Approach to metastatic carcinoma of unknown primary in the head and neck: squamous cell carcinoma and beyond

Metastatic cutaneous squamous cell carcinoma accounts for nearly all squamous cell carcinomas of the parotid gland

Primary squamous cell carcinoma of the parotid gland (pSCCP) has long been recognized as a separate entity and is included in the WHO classifications of salivary gland tumors. However, it is widely accepted among head and neck pathologists that pSCCP is exceptionally rare. Yet, there are many publications describing series of pSCCP and data from SEER and other cancer register databases indicate erroneously an increasing incidence of pSCCP. Importantly, pSCCP and metastatic (secondary) squamous cell carcinoma to the parotid gland (mSCCP) have nearly identical histological features, and the diagnosis of pSCCP should only be made after the exclusion of mSCCP. Moreover, all of the histological diagnostic criteria proposed to be in favor of pSCCP (such as, for example, dysplasia of ductal epithelium) can be encountered in unequivocal mSCCP, thereby representing secondary growth along preexistent ducts. Squamous cell differentiation has also been reported in rare genetically defined primary parotid carcinomas, either as unequivocal histological squamous features (e.g., NUT carcinoma, mucoepidermoid carcinoma), by immunohistochemistry (e.g., in NUT carcinoma, adamantinoma-like Ewing sarcoma, basal-type salivary duct carcinoma, mucoepidermoid carcinoma), or a combination of both. Another major issue in this context is that the International Classification of Diseases (ICD) coding system does not distinguish between primary or metastatic disease, resulting in a large number of patients with mSCCP being misclassified as pSCCP. Immunohistochemistry and new molecular biomarkers have significantly improved the accuracy of the diagnosis of many salivary gland neoplasms, but until recently there were no biomarkers that can accurately distinguish between mSCCP and pSCCP. However, recent genomic profiling studies have unequivocally demonstrated that almost all SCCP analyzed to date have an ultraviolet light (UV)-induced mutational signature typical of mSCCP of skin origin. Thus, mutational signature analysis can be a very useful tool in determining the cutaneous origin of these tumors. Additional molecular studies may shed new light on this old diagnostic and clinical problem. This review presents a critical view of head and neck experts on this topic.

Head and Neck Cancer of Unknown Primary: A Multicenter Retrospective Cohort study in Northern Thailand, an Endemic Nasopharyngeal Cancer Area

OBJECTIVE

This study aimed to evaluate the characteristics and oncological outcomes of head and neck carcinoma of unknown primary (HNCUP) patients in an endemic nasopharyngeal cancer (NPC) area.

METHODS

One hundred and forty-four HNCUP patients curatively treated between January 1995 and December 2022 from 5 centers were retrospectively recruited onto the study to analyze the clinicopathological characteristics and oncological outcomes and compare them with historical data. A multivariate Cox proportional hazards model analysis was performed to evaluate factors affecting survival outcomes. A propensity-matched pair analysis of the patients with positive and negative EBV-encoded small RNA (EBER) staining was applied to compare the characteristics and outcomes between the two groups.

RESULTS

The median follow-up time was 45 months. Most patients (88.2%) received total mucosal irradiation (TMI). Primary tumor emergence (PTE) was detected in 6 patients (4.2%) who did not have TMI. The 5-year overall survival (OS), disease-free survival, and locoregional recurrence-free survival were 51.3%, 64.9%, and 72.7%, respectively. Extranodal extension and N3 compared with the N1 stage were the significant independent predictors for OS (HR 2.90, 95% CI 1.12-7.51, p = 0.028 and HR 3.66, 95%CI 1.23-11.89, p = 0.031, respectively). The matched-pair analysis demonstrated comparable all survival outcomes between the EBER-positive and -negative groups. All patients in the matched pair analysis received TMI, and no PTE was detected.

CONCLUSION

Our survival outcomes were comparable to previous studies with a low rate of PTE. The matched pair analysis of EBER-positive and -negative groups revealed similar oncological outcomes and no primary tumor emergence when total mucosal irradiation was administered.

Intrathyroidal metastasis of tonsillar squamous cell carcinoma masquerading as a primary thyroid tumor

Intrathyroidal metastasis of tonsillar squamous cell carcinoma is rare. To date, only six cases have been reported in the literature. This case was unusual and presented with thyromegaly before the diagnosis of the primary tumor. A 55-year-old male patient was suspected to have a primary thyroid tumor with nodal metastasis. The thyroid gland was diffusely enlarged, with no discernible mass. Histologically, the thyroid parenchyma revealed extensive endolymphatic tumor emboli, which were positive for p40 and p16 in a background of chronic lymphocytic thyroiditis. Positron emission tomography-computed tomography revealed hypermetabolic activity in the right tonsillar region. Tonsillar biopsy revealed human papillomavirus-positive squamous cell carcinoma. The present case is the first reported case of intrathyroidal metastasis of tonsillar squamous cell carcinoma with an initial clinical presentation of thyroid enlargement before the primary tumor of tonsillar cancer was diagnosed.

Cutaneous squamous cell carcinoma with secondary parotid metastasis: a case report

Background

Majority of cutaneous squamous cell carcinoma (cSCC) originate in the head and neck region, with 1-3% have been found to have parotid or periparotid lymph nodes metastases. The significance of secondary parotid metastases from cSCC lies in its propensity of cervical lymph node spread and distant metastases leading to a dismal prognosis, and therefore the importance of early diagnosis and prompt treatment.

