Neck dissection for unknown cancer of the head and neck in the era of chemoradiation

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.

Evaluation of risk-tailored individualized selection of radiation therapy target volume for Head and Neck Carcinoma of Unknown Primary

PURPOSE

Intensity-modulated radiation therapy (IMRT) has enabled risk-tailored approach to elective mucosal and nodal clinical target volumes (CTVs) in treatment of head and neck carcinoma of unknown primary (HNCUP). This study report outcomes following such approach.

METHODS

HNCUP patients treated with definitive IMRT between 2005 and 2018 were reviewed. Local failure (LF), regional failure (RF), distant metastasis (DM), overall survival (OS) and grade ≥3 late toxicity (LT) were analyzed. Multivariable analysis (MVA) was used to identify OS predictors for entire cohort and cN2-3 subgroup.

RESULTS

A total of 203 patients were eligible: cN1 (7%), cN2a (14%), cN2b (46%), cN2c (14%) and cN3 (19%). Among 118 patients with known HPV status (by p16 staining), 81 (68%) were positive. IMRT target volume spared contralateral tonsil (55%), bilateral or contralateral sides of hypopharynx (72%), nasopharynx (72%), larynx (87%) and contralateral uninvolved neck (21%). Median follow-up was 5 years. Five-year LF, RF, DM, OS, and LT were 3%, 14%, 10%, 79%, and 7% respectively. Four patients developed mucosal recurrence: 3 within and 1 at the margin of the elective mucosal CTV. None of ipsilateral neck irradiation patients failed in the contralateral uninvolved neck. MVA identified cN2c-N3, HPV-negative status and older age as predictors for inferior OS. Within cN2-3 subgroup (n=189): cN2c-N3, HPV-negative status and older age predicted lower OS, while concurrent chemotherapy was associated with better OS.

CONCLUSION

Definitive IMRT with risk-adaptive radiation volume de-escalation for HNCUP resulted in high probability of tumor control with acceptable rate of late toxicity.

Factors Influencing the Outcome of Head and Neck Cancer of Unknown Primary (HNCUP)

Background: This study on patients with head and neck cancer of unknown primary (HNCUP) assesses the impact of surgical and non-surgical treatment modalities and the tumour biology on the oncological outcome. Methods: A total of 80 patients with HNCUP (UICC I−IV) were treated with simultaneous neck dissection followed by adjuvant therapy, between 1 January 2007 and 31 March 2020. As the primary objective, the influence of treatment modalities on the overall survival (OS), the disease-specific survival (DSS) and the progression-free survival (PFS) were analysed in terms of cox regression and recursive partitioning. The tumour biology served as secondary objectives. Results: The 5-year OS for the entire cohort was 67.7%, (95% CI: 54.2−81.2%), the 5-year DSS was 82.3% (72.1−92.5%) and the 5-year PFS was 72.8% (61.8−83.8%). Cox regression revealed that patients undergoing adjuvant radiotherapy only had a four times higher risk to die compared to patients receiving chemoradiation therapy (HR = 4.45 (1.40; 14.17), p = 0.012). The development of distant metastases had a significantly negative impact on OS (HR = 8.24 (3.21−21.15), p < 0.001) and DSS (HR = 23.79 (6.32−89.56), p < 0.001). Recursive portioning underlined the negative influence of distant metastases on OS (3.2-fold increase in death probability) and DSS (4.3-fold increase in death probability), while an UICC stage of IVb increased the risk for further progression of the disease by a factor of 2. Conclusions: The presence of distant metastases as well as adjuvant treatment with radiation without concomitant chemotherapy, were among others, significant predictors for the overall survival of HNCUP patients, with distant metastases being the most significant predictor.

Sparing the Larynx and Hypopharynx With Radiation Therapy for Squamous Cell Carcinoma of Unknown Primary Site and Predominant Adenopathy in Level IIA

PURPOSE

There is controversy about the need to target the mucosa of the larynx and hypopharynx during radiation therapy (RT) for squamous cell carcinoma of an unknown primary site (SCCA-UP). By 1997, the policy in our department was to target only the oropharynx and nasopharynx in patients with SCCA-UP metastatic to the level II cervical nodes. The purpose of this study was to report the rate of cancer recurrence in the larynx or hypopharynx using an approach that excluded these areas from the RT target volumes.

METHODS AND MATERIALS

The inclusion criteria for this study were RT in our department for SCCA-UP between January 1, 1997, and December 31, 2019; no history of surgery that could disrupt the cervical lymphatics; predominant adenopathy in level IIA; and neck stage N1-2c. We excluded N3 because the incidental dose to the larynx and hypopharynx is usually high in patients with a >6-cm nodal conglomerate.

RESULTS

The study population was comprised of 50 patients with a median follow-up after RT of 7.1 years. No patient developed recurrent cancer in a mucosal site (0/50), 2% (1/50) developed a neck recurrence in a high-dose area with synchronous distant metastases, and 2% (1/50) developed distant metastases with no evidence of local or regional recurrence.

