Patterns of failure in patients with head and neck carcinoma of unknown primary treated with radiation therapy

Is bilateral radiotherapy necessary for patients with unilateral squamous cell carcinoma of unknown primary of the head and neck region?

Background and Purpose

Squamous cell carcinoma of unknown primary (SCC-CUP) of the head and neck region remains a clinical challenge, with uncertainty surrounding the necessity of contralateral irradiation of cervical lymphatic drainage in cases of unilateral involvement.

Materials and Methods

A retrospective study was conducted at the Department of Radiation Oncology, University Medical Center Mainz, on a cohort of 50 patients with unilateral SCC-CUP of the head and neck region treated between 2005 and 2019. 30 patients received bilateral and 20 received unilateral cervical radiotherapy. The majority (n = 38, 76 %) were treated with modern IMRT/ VMAT (Intensity-modulated Radiation Therapy/ Volumetric Modulated Arc Therapy) techniques.

Results

After a median follow-up of 64.5 months, locoregional recurrences occurred in 26 % of cases (n = 13/50), all of which were ipsilateral and predominantly within the volume of the previous irradiated CTV (clinical target volume) (85 %, n = 11/13). No patient treated unilaterally developed a contralateral recurrence in the neck. After 3 years, we observed 7 locoregional recurrences in the bilateral irradiated group (n = 7/30, 23 %), and 5 locoregional recurrences in the unilateral irradiated group (n = 5/20, 25 %). After 3 years, 12 patients had died in the bilateral irradiated group (n = 12/30, 40 %), and 7 in the unilateral irradiated group (n = 7/20, 35 %). 7 Patients showed distant metastases after 3 years in the bilateral irradiated group (n = 7/30, 23 %), and 2 in the unilateral irradiated group (n = 2/20, 10 %). Locoregional control (LRC) at 5 years was 66.2 % in the bilaterally irradiated group, and 70.0 % in the unilaterally irradiated group. Overall survival (OS) was 52.6 % (bilateral) and 64.0 % (unilateral). Distant metastasis-free survival (DMFS) was 74.7 % (bilateral) and 84.4 % (unilateral). No significant differences were observed in OS (p = 0.37), LRC (p = 0.91), and DMFS (p = 0.91) between the groups.Acute toxicity ≥ °2 accordingly CTCAE (Common Terminology Criteria of Adverse Events) was high with 97% while late toxicity ≥ °2 was moderate with 31%. There was no statistically significant difference between the group of unilateral and bilateral irradiated patients.

Conclusion

These data suggest that contralateral cervical irradiation may be of limited benefit in patients with SCC-CUP, as recurrences occured ipsilaterally, and predominantly within the area of prior irradiation. Unilateral irradiation seems to be adequate for carefully selected patients.

Management of unknown primary head and neck cancer with radiation therapy in the era of human papillomavirus (HPV): No longer cutting down the tree to get an apple

PURPOSE

Given the central role that radiation has in the management of head and neck squamous cell carcinoma of unknown primary origin, it is imperative to review how treatment paradigms have been refined and continue to evolve in the modern era.

METHODS AND MATERIALS

This study was designed based on the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) statement. A literature search of peer-reviewed publications was undertaken to identify works pertaining to the use of radiation for squamous cell carcinoma of unknown primary origin presenting as cervical lymph node metastases. Articles published from January 2002 to January 2023 with full text available on PubMed and restricted to the English language and human subjects were included. The full bibliographies of identified articles were reviewed and irrelevant studies were removed.

RESULTS

While such breakthroughs as intensity-modulated radiotherapy, positron emission tomography, biomarker testing with immune-histochemistry, and minimally invasive surgical techniques such as transoral robotic surgery have fundamentally changed the approach to this disease in recent decades, controversies still exist with respect to the manner in which radiation is delivered. Although the incidence of head and neck unknown primary cancer is relatively low, questions regarding the necessity of comprehensive radiation using the age-old standard method of targeting the bilateral necks and entire pharyngeal axis to encompass all putative sites of mucosal disease persist.

CONCLUSIONS

Prospective evidence is lacking, and the available studies have been complicated by such factors as the relatively limited sample sizes, as well as the variability in work-up, treatment, inclusion criteria, and follow-up. Regardless, advances in science and technology have ushered in more precise approaches with a high degree of customization, particularly given the increased proportion of patients presenting with human papillomavirus-related disease.

