Transoral robotic surgery for tonsillar cancer: Addressing the contralateral tonsil

Transoral Robotic Surgery for Oropharyngeal Squamous Cell Carcinoma of the Tonsil versus Base of Tongue: A Systematic Review and Meta-Analysis

Simple Summary

Transoral Robotic Surgery (TORS) has become widely adopted for the surgical removal of oropharyngeal squamous cell carcinoma (OPSCC). However, it is currently unknown if TORS has equal efficacy and outcomes in patients with tonsillar or base of tongue (BOT) OPSCC. Therefore, we performed a systematic review, including articles describing the surgical management of OPSCC with TORS that compared margin status, complications, and recurrence between tonsil and BOT. BOT OPSCC had a higher rate of positive margins compared to tonsillar OPSCC. However, no differences were seen in the recurrence or postoperative hemorrhage rates of BOT and tonsillar OPSCC. While a higher rate of positive margins was seen in BOT OPSCC when compared to tonsillar OPSCC, this did not translate to a higher recurrence rate in the BOT group. Future research on which subset of patients with BOT is more likely to have positive margins is warranted to improve the utility of TORS further.

Abstract

Transoral Robotic Surgery (TORS) has become widely adopted for the surgical removal of oropharyngeal squamous cell carcinoma (OPSCC), with the most common locations being in the tonsil and base of tongue (BOT). However, it is currently unknown if TORS has equal efficacy and outcomes in patients with tonsillar or BOT OPSCC. Therefore, the aim of this study was to compare the margin status and recurrence rates of tonsillar and BOT OPSCC after TORS. Per PRISMA guidelines, PubMed, Scopus, and CINAHL were systematically searched from inception to 2/28/2022. Articles including the surgical management of OPSCC with TORS that compared margin status, complications, and recurrence between tonsil and BOT were included. Meta-analyses of proportions and odds ratios were performed. A total of 28 studies were included, comprising 1769 patients with tonsillar OPSCC and 1139 patients with BOT OPSCC. HPV positivity was seen in 92.3% of tumors. BOT OPSCC had a higher rate of positive margins compared to tonsillar OPSCC (28.1% [95%CI 15.1–43.3] vs. 7.5% [95%CI 3.3–13.3]). No differences were seen in recurrence between BOT and tonsillar OPSCC (OR 1.1 [95%CI 0.8–1.5], p = 0.480). In addition, no differences in postoperative hemorrhage were seen between tonsillar and BOT OPSCC (10.7% [95%CI 6.1–16.5] vs. 8.8% [95% CI 1.5–21.3]). While a higher rate of positive margins was seen in BOT OPSCC when compared to tonsil OPSCC, this did not translate to a higher recurrence rate in the BOT group. Future research on which subset of patients with BOT is more likely to have positive margins is warranted to improve the utility of TORS further.

Synchronous tonsillar tumors with differing histopathology: A case report and review of the literature

Background

Tonsillar squamous cell carcinoma (TSCC) due to human papillomavirus (HPV) infection has seen a dramatic increase in recent years. Bilateral tonsillar squamous cell carcinoma (biTSCC) has a much lower incidence than unilateral TSCC and three main hypotheses of biTSCC pathogenesis prevail: field carcinogenesis, single‐clone, and multiple HPV infections.

Case

A 49‐year‐old Male with a remote history of chewing tobacco presented with symptoms of spitting up tissue and occasional hemoptysis. Physical exam showed a sole left tonsillar mass which was confirmed to be TSCC on biopsy. The patient's computed tomographic (CT) scan was consistent with this finding; however, positron emission tomography (PET) scan indicated a second tumor in the contralateral right tonsil. Surgical resection of both masses and selective neck dissection was performed, and the specimens were sent for further pathological analysis. No complications of surgery were noted and the final diagnosis of synchronous biTSCC was made. The tumors were a T2N0M0 left poorly differentiated TSCC (p16+, EGFR+, bcl2+) with basaloid features, and a T1N0M0 right well to moderately differentiated TSCC (p16+, EGFR+, bcl2−).