CONCLUSIONS

When delivering RT for SCCA-UP metastatic predominantly to level IIA, it is not necessary to target the mucosa of the larynx or hypopharynx. The extent to which the incidental RT dose to these areas contributes to cancer control is not evaluated in this study.

A population-based analysis of clinical features and lymph node dissection in head and neck malignant neurogenic tumors

Background

The influence of lymph node dissection (LND) on survival in patients with head and neck neurogenic tumors remains unclear. We aimed to determine the effect of LND on the outcomes of patients with head and neck neurogenic tumors.

Methods

Data of patients with surgically treated head and neck neurogenic tumors were identified from the Surveillance, Epidemiology, and End Results (SEER) database (1975–2016) to investigate the relationship between LND and clinical outcomes by survival analysis. Subgroup analysis was performed in IVa and IVb group.

Results

In total, 662 head and neck neurogenic tumor patients (median age: 49.0 [0–91.0] years) met the inclusion criteria, of whom 13.1% were in the IVa group and 86.9% were in the IVb group. The median follow-up time was 76.0 months (range: 6.0–336.0 months), and the 5-year and 10-year overall survival was 82.4% (95% CI, 0.79–0.85) and 69.0% (95% CI, 0.64–0.73). Cox regression analysis revealed older age (P < .001), advanced stage (P = .037), African American race (P = .002), diagnosis before 2004 (P < .001), and chemotherapy administration (P < .001) to be independent negative predictors of overall survival. Kaplan-Meier analysis demonstrated that LND was not a predictor of clinical nodal negativity (cN0) in either IVa or IVb patients.

Conclusions

In head and neck neurogenic patients, LND may not impact the outcome of cN0 in either IVa or IVb group. These data can be recommended in guiding surgical plan and future studies.

Impact of Neck Dissection in Head and Neck Squamous Cell Carcinomas of Unknown Primary

Simple Summary

A retrospective multicentric study of 322 patients with head and neck cancers of unknown primary (HNCUP) was performed testing the impact of neck dissection (ND) extent on nodal relapse, progression-free survival and survival. After 5 years, the incidence of nodal relapse was 13.4%, and progression-free survival (PFS) was 59.1%. In multivariate analysis after adjusting for nodal stage, the risk of nodal relapse or progression was reduced with lymphadenectomy, selective ND or radical/modified ND but survival rates were similar. Patients undergoing lymphadenectomy or ND had significantly better PFS and a lower nodal relapse incidence in the N1 + N2a group, but the improvement was not significant for the N2b or N2 + N3c patients. Severe toxicity rates exceeded 40% with radical ND. In HNCUP, ND improves PFS regardless of nodal stage but fails to improve survival. The magnitude of the benefit of ND did not appear to depend on ND extent and decreased with a more advanced nodal stage.

Abstract

Purpose: Management of head and neck cancers of unknown primary (HNCUP) combines neck dissection (ND) and radiotherapy, with or without chemotherapy. The prognostic value of ND has hardly been studied in HNCUP. Methods: A retrospective multicentric study assessed the impact of ND extent (adenectomy, selective ND, radical/radical-modified ND) on nodal relapse, progression-free survival (PFS) or survival, taking into account nodal stage. Results: 53 patients (16.5%) had no ND, 33 (10.2%) had lymphadenectomy, 116 (36.0%) underwent selective ND and 120 underwent radical/radical-modified ND (37.3%), 15 of which received radical ND (4.7%). With a 34-month median follow-up, the 3-year incidence of nodal relapse was 12.5% and progression-free survival (PFS) 69.1%. In multivariate analysis after adjusting for nodal stage, the risk of nodal relapse or progression was reduced with lymphadenectomy, selective or radical/modified ND, but survival rates were similar. Patients undergoing lymphadenectomy or ND had a better PFS and lowered nodal relapse incidence in the N1 + N2a group, but the improvement was not significant for the N2b or N2 + N3c patients. Severe toxicity rates exceeded 40% with radical ND. Conclusion: In HNCUP, ND improves PFS, regardless of nodal stage. The magnitude of the benefit of ND does not appear to depend on ND extent and decreases with a more advanced nodal stage.

Influence of postoperative radiotherapy target volumes in unilateral head and neck carcinoma of unknown primary: A multicentric study using propensity score

OBJECTIVE

To compare the impact of two radiation modalities on loco-regional control, survival and tumour emergence, after node dissection for an unilateral head and neck carcinoma of unknown primary (HNCUP).

MATERIALS AND METHODS

This is a multicentric retrospective study of 138 patients with unilateral HNCUP treated between 2002 and 2017. The absence of primary tumour was assessed by a systematic panendoscopy and positron emission tomography. Neck dissection was initially performed for all patients. Radiation Therapy was delivered on ipsilateral lymph node areas in 62 cases (44%: UL-RT group) and on bilateral lymph node areas and the entire pharyngeal mucosa in 77 cases (56%: COMP-RT group). Impact of radiation modalities on locoregional control and overall survival was assessed using propensity score matching method in order to balance baseline characteristics between the two groups.