Case Description

An 85-year-old gentleman with prior history of right temporal squamous cell carcinoma (SCC) presented with a new onset left cheek cSCC. He underwent complete excision with clear margin. Four months following initial surgery, he developed ulcerative mass at left angle of mandible. CT scan revealed an underlying left parotid gland tumor, which was confirmed to be SCC by fine needle aspiration cytology (FNAC). He was then surgically treated with nerve-sparing total parotidectomy, modified radical neck dissection, soft tissue reconstruction using free anterolateral thigh fasciocutaneous flap and adjuvant radiotherapy with satisfactory outcomes.

Conclusions

Although rare, metastatic cutaneous SCC to parotid gland represents a unique group of locally advanced cutaneous SCC. Multimodal treatment approach consisting of total parotidectomy, ipsilateral neck dissection and adjuvant radiotherapy has been shown to improve the locoregional control of the disease and limit the propensity to distant metastasis.

A Rare Case of Aggressive Atypical Cervical Cancer With Multi-Organ Involvement

Squamous cell carcinoma (SCC) of cervical origin with metastasis to the brain is rare. Our patient was a 30-year-old Caucasian female with squamous cell carcinoma, initially with unknown primary, with metastases to the brain, kidney, cervix, lung, adrenal glands, vulva, pelvic wall, and scalp. She initially presented to her outpatient gynecologist for a vulvar mass. A biopsy of the vulvar mass was consistent with SCC. The patient continued to have fatigue along with thoracic rib pain. An initial work-up was performed, including imaging which showed diffuse metastatic disease involving the lungs, kidneys and adrenal glands, as well as a pathological compression fracture of the seventh thoracic vertebra with cord compression. Brain magnetic resonance imaging (MRI) showed multiple metastatic lesions and she underwent craniotomy for brain lesion resection. Given the aggressive nature of the patient's disease and her symptomatic burden, she was started on chemotherapy in the hospital with Carboplatin, Paclitaxel, and Pembrolizumab.

Cervical squamous cell carcinoma of unknown primary: Oncological outcomes and prognostic factors

BACKGROUND/OBJECTIVES

Cervical squamous cell carcinoma of unknown primary (SCCUP) is a rare entity within head and neck cancer and both treatment regimens as well as identified potential predictors for oncological outcomes vary between published series. In this study, we evaluated oncological outcomes and identified potential prognostic factors for outcome.

PATIENTS AND METHODS

This retrospective monocentric cohort study includes 82 SCCUP patients diagnosed and treated between January 2000 and June 2021. Overall survival (OS), disease-specific survival (DSS), disease-free survival (DFS) and locoregional recurrence-free survival (LRFS) were evaluated. The Cox proportional hazards model was used to analyze the prognostic effect of patient and tumor characteristics on oncological outcomes.

RESULTS

Five year OS, DSS, DFS and LRFS were respectively 53.9%, 72.2%, 68.9% and 67.3%. The p16 status was evaluated in 55 patients with 40% being p16 positive. On univariable analysis, p16 negative SCCUPs had significantly worse survival and recurrence rates in the presence of clinical extranodal extension (cENE) (OS: p=0.0013, DSS: p=0.0099, DFS: p=0.0164, LRFS: p=0.0099) and radiological extranodal extension (rENE) (OS: p=0.0034, DSS: p=0.0137, DFS: p=0.0167, LRFS: p=0.0100). In p16 positive SCCUP patients, rENE had a significantly negative prognostic effect on DFS (p=0.0345) and LRFS (p=0.0367). Total group multivariate analysis identified rENE as an independent negative predictor for all oncological outcomes. The "number of positive lymph nodes" was a second independent predictor for DSS (p=0.0257) and DFS (p=0.0435).

CONCLUSIONS

We report favorable oncological outcomes, comparable to previously published results. Although the presence of rENE seems associated with poor oncological outcomes, the differential effect of clinical, radiological and pathological ENE in both p16 positive and negative subgroups remain to be elucidated by further prospective research.

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.

A Systematic Review of Cancer of Unknown Primary in the Head and Neck Region

Background

Despite the vivid progress in molecular and genetic profiling, extensive diagnosis and multiple therapeutic modalities, cancers of unknown primary in the head and neck region continue to be a formidable challenge.

Aim

The purpose of the review is to present the most recent and well-established findings concerning cancers of unknown primary (CUPs) in the head and neck patients and consequently to provide medical specialists with essential information regarding the biology, pathology, histology, diagnosis and treatment of CUP in the head and neck region.

Material and Methods

The Medline/PubMed database was searched by using the following keywords “CUP”, “cancer of unknown primary”, “CUP biology”, “head and neck”. The references of the publications of interest were also screened for relevant papers. There were no limitations in regard to the publication date.

Conclusion

Unique biology and pathophysiology prompt the management of CUP to be demanding. The vivid rise in HPV-related CUPs during the last 20 years has put more focus on this phenomenon. New findings concerning the enigmatic biology of CUP provide fundaments for targeted therapy. Despite the availability of various diagnostic methods, the diagnosis of CUP continues to be a time-consuming, strenuous process that eventually provides answers. It remains controversial as to what combination of treatment methods is the most effective. There is no consensus on the value of combining chemotherapy with radiotherapy. Highly specific surgical treatments for particular histological types of CUP produce more satisfactory results. It is paramount to establish reliable guidelines concerning the diagnosis and treatment of CUP patients.

An Unusual Case of Biliary Obstruction Because of Human Papillomavirus-Associated Metastatic Squamous Cell Carcinoma From Head and Neck Primary

Secondary pancreatic tumors are uncommon, with the majority originating from primary gastrointestinal or lung cancers. We present the case of a 42-year-old woman with squamous cell carcinoma of the pancreas, found to be human papillomavirus–positive on in situ hybridization. After extensive work-up, the patient was determined to have a previously undiagnosed, asymptomatic head and neck primary malignancy. There is sparse literature discussing metastatic human papillomavirus–positive squamous cell carcinoma to the pancreas. This report highlights the importance of including this diagnosis when considering a differential for secondary pancreatic tumors, especially squamous etiology.