Conclusion

Our present case was notable for differing tumor pathology and karyotype analysis between the right and left masses, directly supporting the multiple HPV infections hypothesis of biTSCC pathogenesis. Further genetic characterization of tonsillar tumors is needed to better characterize TSCC and best guide medical/surgical therapy.

Development of second primary malignancies after transoral surgery in human papilloma virus-positive oropharyngeal squamous cell carcinoma

BACKGROUND

Little data exists regarding the incidence of oropharyngeal and upper aerodigestive tract (UADT) second primary malignancies (SPM) among human papilloma virus (HPV)-positive oropharyngeal squamous cell carcinoma (OPSCC). Here we evaluate SPM rates among patients with HPV-related OPSCC.

METHODS

A retrospective cohort study of 412 patients with HPV-related OPSCC who underwent transoral resection +/- adjuvant therapy at a single center between 1996 and 2018.

RESULTS

Twenty patients (4.9%) developed SPM of the UADT, nine (2.2%) occurring in the oropharynx. Median time to diagnosis was 59.5 months (0-173 months). Risk of SPM was lower for patients receiving adjuvant radiation (aHR: 0.25, 95%CI: 0.08-0.78). There was no difference in overall or disease-free survival between those with and without SPM.

CONCLUSION

The rate of SPM among patients with HPV-positive OPSCC is lower than reported rates among HPV-negative OPSCC. To date, this is the largest study evaluating SPM in patients with surgically treated HPV-positive OPSCC.

Incidence of synchronous contralateral tonsillar malignancy in a known case of unilateral tonsillar carcinoma

OBJECTIVE

The literature is divided with regards to contralateral tonsillectomy in a known/suspected case of ipsilateral tonsillar malignancy. In this study, we evaluate the incidence of indolent synchronous contralateral tonsillar malignancy (SCTC) in patients with known ipsilateral tonsillar malignancy.

METHODS

All patients diagnosed with ipsilateral tonsillar carcinoma (TC) at a tertiary teaching center between January 2016 and December 2019 were screened. None of the patients were suspected to have bilateral TC. All patients underwent appropriate imaging in the form of Magnetic resonance imaging and computed tomography of head and neck region and then underwent bilateral tonsillectomy. The prevalence of bilateral tonsillar malignancy and the factors predicting them were analyzed.

RESULTS

In all 59 patients were included in the study. The mean and median age of the patient population was 60.8 and 59 years, respectively, with a male to female ratio of 3.2:1. The incidence of bilateral tonsillar malignancy in carcinoma of unknown primary (CUP) was 3/10 (33.3%). Among the remaining 49 patients, incidence of synchronous contralateral tonsillar carcinoma (SCTC) was 2/49 (4.08%). Overall, 5/59 (8.5%) patients had synchronous bilateral tonsillar malignancy. Furthermore, dysplasia was found in the contralateral tonsil in 4/10 (40%) CUP patients. Among the remaining 49 patients, dysplasia was seen in the contralateral tonsil in 20/49 (40.8%) patients. The absence of p16 expression predicted higher probability of SCTC. Factors like gender, T stage, nodal status or smoking did not predict SCTC.

CONCLUSION

We recommend bilateral tonsillectomy in all patients with suspected or proven TC (unilateral or bilateral) and CUP as it helps identify indolent SCTC and it does not add any significant morbidity to the patients.

LEVEL OF EVIDENCE

III.

Second Primary Tumors in Patients Presenting With Unilateral HPV-Associated Tonsillar Squamous Cell Carcinoma

OBJECTIVE

To describe and compare rates of metachronous and synchronous second primaries of the contralateral tonsil in patients with primary HPV(+) tonsillar squamous cell carcinoma (SCC).