RESULTS

The population included 80.4% men, 80.4% smokers, 32.6% P16 positive tumours and 71.0% extracapsular extension. After a median follow-up of 5 years, the locoregional control rate was 80.3% in the UL-RT group and 75.3% in the COMP-RT group (p = 0.688). The corresponding rate of contralateral lymph node recurrence was 0% versus 2.6% (p = 0.503) and the rate of tumour emergence was 11.5% versus 9.1% (p = 0.778). No significant difference was observed between the UL-RT and the COMP-RT groups for overall survival (p = 0.9516), specific survival (p = 0.4837) or tumour emergence (p = 0.9034).

CONCLUSION

UL-RT seems to provide similar outcomes as COMP-RT in unilateral HNCUP post-operative management.

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.

Long-term results of elective mucosal irradiation for head and neck cancer of unknown primary in Chinese population: The EMICUP study

Objective

Controversy still exists regarding the volume of radiation for head and neck cancer of unknown primary (HNCUP). Theoretically, elective mucosal irradiation (EMI) should achieve a balance between survival and toxicity. This prospective study was conducted to evaluate the long‐term benefit of EMI in Chinese HNCUP patients.

Methods

A phase II, single‐arm trial was performed at two centers in China. HNCUP patients with pathologically confirmed metastatic squamous cell carcinoma or poorly differentiated carcinoma were enrolled. Patients with metastatic lymph nodes limited to level IV and/or the supraclavicular fossa were excluded. The EMI approach was specifically customized to Chinese patients by differentiating HNCUP as putative nasopharyngeal carcinoma (NPC) or non‐putative NPC. The primary endpoint was 3‐year mucosal recurrence‐free survival (MRFS).

Results

A total of 48 patients were enrolled between 02/02/2010 and 08/01/2018; 46 patients were analyzed, including 24 putative NPC and 22 non‐putative NPC patients. No primary recurrence was observed during a median follow‐up period of 70 months, and only 1 patient experienced out of field recurrence in the contralateral neck. The 3‐year MRFS was 90.6% (95%CI: 76.4%‐96.4%). The 5‐year MRFS, regional‐recurrence free survival (RRFS) and overall survival (OS) were 90.6% (95%CI: 76.4%‐96.4%), 86.0% (95%CI: 71.1%‐93.7%), and 90.6% (95%CI: 76.4%‐96.4%), respectively. No grade 4 acute or late toxicities occurred, and the most frequent grade 3 acute toxicity was oral mucositis (45.7%).

Conclusion

To the best of our knowledge, this is the first prospective study to evaluate the long‐term outcomes of EMI in Chinese HNCUP patients. Excellent MRFS and OS rates were observed. Further randomized studies are warranted.

Unilateral or bilateral irradiation in cervical lymph node metastases of unknown primary? A retrospective cohort study

INTRODUCTION

Patients with cervical lymphadenopathy of unknown primary carcinoma (CUP) usually undergo neck dissection and irradiation. There is an ongoing controversy regarding the extent of nodal and mucosal volumes to be irradiated. We assessed outcomes after bilateral or unilateral nodal irradiation.

METHODS

This retrospective multicentre study included patients with CUP and squamous cellular carcinoma who underwent radiotherapy (RT) between 2000 and 2015.

RESULTS

Of 350 patients, 74.5% had unilateral disease and 25.5% had bilateral disease. Of 297 patients with available data on disease and irradiation sides, 61 (20.5%) patients had unilateral disease and unilateral irradiation, 155 (52.2%), unilateral disease and bilateral irradiation and 81 (27.3%), bilateral disease and bilateral irradiation. Thirty-four (9.7%) and 217 (62.0%) patients received neoadjuvant and/or concomitant chemotherapy, respectively. Median follow-up was 37 months. Three-year local, regional, locoregional failure rates and CUP-specific survival were 5.6%, 11.7%, 15.0% and 84.7%, respectively. In patients with unilateral disease, the 3-year cumulative incidence of regional/local relapse was 7.7%/4.3% after bilateral irradiation versus 16.9%/11.1% after unilateral irradiation (hazard ratio = 0.56/0.61, p = 0.17/0.32). The cumulative incidence of CUP-specific deaths was 9.2% after bilateral irradiation and 15.5% after unilateral irradiation (p = 0.92). In multivariate analysis, mucosal irradiation was associated with better local control, whereas no neck dissection, ≥N2b and interruption of RT for more than 4 days were associated with poorer regional control. Toxicity was higher after bilateral irradiation (p < 0.05). No positron-emission tomography-computed tomography, largest node diameter, ≥N2b, neoadjuvant chemotherapy and interruption of RT were associated with poorer cause-specific survival.

CONCLUSION

Bilateral nodal irradiation yielded non-significant better nodal and mucosal control rates but was associated with higher rates of severe toxicity.