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.

Image-guided lymph node fine-needle aspiration: the Johns Hopkins Hospital experience

INTRODUCTION

Although the diagnostic utility of lymph node fine-needle aspiration (FNA) is well established in the evaluation of metastatic malignancy, its value in the diagnosis of lymphoma is more controversial; yet, there is a growing trend among practitioners towards less-invasive procedures such as FNA and core needle biopsy (CNB). The guidelines recently published by the American Society for Clinical Pathology/College of American Pathology (CAP) regarding the workup of lymphoma include recommendations on the value and limitations of FNA.

MATERIALS AND METHODS

We reviewed 1237 image-guided lymph node aspirates from 695 procedures (410 nodes from 360 ultrasound [US]-guided cases, 799 from 309 endobronchial ultrasound [EBUS], 25 from 23 endoscopic ultrasound [EUS], and 3 from 3 computed tomography [CT]).

RESULTS

The majority (40 of 46, 87%) of lymph nodes suspected of lymphomatous involvement were aspirated under ultrasound. Core needle biopsy [CNB] was obtained for 41 (89%) lymph nodes, including all 40 US specimens. Flow cytometry (FC) was performed on 37 (80%) aspirates; aspirates without FC were from patients who had a history of Hodgkin lymphoma, or showed granulomata or non-hematologic malignancy onsite. Thirty-one (67%) lymph nodes were sent for review by hematopathology. Forty-two (91%) lymph node FNA/CNB yielded actionable diagnoses. Seventeen of 241(7%) cases aspirated for other indications (14 US, 3 EBUS) were involved by a lymphoproliferative process. All were reviewed by hematopathology. All 14 US cases had FC and CNB.

CONCLUSION

Our institutional approach towards lymph node cytopathology for lymphoma workup appears to be in accordance with the new CAP guidelines, and demonstrates a potential triage and workflow model for lymph node FNA specimens that allows for accurate diagnosis in cases where lymphoma is a consideration.

Carcinoma of Unknown Primary and the 8th Edition TNM Classification for Head and Neck Cancer

OBJECTIVE

In the 8th Edition TNM Classification for Head and Neck Cancer, the classification for carcinoma of unknown primary (CUP) changed in addition to oropharyngeal carcinomas. The current classification considers extranodal extension (ENE), determination of p16 (surrogate marker for human papillomavirus), and detection of Epstein-Barr virus (EBV). The aim of this study was to investigate the influence of the new classification on the prognosis of p16-positive and p16-negative CUP and the impact of EBV proof.

METHODS

Clinical and pathological data from patients with CUP of the head and neck between 2009 and 2018 were evaluated. The 7th (UICC7) and 8th (UICC8) edition of the Union for International Cancer Control staging system were applied and compared.

RESULTS

There were 97 patients treated, 26.8% women and 73.2% men. The average age at initial diagnosis was 64.6 years. Of which, 58.8% had a documented history of smoking, 37.1% were positive for p16, 4.1% were positive for EBV, and 66% had ENE. Most of the patients were at stage III/IVa (78.4% according to UICC7). According to UICC8, p16+ patients were mainly at stage I (86.1%), and p16- at stage IVb (56.1%). P16 status (P = .002), ENE (P = .001), nodal category (TNM7, P < .001), UICC stage (TNM7, P < .001) and UICC stage (TNM8, P < .001) had a significant impact on survival in the univariate analysis. The 8th TNM classification resulted in a downstaging of p16-positive CUP syndromes and an upstaging of p16-negative syndromes.

CONCLUSION

The 8th TNM classification shows the lower UICC stage in p16-positive CUP syndromes. The prognostic significance for survival has improved from the 7th to the 8th TNM classification. LEVEL OF EVIDENCE USING THE 2011 OCEBM: Level 3. Laryngoscope, 131:E2534-E2542, 2021.

Proceedings of the North American Society of Head and Neck Pathology, Baltimore, MD, March 17, 2021: The Mistakes I Made When I Stepped Out of My Neck of the Woods

Rapidly growing, symptomatic, non-hematological, malignant neck masses are unusual in young adults. We report a case of a 34-year-old African American male with sickle cell trait who presented with a large left supraclavicular/cervical mass comprising of poorly differentiated malignant epithelial cells consistent with metastatic carcinoma of unknown origin. Upon immunohistochemistry, the tumor showed loss of INI1 (BAF47) and retained PAX-8 expression. After extensive clinical and radiological work-up the primary tumor was found to be a 2.6 cm renal medullary carcinoma. This case highlights the role of multidisciplinary approach to the diagnosis of a neck mass and to understanding that certain genetically-defined tumors can occur at and metastasize to any site.

Quantitative assessment of p16 expression in FNA specimens from head and neck squamous cell carcinoma and correlation with HPV status

BACKGROUND

This study investigated p16 by immunohistochemistry (IHC) on cellblocks (CBs) and human papillomavirus (HPV) by polymerase chain reaction (PCR) in fine-needle aspiration (FNA) of head and neck squamous cell carcinoma (HNSCC).

METHODS

Receiver operating characteristic (ROC) curve analysis was used to assess test performance in CBs compared with p16 IHC in 42 surgical specimens from patients with HNSCC and in correlation with HPV by PCR in cytology specimens. The study assessed HPV by PCR in FNA specimens as a substitute for p16 IHC in surgical specimens.