STUDY DESIGN

Retrospective cohort study.

MATERIALS AND METHODS

This is a single tertiary care center retrospective case series, from 2006 to 2019, of HPV(+) tonsillar SCC patients who underwent primary surgical resection with unilateral wide-field tonsillectomy or bilateral tonsillectomy for diagnostic or therapeutic purposes. A metachronous second primary is one diagnosed >6 months after completion of surgical treatment. A synchronous second primary is one diagnosed during bilateral tonsillectomy for unilateral HPV(+) tonsillar SCC. Rates of second primary and patient characteristics were compared using chi-square tests.

RESULTS

About 303 patients underwent unilateral surgical resection +/- adjuvant therapy for HPV(+) tonsillar SCC. One (0.3%) developed a metachronous second primary in the contralateral tonsil 11.9 years following treatment. Fifty-seven patients with HPV(+) tonsillar SCC underwent bilateral tonsillectomy, and 37/57 (65%) had no clinical signs for contralateral disease. Of these, only 1/37 (2.7%) was incidentally found to have a synchronous second primary. Twenty patients underwent bilateral tonsillectomy due to clinical concern for contralateral disease. Of these, 3/20 (15%) were found to have a synchronous HPV(+) SCC in the contralateral tonsil.

CONCLUSIONS

The prevalence of metachronous second primary after appropriate treatment of HPV(+) tonsillar SCC is very low (0.3%) and so is the chance of incidentally discovering a synchronous second primary during bilateral tonsillectomy (2.7%). We do not recommend bilateral tonsillectomy as a part of the routine algorithm in the surgical management of these patients.

LEVEL OF EVIDENCE

3 Laryngoscope, 2021.

Revisiting the Recommendation for Contralateral Tonsillectomy in HPV-Associated Tonsillar Carcinoma

Objective

Despite epidemiologic evidence that second primaries occur infrequently in HPV (human papillomavirus)–associated oropharyngeal squamous cell carcinoma, recent recommendations advocate for elective contralateral palatine tonsillectomy. We aimed to study this discordance and define the necessary extent of up-front surgery in a large contemporary cohort with long-term follow-up treated with unilateral transoral robotic surgery. We hypothesized that second primaries are discovered exceedingly rarely during follow-up and that survival outcomes are not compromised with a unilateral surgical approach.

Study Design

Retrospective cohort analysis.

Setting

Tertiary care academic center between 2007 and 2017.

Methods

Records for patients with p16-positive oropharyngeal squamous cell carcinoma of the tonsil and workup suggestive of unilateral disease who underwent ipsilateral transoral robotic surgery were analyzed for timing and distribution of locoregional recurrence, distant metastases, and second primary occurrence as well as survival characteristics.

Results

Among 295 included patients, 21 (7.1%) had a locoregional recurrence; 17 (5.8%) had a distant recurrence; and 3 (1.0%) had a second primary during a median follow-up of 48.0 months (interquartile range, 29.5-62.0). Only 1 (0.3%) had a second primary found in the contralateral tonsil. The 2- and 5-year estimates of overall survival were 95.5% (SE, 1.2%) and 90.1% (SE, 2.2%), respectively, while the 2- and 5-year estimates of disease-free survival were 90.0% (SE, 1.8%) and 84.7% (SE, 2.3%).

Conclusion

Second primary occurrence in the contralateral tonsil was infrequent, and survival outcomes were encouraging with unilateral surgery. This provides a rationale for not routinely performing elective contralateral tonsillectomy in patients whose workup suggests unilateral disease.

Systematic Review of Second Primary Oropharyngeal Cancers in Patients With p16+ Oropharyngeal Cancer

OBJECTIVE

To systematically review the literature to determine the prevalence and clinical outcomes of second primary oropharyngeal squamous cell carcinoma (OPSCC).

DATA SOURCES

Search strategies created with a medical librarian were implemented using multiple databases in October 2019.