Long-term results of radio(chemo)therapy in metastatic carcinoma to cervical lymph nodes from an unknown primary. Adult Comorbidity Evaluation 27 score as a predictor of survival

PURPOSE

To evaluate the effectiveness and toxicity of curative (chemo)radiotherapy in patients with metastatic carcinoma to cervical lymph nodes from an unknown primary.

METHODS

Retrospective study of 90 consecutive patients, treated with curative radiotherapy from 2003 to 2018 (median age 59 years; current/former smokers 76%) was conducted. The distribution of nodal staging was as follows: N1: 12%, N2a: 21%, N2b: 43%, N2c: 10%, N3: 13%. In 62% of patients, neck dissection was performed before radiotherapy. Concomitant chemotherapy was given to 64% of patients.

RESULTS

The median follow-up of surviving patients was 86 months. The median total radiotherapy dose achieved was 70 Gy. The 5‑ and 10-year locoregional control were 84% in both cases, while 5‑ and 10-year distant control were 90% and 89%, respectively. A primary tumor in the head and neck area was detected in only 2 patients. No patient had an initial failure in the pharyngeal axis or contralateral cervical nodes. The 5‑ and 10-year overall survival were 55% and 42%, respectively. Severe early toxicity occurred in 71%; severe late toxicity in 33% of patients. Multivariate analysis demonstrated N‑status (hazard ratio [HR] 2.424; 95% confidence interval [CI] 1.121-5.241; p = 0.024) and comorbidity scores assessed by ACE-27 (Adult Comorbidity Evaluation; HR 3.058; 95% CI 1.489-6.281; p = 0.002) as two independent prognostic factors for overall survival.

CONCLUSION

The results of our work study demonstrate the high effectiveness of curative (chemo)radiotherapy on the pharyngeal axis and bilateral cervical nodes with long-term locoregional and distant control in 3/4 of the treated patients. N‑status and comorbidity scores were shown as strong prognostic factors influencing overall survival.

Proton Beam Therapy for Head and Neck Carcinoma of Unknown Primary: Toxicity and Quality of Life

Purpose

Proton radiation therapy (PRT) may offer dosimetric and clinical benefit in the treatment of head and neck carcinoma of unknown primary (HNCUP). We sought to describe toxicity and quality of life (QOL) in patients with HNCUP treated with PRT.

Patients and Methods

Toxicity and QOL were prospectively tracked in patients with HNCUP from 2011 to 2019 after institutional review board approval. Patients received PRT to the mucosa of the nasopharynx, oropharynx, and bilateral cervical lymph nodes with sparing of the larynx and hypopharynx. Patient-reported outcomes were tracked with the MD Anderson Symptom Inventory–Head and Neck Module, the Functional Assessment of Cancer Therapy–Head and Neck, the MD Anderson Dysphagia Inventory, and the Xerostomia-Related QOL Scale. Primary study endpoints were the incidence of grade ≥ 3 (G3) toxicity and QOL patterns.

Results

Fourteen patients (median follow-up, 2 years) were evaluated. Most patients presented with human papillomavirus–positive disease (n = 12, 86%). Rates of G3 oral mucositis, xerostomia, and dermatitis were 7% (n = 1), 21% (n = 3), and 36% (n = 5), respectively. None required a gastrostomy. During PRT, QOL was reduced relative to baseline and recovered shortly after PRT. At 2 years after PRT, the local regional control, disease-free survival, and overall survival were 100% (among 7 patients at risk), 79% (among 6 patients at risk), and 90% (among 7 patients at risk), respectively.

Conclusion

Therefore, PRT for HNCUP was associated with highly favorable dosimetric and clinical outcomes, including minimal oral mucositis, xerostomia, and dysphagia. Toxicity and QOL may be superior with PRT compared with conventional radiation therapy and PRT maintains equivalent oncologic control. Further prospective studies are needed to evaluate late effects and cost-effectiveness.

Patterns of Failure in Patients With Head and Neck Squamous Cell Carcinomas of Unknown Primary Treated With Chemoradiotherapy

Background:

To evaluate the patterns of failure in patients treated for head and neck carcinoma of unknown primary and to discuss treatment practices concerning radiotherapy target volumes definition and dose prescription.