RESULTS

Of 42 cases, 38 CBs showed malignant cells as cohesive clusters of viable cells with or without single tumor cells, whereas 4 specimens were composed exclusively of single tumor cells and degenerated cells. All p16-negative surgical specimens showed an absence of p16 staining in the corresponding CBs (n = 16). In the p16-positive surgical cases (n = 26), corresponding CBs with tumor clusters (n = 23) showed heterogeneous p16 expression ranging from 40% to 100%; however, scoring single cells was challenging and unreliable because of cellular degradation. ROC curve inspection showed the optimal threshold to be at least 40% p16 staining in tumor clusters with 100% sensitivity and specificity. In cases with inadequate CBs, HPV by PCR on needle rinse showed 88% sensitivity and 100% specificity for p16 expression in surgical specimens.

CONCLUSIONS

A cutoff of at least 40% p16 expression in tumor clusters may be appropriate for p16 positivity in cytology CB specimens. A positive HPV finding by PCR on needle rinse can be used as a substitute for p16 expression in surgical specimens.

PET/CT in Surgical Planning for Head and Neck Cancer

Fluorine-18 (¹⁸F)-fluorodeoxyglucose (FDG) positron emission tomography fused with computed tomography (PET/CT) is a valuable tool in surgical planning for head and neck squamous cell carcinoma (HNSCC). If performed prior to biopsy or other surgical intervention, FDG-PET/CT has high sensitivity for the detection of the primary site in patients with cervical lymph node metastases from unknown primary origin and can be used to direct the surgical workup. FDG-PET/CT is superior to CT alone for detection of nodal metastases outside the expected pattern or distant metastases or second primary cancers and can greatly affect determination of appropriate management including surgical eligibility. Prior to the advent of PET/CT, many patients undergoing (chemo)radiation-based therapy had planned post-treatment neck dissection; FDG-PET/CT now has a proven role in the evaluation of recurrent or persistent disease amenable to salvage surgery and enables safe avoidance of planned postradiation neck dissection with a high negative predictive value. Specifically for this important application, two standardized reporting metrics may be used in the head and neck anatomic region: the "Hopkins criteria" and the "Neck Imaging Reporting and Data System"; both systems produce a formalized evaluation and recommendation based on PET/CT findings. The role of PET/CT as a replacement for elective neck dissection or examination under anesthesia remains controversial but deserves further study. FDG-PET/CT has a wide-ranging impact on the surgical management of patients with HNSCC and should be used routinely in patients with unknown primary nodal disease and those presenting with advanced-stage cancers at initial staging and to assess treatment response.

The Evolution of Care of Cancers of the Head and Neck Region: State of the Science in 2020

Cancers that arise in the head and neck region are comprised of a heterogeneous group of malignancies that include carcinogen- and human papillomavirus (HPV)-driven mucosal squamous cell carcinoma as well as skin cancers such as cutaneous squamous cell carcinoma, basal cell carcinoma, melanoma, and Merkel cell carcinoma. These malignancies develop in critical areas for eating, talking, and breathing and are associated with substantial morbidity and mortality despite advances in treatment. Understanding of advances in the management of these various cancers is important for all multidisciplinary providers who care for patients across the cancer care continuum. Additionally, the recent Coronavirus Disease 2019 (COVID-19) pandemic has necessitated adaptations to head and neck cancer care to accommodate the mitigation of COVID-19 risk and ensure timely treatment. This review explores advances in diagnostic criteria, prognostic factors, and management for subsites including head and neck squamous cell carcinoma and the various forms of skin cancer (basal cell carcinoma, cutaneous squamous cell carcinoma, Merkel cell carcinoma, and melanoma). Then, this review summarizes emerging developments in immunotherapy, radiation therapy, cancer survivorship, and the delivery of care during the COVID-19 era.

A systematic review on Transoral robotic surgery (TORS) for carcinoma of unknown primary origin: Has tongue base mucosectomy become indispensable?

Background

Transoral robotic surgery (TORS) is increasingly used in head and neck surgery and in carcinoma of unknown primary (CUP) origin specifically. Due to the rising incidence of human papillomavirus (HPV)‐related oropharyngeal squamous cell carcinoma (OPSCC), there is a rationale for finding ways to de‐escalate treatment strategies. This review aims to test the hypothesis that TORS is a meaningful adjunct in the diagnostic (and therapeutic) pathway in CUP in head and neck.

Methods

A structured search of the literature was performed with the search terms ‘TORS’ and ‘Carcinoma of Unknown Primary’.

Results

Two hundred and seventy four cases of CUP in which TORS was used were identified for further analysis. Workup for CUP was comparable in all series with regard to physical examination, fine and/or gross needle examination of cervical nodes, fibre optic endoscopy, imaging and robot assisted mucosectomy of the base of tongue (BOT). Identification rate of the primary tumour was 72% on average (range 17%‐ 90%), and 55%‐ 96% were HPV positive. Clear margins were achieved in 60% (range 0%‐85%) of resected occult tumours. Complication rate of TORS BOT mucosectomy was low with mainly grade I‐III sequelae according to Clavien–Dindo.

Conclusions

Transoral robotic surgery seems to be a useful and safe adjunct in the diagnostic and therapeutic pathway in case of CUP in an era of increasing incidence of HPV‐positive OPSCC.

Histopathological Analysis of Metastatic Tumours of the Oral Cavity with Example of Metastatic Renal Cell Carcinoma to Tongue

Background/Aim: Metastatic tumours make up only 1-3% of all malignant tumours of the oral region; however, in 25% of the total number of cases, they are the first sign of the disease. Usually, metastases in the oral region are followed by poor prognosis. Metastases are more common in the mandible than in the maxilla; in soft tissues, they most commonly occur in the attached gingiva and tongue. Malignant tumours of the lung, breast, kidney, liver, bone, prostate, thyroid gland, skin, colon and female genital organs most commonly give metastases in this region, usually in patients aged 40 to 70 years.