REVIEW METHODS

The population of interest included adults age >18 years with a p16+ or human papillomavirus-positive OPSCC. The outcome was a synchronous or metachronous second primary OPSCC. Inclusion and exclusion criteria were designed to capture all study designs. In total, 685 records were identified by the search strategy. Two reviewers independently performed the review, extracted data, and performed a quality assessment. Primary Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. A random-effects model was used for the meta-analysis.

RESULTS

A total of 2470 patients with 35 second primary OPSCCs from 15 studies were identified. The pooled prevalence of second primary OPSCC was 1.4% (range, 0%-14.3%). In the random-effects model, the prevalence was estimated at 1.3% (95% CI, 0.7%-2.3%; P = .51, I² = 52%). Of the 30 patients with treatment information, 26 (86.7%) received surgical treatment, while 4 (13.3%) underwent nonsurgical therapy. Of the 29 patients with available survival information, 22 (75.9%) had no evidence of disease at last follow-up, 5 (17.2%) ultimately died of disease, and 2 (6.9%) were alive with disease.

CONCLUSION

Overall, the rate of second primary OPSCC in patients with an index p16+ OPSCC is low, and most patients are successfully treated. Insufficient evidence currently exists to recommend routine elective tonsillectomy during surgical treatment of p16+ OPSCC.

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.

Two for the price of one: Prevalence, demographics and treatment implications of multiple HPV mediated Head and Neck Cancers

OBJECTIVES

HPV mediated head and neck squamous cell carcinoma (HPVmHNSCC) is increasing in prevalence in the United States, as are reports of patients with multiple HPVmHNSCCs. The prevalence, demographics, and treatment implications of this emerging clinical entity are poorly understood.

MATERIALS AND METHODS

We performed a multitiered assessment of patients with multiple HPVmHNSCC including: 1. systematic review of the literature, 2. query of the 2017 Surveillance, Epidemiology and End Results (SEER) database and 3. institutional level reporting at two high volume academic centers.

RESULTS

Systematic literature review: 13 articles met inclusion criteria (48 patients with multiple HPVmHNSCC). Pooled prevalence rate of multiple HPVmHNSCC was 2.64%. SEER database: 60(0.95%) patients with HPVmHNSCC had two tumors. Patients with multiple HPVmHNSCC were more likely to be younger and present with a lower T and N stage (p < 0.025 for all). The second identified tumor was more likely to be contralateral, found synchronously, of smaller size, and to occur in the tonsil (p < 0.05 for all). Institutional reporting: 17(1.69%) patients with HPVmHNSCC had two primary tumors. Similar to the SEER database, patients with multiple HPVmHNSCC were more likely to present with a low T stage and tonsil location (p < 0.007 for both).

CONCLUSION

Multiple HPVmHNSCCs occur in a subset of HPVmHNSCC cases with distinct characteristics. Thorough interrogation of all oropharyngeal subsites should be performed as part of the initial workup for HPVmHNSCC, with consideration given to contralateral tonsillectomy at the time of surgical resection for HPV mediated tonsil cancers due to the prevalence of contralateral tonsil primaries.

Transoral robotic surgery for oropharyngeal cancer: patient selection and special considerations

The increasing incidence of oropharyngeal squamous cell carcinoma (OPSCC) emphasizes the importance of optimizing treatment for the disease. Historical protocol has utilized definitive radiation and invasive open procedures; these techniques expose the patient to significant risks and morbidity. Transoral robotic surgery (TORS) has emerged as a therapeutic modality with promise. Here, the literature regarding proper patient selection and other considerations for this procedure was reviewed. Multiple patient and tumor-related factors were found to be relevant for successful use of this treatment strategy. Outcomes regarding early and advanced-stage OPSCC were analyzed. Finally, the literature regarding use of TORS in three distinct patient populations, individuals with primary OPSCC, carcinoma of unknown primary and those with recurrent OPSCC, was examined.