Methods:

Eleven patients presenting a locoregional recurrence after head and neck carcinoma of unknown primary treatment with curative-intent radiochemotherapy performed between 2007 and 2017 in the departments of radiation oncology of 2 French cancer institutes. Images of the computed tomography scan or the magnetic resonance imaging performed at the time of the recurrence were fused with those of the simulation computed tomography scan to delimit a volume corresponding to the recurrence and to define the area of relapse compared to the volumes treated.

Results:

Irradiation was unilateral in 6 cases and bilateral in 5 cases. The median time to onset of recurrence was 7.24 months (extreme 3-67.7 months). Six patients had only a neck node recurrence, 3 had a neck node and subsequent primary recurrence, and 1 had only a median subsequent primary recurrence. Only 1 patient had synchronous distance progression to local recurrence. All neck node recurrences were solitary and ipsilateral. The subsequent primary recurrences were in the oropharynx in 3 cases and in the contralateral oral cavity in one case. All neck node recurrences were into the irradiated volume. The subsequent primary recurrences were either within or in border of the irradiated volumes. The median of the mean dose, received by neck node recurrences, was 69.9 Gy and that of the mean dose, minimum dose, maximum dose, and dose received by 95% of the volume of recurrence was 66.7 Gy. For the primary relapses, the median of the mean dose was 52.1 Gy and that of the mean dose, minimum dose, maximum dose, and dose received by 95% of the volume of recurrence was 39.9 Gy.

Conclusions:

All local nodal recurrences occurred at sites that received high radiotherapy doses and doses received by sites of eventual failure did not vary significantly from sites that remain in control.

Failure patterns of cervical lymph nodes in metastases of unknown origin according to target volume

Purpose

This study was aim to evaluate the patterns of failure according to radiotherapy (RT) target volume for cervical lymph nodes in metastases of unknown primary origin in head and neck region (HNMUO).

Materials and Methods

Sixty-two patients with HNMUO between 1998 and 2016 were retrospectively reviewed. We analyzed the clinical outcomes and primary site failure depending on the radiation target volume. The target volume was classified according to whether the potential head and neck mucosal sites were included and whether the neck node was treated involved side only or bilaterally.

Results

Potential mucosal site RT (mucosal RT) was done to 23 patients and 39 patients did not receive mucosal RT. Mucosal RT showed no significant effect on overall survival (OS) and locoregional recurrence (LRR). The location of primary site failure encountered during follow-up period was found to be unpredictable and 75% of patients with recurrence received successful salvage therapies. No significant differences in OS and LRR were found between patients treated to unilateral (n = 35) and bilateral neck irradiation (n = 21). Treatment of both necks resulted in significantly higher mucositis.

conclusions

We found no advantages in OS and LRR of patients with HNMUO when mucosal sites and bilateral neck node were included in the radiation target volume.

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.

Roles of Ki-67 and p16 as biomarkers for unknown primary head and neck squamous cell carcinoma

PURPOSE

Treatment guidelines have not been established for unknown primary head and neck squamous cell carcinoma (SCC). For these patients, chemoradiotherapy (CRT) can provide a better prognosis than that for patients with other head and neck cancers. The presence of HPV in the tumor is associated with a better outcome. However, not all patients with HPV-positive unknown primary head and neck SCC experience good treatment outcomes in actual clinical settings.

METHODS

We thus retrospectively determined the Ki-67 proliferation index and p16 expression status to assess the associations of these parameters with treatment outcomes of patients with unknown primary head and neck SCC.

RESULTS

The subjects were 13 patients who underwent CRT after surgery or excision biopsy between 1999 and 2016. The 2- and 5-year overall survival (OS) rate was 76.9% and 68.4%, respectively. The prognostic factor was age. There was no significant difference in survival between patients with a high Ki-67 vs. low Ki-67 or between patients with p16-positive vs. p16-negative metastases OS. However, all p16-positive patients with low Ki-67 showed good locoregional control.

CONCLUSIONS

The combination of ki67 expression and p16 expression status may allow prediction of local control more accurately than p16 expression status alone.