Case Report: We present a patient aged 79 years with a tumour change in the body of the tongue. After histopathological and immunohistochemical analysis (Cytokeratin, Vimentin, CD 10 positive tumour cells, Cytokeratin 7, Cytokeratin 20 negative tumour cells), there was a suspicion of metastasis of clear cell renal carcinoma (CCRC). Due to renal cancer, the patient had left kidney operated seven years before the diagnosis of tongue tumour.

Conclusions: Diagnosis of metastatic tumours of the oral region is a great challenge, both for clinicians and for histopathologists. Since it is a heterogeneous group of neoplasms, standard histopathological tissue processing, is not always sufficient to determine the histological type of tumour and its primary origin. In the analysis of metastatic tumours of the oral region, team work is important and careful clinical and histopathological assessment lead to definitive and accurate diagnosis.

Carcinoma of unknown primary abuts left clavicle: Case report and review of the literature

•

Carcinoma of unknown primary clinical manifestations usually associated with head and neck region.

•

Painless cervical Lymphadenopathy is the most common symptom of the disease.

•

Laboratory tests usually do not identify the primary disease.

•

Limited data exists about management and the role of surgery in carcinoma of unknown primary if a single neck mass exists without evidence of lymph node implication.

Introduction

Carcinoma of unknown primary is a well-recognized clinical syndrome which accounts for the 3–5% of all the malignancies. Patients with carcinoma of unknown primary usually present with late stage disease without having identified the primary source of the tumour despite an extensive diagnostic work-up.

Presentation of case

A 60 years old male presented to the clinic complaining of a neck mass to the left lateral neck. Patient’s history was unremarkable without evidence of any malignant disease. Clinical and radiological examination revealed a cystic mass extending from the lower one third of the neck to the left clavicle causing periostal reaction. Mass biopsy and PET-CT was unspecific for the primary origin of the mass. However in the context of tumour immunohistochemistry, HPV status, neck location and basaloid cell differentiation, the tumour mass was considered as carcinoma of unknown primary with possible oropharyngeal primary location. The patient underwent surgical resection of the mass, left clavicle and the first rib. One year after the operation the patient is disease free.

Discussion

Although CUP usually presents with cervical lyphadenopathy, in our case there was no evidence of lymph node tissue infiltration in the neck region. Surgical resection of the mass showed that the location was extending within the cervical soft tissues and upper thorax. Taking into consideration the absence of lymphadenopathy this is an uncommon location of carcinoma of unknown primary in the neck.

Conclusion

This is an uncommon location of CUP with possible implications in survival and management.

Pharyngeal-sparing radiation for head and neck carcinoma of unknown primary following TORS assisted work-up

OBJECTIVE

In patients with head and neck carcinoma of unknown primary (HNCUP;pT0) following TORS-assisted workup, we have adopted a pharyngeal-sparing radiation therapy (PSRT) approach targeting only the at-risk neck and omitting treatment of the pharynx. We report outcomes following PSRT, and compare to institutional historical control subjects who received pharyngeal-targeted RT (PRT).

METHODS

Between 2009 and 2018, 172 patients underwent TORS-assisted endoscopy as part of their workup for HNCUP. Following TORS, 54 patients had pT0 disease, of which 45 received RT. Forty-nine percent received PSRT and 51% received PRT.

RESULTS

No statistically significant differences existed between the PSRT and PRT groups with respect to overall nodal distribution, p16 positivity (55% vs. 43%, P = .12), neck dissection rates (77% vs. 65%, P = .51), and administration of chemotherapy (55% vs. 65%, P = .55). Median follow-up for PSRT and PRT groups were 24 and 28 months, respectively (P = .04). Two-year RFS was 86% and 74% for PSRT and PRT patients, respectively (log-rank P = .30). Three and six patients recurred after PSRT and PRT, respectively. Two-year OS for PSRT and PRT patients was 91% and 74%, respectively (log-rank P = .31). Compared to PRT, PSRT was associated with statistically significantly less: grade 2+ mucositis (18% vs. 91%, P < .01), new opioid requirement (27% vs. 91%, P < .01), mean weight loss during RT (6.2 lbs vs. 17.4 lbs, P < .01), feeding tube placement during RT (5% vs. 43%, P < .01), and treatment-related unplanned hospitalizations (9% vs. 39%, P = .04).

CONCLUSION

Following TORS-assisted management of patients with pT0 HNCUP, we observed reduced toxicity following PSRT compared to PRT without apparent compromise of disease cure.

LEVEL OF EVIDENCE

Level 3 evidence, retrospective review comparing cases and controls Laryngoscope, 130:691-697, 2020.

PET/CT Evaluation of Head and Neck Cancer of Unknown Primary

The diagnosis of carcinoma of unknown primary in the head and neck is made when there is a metastasis but no primary lesion is identified after physical exam and diagnostic CT or MR imaging. PET/CT is the first step in searching for a primary lesion, followed by more invasive techniques such as endoscopy and surgery. Knowledge of the different tumor histologic types, preferential locations of nodal spread, imaging pitfalls, and other special considerations such as cystic metastases can be helpful in the ultimate identification of primary tumors, which leads to improved overall patient survival.

Association of Mycoplasma Hominis and head and neck cancer with unknown primary

INTRODUCTION

Beside HPV infection, there is currently no evidence of association between head and neck squamous cell carcinomas and microbial infections. We report the case of a cervical squamous cell carcinoma by Mycoplasma hominis.

