospectively recruited between May 2017 and June 2018. Inclusion criteria stipulated biopsy-proven metastatic cervical squamous cell carcinoma, with negative findings on magnetic resonance imaging and positron emission tomography/computed tomography, in addition to examination under anaesthetic, tonsillectomy and 'blind' tongue base biopsies without tumour identification, prior to mucosectomy.

RESULTS

Of nine patients, a mucosal primary was identified in four (44.4 per cent), for which ipsilateral intensity-modulated radiotherapy was advocated in three and completion tongue base resection in the fourth. Dysplasia was demonstrated in two further patients, which provided information relevant to radiotherapy fields and post-treatment surveillance. No surgical complications were identified.

CONCLUSION

Tongue base mucosectomy using electrocautery and conventional tonsillectomy equipment is a safe, effective technique in the identification of cervical metastasis from an unknown primary site. It expands the potential breadth of use, quickens prolonged diagnostic pathways and obviates the necessity for pan-mucosal irradiation.

An evaluation of the diagnostic methods in head and neck cancer of unknown primary site

BACKGROUND

Various detection methods to identify the primary in head and neck cancer of unknown primary (HN-CUP) require evaluation to improve and standardize management.

OBJECTIVES

To evaluate the use of different diagnostic methods, which aim at decreasing the incidence of HN-CUP.

MATERIAL AND METHODS

We conducted a retrospective analysis of patients with HN-CUP at the Helsinki University Hospital during 1995-2011. We evaluated clinical assessment, definitive treatment, histopathology, and follow up. We analyzed the success in identifying the primary site to show any changes in diagnostic methods over time.

RESULTS

Frequency of HN-CUP and success in identifying the primary site have remained constant despite the addition of PET-CT and determination of human papilloma virus (HPV) status in diagnostics. Among 133 patients, the diagnostic work up identified the primary site in 53% and the oropharynx predominated (69%). This left 85 patients with HN-CUP and 5-year overall and disease-free survival rates were 71 and 69%, respectively.

CONCLUSIONS

Panendoscopy including tonsillectomy should not be omitted in the work up.

SIGNIFICANCE

We demonstrate a steady frequency of HN-CUP and constant success in identifying the primary site. Detection of a primary later in the follow up did not impact the survival.

[Advances in the management of cervical lymphadenopathies of unknown primary: advances in diagnostic imaging and surgical modalities and new international staging system]

INTRODUCTION

Cervical lymphadenopathies of unknown primary represent 3 % of head and neck cancers. Their diagnostic work up has largely changed in recent years. This review provides an update on diagnostic developments and their potential therapeutic impact.

MATERIALS AND METHODS

This is a systematic review of the literature.

RESULTS

In recent years, changes in epidemiology-based prognostic factors such as human papilloma virus (HPV) cancers, advances in imaging and minimally invasive surgery have been integrated in the management of cervical lymphadenopathies of unknown primary. In particular, systematic use of PET scanner and increasing practice of robotic or laser surgery have contributed to increasing detection rate of primary cancers. These allow more adapted and personalized treatments. The impact of changes in the eighth TNM staging system is discussed.

CONCLUSION

The management of cervical lymphadenopathies of unknown primary cancer has changed significantly in the last 10 years. On the other hand, practice changes will have to be assessed.

Synchronous bilateral tonsil carcinoma: case presentation and review of the literature

Background

The incidence of synchronous bilateral tonsil carcinoma seems to be underreported. For adequate oncologic treatment, it is mandatory to remove all primaries to prevent recurrence or metachronic disease. The purpose of this manuscript is to provide a comprehensive review on this topic and to emphasize the need of bilateral tonsillectomy in cases of cancer of unknown primary (CUP) as well as in the case of a unilateral tonsillar carcinoma.

Material and methods

A systematic review of the literature was performed for “bilateral tonsillar neoplasm”, “synchronous cancer of the oropharynx” and “cancer of unknown primary in head and neck”.

Results

We present a clinical case with bilateral tonsillar carcinoma in initially suggested cancer of unknown primary. Clinically, both tonsillar sites were unsuspicious, but in PET/CT an ipsilateral enhancement of the tonsil area was detected. The pathological work up of bilateral tonsillectomy specimens revealed bilateral squamous cell carcinoma with HPV-type 16 positivity. The review of the literature revealed 29 cases of bilateral tonsil cancer.

Conclusion

The handling of tonsillar tissue in the frame of panendoscopy in the case of CUP is still controversial. We recommend a bilateral tonsillectomy as a routine procedure for cancer of unknown primary as well as unilateral tonsillar carcinoma. Herewith the detrimental consequences of occult metachronous contralateral tonsillar carcinoma can be prevented.