CASE SUMMARY

A 20-year-old woman, consulted for a swelling on the left cervical side. Clinical examination found a large fixed mass. Biological tests found no evidence of infection. Biopsies of the cervical lesion diagnosed an HPV negative squamous cell carcinoma. Microbiological tests of 16sRNA identification showed the presence of Mycoplasma hominis in the 3 specimens. The patient was treated by induction chemotherapy associated to antibiotherapy, followed by chemo-radiotherapy.

DISCUSSION

The present case suggests that oropharyngeal infection by Mycoplasma hominis might be more frequent than expected, that 16sRNA is an efficient technique to isolate this pathogen and finally that further studies are required to document its potential oncogenic role in head and neck squamous cell carcinomas.

Relationship of human papillomavirus with diseases of the oral cavity

Over the last few decades, the human papillomavirus (HPV) infection has emerged as a new epidemic and become a health issue due to its involvement in several cancers affecting the cervix, the anogenital region and the oropharynx. In this review, we aim to understand and explain the distinctive features of HPV-related oropharyngeal squamous cell carcinoma based on its epidemiological data, risk factors, specific topography, HPV subtypes most frequently involved, HPV-status diagnosis, clinical behaviour, prognosis, treatment, and preventive measures. In addition, the relationship of HPV with the development of other head and neck carcinomas and benign lesions of the oral cavity will also be discussed.

The Impact of a Stepwise Approach to Primary Tumor Detection in Squamous Cell Carcinoma of the Neck With Unknown Primary

OBJECTIVES/HYPOTHESIS

To examine the cumulative effect of diagnostic steps for primary tumor identification in patients with head and neck squamous cell carcinoma of unknown primary (HNSCCUP), including lingual tonsillectomy, and the impact of primary tumor identification on subsequent treatment.

STUDY DESIGN

Retrospective analysis.

METHODS

We reviewed the records of 110 patients diagnosed with HNSCCUP between 2003 and 2015. Results of diagnostic imaging (fluorodeoxyglucose-positron emission tomography/computed tomography [FDG-PET/CT]), tumor detection with direct laryngoscopy with biopsies, palatine tonsillectomy, and transoral robotic surgery (TORS) lingual tonsillectomy were recorded. Associations between demographic and treatment variables with overall survival (OS) and progression-free survival (PFS) were modeled with Cox proportional hazards models.

RESULTS

FDG-PET/CT was suspicious for a primary site in 23/77 (30%) patients. Direct laryngoscopy identified a primary tumor in 34/110 patients (31%). Forty-seven patients underwent palatine tonsillectomy, which identified 17 primaries (36%), yielding a cumulative primary tumor identification of 51/110 (46%). Fourteen patients underwent TORS lingual tonsillectomy, which identified eight primaries (57%), resulting in a cumulative identification of 59/110 (53%). The detection rate increased from 28/63 (44%) to 31/47 (66%) after the addition of TORS lingual tonsillectomy to our institutional approach. Detection rates varied by HPV status. Primary tumor identification altered subsequent radiation planning, as patients with an identified primary tumor received radiation to a smaller volume of tissue than did those without an identified primary tumor. However, there was no significant association between primary tumor identification and OS or PFS.

CONCLUSIONS

A stepwise approach to primary tumor identification identifies a primary tumor in a majority of patients.

LEVEL OF EVIDENCE

4 Laryngoscope, 129:1610-1616, 2019.

Head and Neck Cytopathology: Human Papillomavirus-Positive Carcinomas, Including Diagnostic Updates, Testing Modalities, and Recommendations

Oropharyngeal squamous cell carcinoma caused by transcriptionally active human papillomavirus (HPV) is now well established as a unique form of head and neck cancer. Given the high frequency of metastasis to cervical lymph nodes by HPV-positive oropharyngeal squamous cell carcinomas, fine-needle aspiration (FNA) represents a widely accepted method for the sampling and diagnosis of these cancers. The recently published College of American Pathologists Guideline (2017) provides recommendations for the effective performance and interpretation of high-risk (HR) HPV testing in head and neck squamous cell carcinoma (HNSCC), including testing on FNA samples of metastatic HNSCC to cervical lymph nodes. There is a wide range of options available for HR-HPV testing in cytologic specimens.

Evaluation of Carcinoma of Unknown Primary on Cytologic Specimens

Carcinoma of unknown primary is defined as metastatic carcinoma without a clinically obvious primary tumor. Determining the tissue of origin in carcinoma of unknown primary is important for site-directed therapy. Immunohistochemistry is the most widely used tool for the work-up of metastases, but molecular profiling assays are also available. This review provides an overview of immunohistochemical stains in the work-up of metastatic carcinoma, with a focus on newer site-specific markers, and discusses the role of gene expression profiling assays for determining tissue of origin. The utility of cytopathology specimens in the evaluation of carcinoma of unknown primary also is highlighted.

Expanding primary cells from mucoepidermoid and other salivary gland neoplasms for genetic and chemosensitivity testing

Restricted availability of cell and animal models is a rate-limiting step for investigation of salivary gland neoplasm pathophysiology and therapeutic response. Conditionally reprogrammed cell (CRC) technology enables establishment of primary epithelial cell cultures from patient material. This study tested a translational workflow for acquisition, expansion and testing of CRC-derived primary cultures of salivary gland neoplasms from patients presenting to an academic surgical practice. Results showed that cultured cells were sufficient for epithelial cell-specific transcriptome characterization to detect candidate therapeutic pathways and fusion genes, and for screening for cancer risk-associated single nucleotide polymorphisms (SNPs) and driver gene mutations through exome sequencing. Focused study of primary cultures of a low-grade mucoepidermoid carcinoma demonstrated amphiregulin-mechanistic target of rapamycin-protein kinase B (AKT; AKT1) pathway activation, identified through bioinformatics and subsequently confirmed as present in primary tissue and preserved through different secondary 2D and 3D culture media and xenografts. Candidate therapeutic testing showed that the allosteric AKT inhibitor MK2206 reproducibly inhibited cell survival across different culture formats. By contrast, the cells appeared resistant to the adenosine triphosphate competitive AKT inhibitor GSK690693. Procedures employed here illustrate an approach for reproducibly obtaining material for pathophysiological studies of salivary gland neoplasms, and other less common epithelial cancer types, that can be executed without compromising pathological examination of patient specimens. The approach permits combined genetic and cell-based physiological and therapeutic investigations in addition to more traditional pathologic studies, and can be used to build sustainable bio-banks for future inquiries.This article has an associated First Person interview with the first author of the paper.

Parotid gland: an unusual site of breast cancer metastasis

Parotid gland metastases from breast cancer are an extremely rare and unusual event with a limited number of cases recorded in the literature. A 71-year-old woman with a history of ductal adenocarcinoma of the left breast presented to the maxillofacial clinic with an asymptomatic swelling of the left parotid gland. The presentation occurred 21 years after she underwent treatment for recurrent breast cancer. Investigations led to the diagnosis of a breast cancer metastasis which was oestrogen receptor and progesterone receptor positive and negative. Positron emission tomography scan confirmed this as a solitary metastasis. She was treated with aromatase inhibitors and a stable clinical response was observed on follow-up. Surgical intervention was avoided with its potential complications such as facial nerve injury. Metastasis from breast cancer to the parotid gland is a very rare phenomenon. However, in a patient with previous breast cancer, it should be considered as a possible differential diagnosis.

Diagnosis and management of metastatic neoplasms with unknown primary

In cancer of unknown primary (CUP), metastases are clinically and histologically confirmed, but the primary tumor site remains elusive after extensive work-up. CUPs make up for 2-3% of all epithelial malignancies. The two prevailing histologies are adenocarcinomas and undifferentiated carcinomas, whereas squamous cell carcinomas, neuroendocrine carcinomas and rare histologies account for the remaining 10%. The diagnostic work-up in CUP relies strongly on a detailed immunohistological (IHC) analysis in order to characterize the tumor type, nowadays aided by molecular techniques. Diagnostics also include a thorough clinical examination, a basic lab draw with the most relevant tumor markers, and cross sectional imaging. Additional PET-CT is recommended in cervical lymph nodes suggestive of head and neck cancer and in limited metastases potentially treatable in curative intent. As for treatment, it is paramount to identify patients who fall into one of the six well defined "favorable" subset categories, namely extragonadal germ cell tumors, adenocarcinoma with isolated unilateral axillary lymph nodes in female patients, squamous cell carcinoma with neck lymph nodes, squamous cell carcinoma with inguinal lymph nodes, serous papillary peritoneal carcinomatosis in females and blastic bone metastasis in males with elevated PSA. These subsets are distinct both regarding the required treatment and the comparably favorable prognosis. Within the remaining "unfavorable" group, patients of colon and renal cancer type should be identified based on IHC and clinical picture, since the prognosis of these patients seems to improve with the use of therapy tailored to the presumed primary as well. For the few patients with limited metastases it should be assessed whether they are candidates for surgery, radiotherapy or surgery followed by irradiation in curative intent. The remaining majority of patients are treated with empiric palliative chemotherapy, typically a platinum - paclitaxel combination, though the level of evidence for this therapy recommendation is low. Gemcitabine alone or in combination can be used as an alternative. Decoding of the molecular profiles in CUP offers the prospect of targeted therapy with novel agents. However, there appears to be no uniform molecular pattern for CUP, and the observed molecular diversity thus poses a challenge to respective clinical trials.

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.

Developing a new diagnostic algorithm for human papilloma virus associated oropharyngeal carcinoma: an investigation of HPV DNA assays

Background

Human papilloma virus (HPV) has been implicated in the development of a large proportion of oropharyngeal squamous cell carcinoma (OPSCC). Current techniques used to diagnose HPV etiology require histopathologic analysis. We aim to investigate the diagnostic accuracy of a new application non-histopathologic diagnostic tests to help assist diagnosis of HPV-related oropharyngeal tumors.

Methods

Patients with OPSCC with nodal metastasis were consecutively recruited from a multidisciplinary cancer clinic. Appropriate samples were collected and analyzed. The various tests examined included COBAS® 4800, Cervista® HR and Genotyping. These tests were compared to p16 staining, which was used as the diagnostic standard. StataIC 14.2 was used to perform analysis, including sensitivity, specificity and receiver operator characteristic [ROC] curves.

Results

The COBAS® FNA (area under ROC 0.863) and saliva (area under ROC 0.847) samples performed well in diagnosing HPV positive and negative tumors. Samples tested with Cervista® did not corroborate p16 status reliably. We were able to increase the diagnostic yield of the COBAS® FNA samples by applying the results of the saliva test to negative FNA samples which correctly identified 11 additional p16 positive tumors (area under ROC 0.915).

Conclusion

Surrogate testing for HPV using alternate methods is feasible and closely predicts the results of standard diagnostic methods. In the future, these could minimize invasive procedures for diagnosing HPV-related oropharyngeal cancer, but also help to diagnose and treat patients with unknown primaries.

Morphologic diversity in human papillomavirus-related oropharyngeal squamous cell carcinoma: Catch Me If You Can!

As the human papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma epidemic has developed in the past several decades, it has become clear that these tumors have a wide variety of morphologic tumor types and features. For the practicing pathologist, it is critical to have a working knowledge about these in order to make the correct diagnosis, not to confuse them with other lesions, and to counsel clinicians and patients on their significance (or lack of significance) for treatment and outcomes. In particular, there are a number of pitfalls and peculiarities regarding HPV-related tumors and their nodal metastases that can easily result in misclassification and confusion. This article will discuss the various morphologic types and features of HPV-related oropharyngeal carcinomas, specific differential diagnoses when challenging, and, if established, the clinical significance of each finding.

Cutaneous Squamous Cell Carcinoma: A Review of High-Risk and Metastatic Disease

Non-melanoma skin cancer represents one-third of all malignancies and its incidence is expected to rise until the year 2040. Cutaneous squamous cell carcinoma (cSCC) represents 20 % of all non-melanoma skin cancer and is a deadly threat owing to its ability to metastasize to any organ in the body. Therefore, a better understanding of cSCC is essential to strengthen preventative measures and curable treatment options. Currently, research demonstrates that cSCC is diagnosed at a rate of 15-35 per 100,000 people and is expected to increase 2-4 % per year. With respect to metastatic cSCC, this disease is more common in men; people over the age of 75 years; and inhabitants of the south and mid-west USA. In 2010, the American Joint Committee on Cancer updated the Cancer Staging Manual's primary tumor designation to now include high-risk factors; however, factors such as immunosuppression and tumor recurrence were not included. Other staging systems such as Brigham and Women's Hospital have allowed for increased stratification of cSCC. High-risk cSCC is defined as a cSCC that is staged as N0, extends beyond basement membrane, and has high-risk features associated with sub-clinical metastasis. High-risk features are depth of invasion (>2 mm), poor histological differentiation, high-risk anatomic location (face, ear, pre/post auricular, genitalia, hands, and feet), perineural involvement, recurrence, multiple cSCC tumors, and immunosuppression. Epidermal growth factor receptor and nuclear active IκB kinase (IKK) expression are also predictive of metastatic capabilities. Clinically, the initial lesions of a cSCC tumor can present as a painless plaque-like or verrucous tumor that can ultimately progress to being large, necrotic, and infected. Tumors can also present with paresthesias or lymphadenopathy depending on the location involved. With respect to prognosis, metastatic cSCC is lethal, with several large studies demonstrating a mortality rate of >70 %. Therefore, treatment of metastatic cSCC is difficult and depends on the location involved and extent of metastasis. Treatment options include surgery, radiation therapy, chemotherapy, and any combination of the above. Surgery alone can be used for metastatic cSCC treatment, but is not as effective as surgery in conjunction with radiation therapy. Radiation therapy has some success as a monotherapy in low-risk or cosmetically sensitive areas such as the external ear, eyelid or nose. According to the 2013 National Comprehensive Cancer Network Guidelines, cisplatin as a single agent or combined with 5-fluorouracil hold the strongest support for the treatment of metastatic cSCC; however, the supporting evidence is inconsistent and a curative chemotherapeutic approach is still lacking. Epidermal growth factor receptor inhibitors are a newer class of agents being used in metastatic cSCC and hold some promise as a therapy for this disease. Other areas of interest in finding curative treatments for metastatic cSCC include p53, hypermethylation of specific genes, chromatin remodeling genes, and the RAS/RTK/PI3K pathway. This review addresses the epidemiology, staging, risk factors, clinical presentation, management, and new trends in the treatment of high-risk and metastatic cSCC.

Challenges in establishing the diagnosis of human papillomavirus-related oropharyngeal carcinoma

OBJECTIVES/HYPOTHESIS

To describe initial presentations and idiosyncrasies in establishing the diagnosis for human papillomavirus-related (HPV(+) ) compared to HPV-unrelated (HPV(-) ) oropharyngeal carcinoma (OPC).

STUDY DESIGN

A single institution retrospective series derived from an institutional prospectively compiled database supplemented by chart review.

METHODS

We reviewed consecutive OPC patients referred to an academic tertiary cancer center from 2009 to 2011. HPV status was evaluated by p16 staining. Signs/symptoms and procedures to establish diagnosis were recorded independently by two abstractors blinded to the HPV status during data retrieval. Initial presentations (signs/symptoms), interval, and the procedures to establish the diagnosis were compared between HPV(+) and HPV(-) OPC.

RESULTS

The most common initial presentation was an asymptomatic nodal mass for HPV(+) patients (n = 208; 69% vs. 29%, P < .001) in contrast to dysphagia/odynophagia for HPV(-) (n = 96; 34% vs. 63%, P < .001). Protracted interval (>12 months) from onset of signs/symptoms to diagnosis was observed in 18 (9%) HPV(+) versus three (3%) HPV(-) patients (P = .058). More HPV(+) patients required repeated (≥2) biopsy procedures (56% vs. 10%, P < .001). Misattribution to other disease occurred in eight (4%) HPV(+) patients (seven were mistaken as having a "branchial cleft cyst" when there were cystic lymph nodes and one as having a "lymphoma") compared to none in HPV(-) .

CONCLUSIONS

About two-thirds of HPV(+) patients present with an asymptomatic neck mass and often require multiple biopsy procedures to establish the diagnosis. Idiosyncrasies in appreciating the diagnostic setting (cystic lymph node, misattribution to other entities, or submucosal location of the tumor) or patient-related factors could delay the diagnosis of HPV(+) OPC.

LEVEL OF EVIDENCE

4 Laryngoscope, 126:2270-2275, 2016.