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

BACKGROUND

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

OBJECTIVES

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

MATERIAL AND METHODS

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

RESULTS

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

CONCLUSIONS

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

SIGNIFICANCE

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

GEORCC recommendations on target volumes in radiotherapy for Head Neck Cancer of Unkown Primary

Head Neck Cancer of Unknown Primary (HNCUP) is a rare condition, representing approximately 5-10% of all head neck cancers. Radiotherapy, adjuvant or radical, is usually employed in the treatment of those patients. To date, no specific guidelines for the optimal definition of the target volume to be irradiated have been published. In recent years, there have been advances in the knowledge of the molecular biology of HNCUP, its diagnostic imaging and the implementation of sophisticated radiotherapy techniques with enhanced precision in target localization and treatment delivery. These progresses have provided valuable information about the natural history of HNCUP that will allow for establishment of the best treatment for each patient, including standardized, consistent and reproducible target volumes definitions. Several recommendations regarding how to choose volumes when contouring HNCUP in clinical practice are reported, in order to achieve a high rate of loco-regional control while avoiding unnecessary toxicity.

[Advances in the management of cervical lymphadenopathies of unknown primary with intensity modulated radiotherapy: Doses and target volumes]

The definition of nodal and/or mucosal target volumes for radiation therapy for lymphadenopathies of unknown primary is controversial. Target volumes may include all nodal areas bilaterraly and be pan-mucosal or unilateral, selective, including the sole oropharyngeal mucosa. This review presents current recommendations in light of changes in the TNM classification, Human papillomavirus status and therapeutic advances. We conducted a systematic review of the literature with the following keywords: lymphadenopathy; head and neck; unknown primary and radiation therapy. There are no direct comparative studies between unilateral or bilateral nodal irradiation or pan-mucosal and selective mucosal irradiation. Contralateral lymph node failure rates range from 0 to 6% after unilateral nodal irradiation and 0 and 31% after bilateral irradiation. Occurrence of a mucosal primary varies between 0 and 19.2%. Initial clinical presentation and Human papillomavirus status are critical to define mucosal target volumes. Intensity-modulated radiotherapy is recommended (rather than three-dimensional irradiation) to avoid toxicities. Systemic treatments have similar indications as for identified primary head and neck cancers. Failures do not appear superior in case of unilateral nodal irradiation but comparative studies are warranted due to major biases hampering direct comparisons. Human papillomavirus status should be incorporated into the therapeutic strategy and practice-changing TNM staging changes will need to be evaluated.

A matched comparison of human papillomavirus-induced squamous cancer of unknown primary with early oropharynx cancer

OBJECTIVES/HYPOTHESIS

Patients with human papillomavirus (HPV)-induced cancer of unknown primary (CUP) are generally excluded from clinical trials, despite surgical series reporting detection rates of occult oropharynx primaries of >80%. We performed a matched-pair analysis to compare outcomes between T0N1-3M0 HPV+ CUP and T1-2N1-3M0 HPV+ oropharynx known primary (OPX).

STUDY DESIGN

Retrospective cohort study at a single institution.

METHODS

Patients with early T stage, node positive HPV+ OPX or CUP treated with curative intent between 1998 and 2016 were identified. For a subgroup of CUP patients with an unknown HPV status, we imputed HPV status and included patients with a >80% probability of being HPV+. Cohorts were matched based on patient demographics using a nearest neighbor propensity technique. After matching, patients were grouped according to either a favorable or unfavorable risk stratification designations per current NRG Oncology clinical trial enrollment criteria. Disease-free survival (DFS) and overall survival (OS) were calculated using Kaplan-Meier analysis.

RESULTS

Of 298 patients with T1-2N1-3 OPX, 48 were matched to 48 HPV+ CUP patients (32 with confirmed and 16 imputed HPV status). Median follow-up for CUP (34.1 months) and OPX (27.8 months) patients were similar (P = .23).There were no significant differences between the CUP and OPX groups for 3-year DFS (89% vs. 85%, P = .44), and 3-year OS (91% vs. 91%, P = .11), respectively.

CONCLUSIONS

Patients with T0N+M0 HPV-induced CUP have similar survival outcomes to matched patients with T1-2N+M0 HPV+ OPX. These patients can reasonably be included in clinical trials investigating the role of treatment deintensification and risk stratified similar to patients with early-stage known primary OPX cancer.

LEVEL OF EVIDENCE

4. Laryngoscope, 128:1379-1385, 2018.

Unknown primary head and neck squamous cell carcinoma in the era of fluorodeoxyglucose-positron emission tomography/CT and intensity-modulated radiotherapy

BACKGROUND

The diagnosis and treatment of head and neck carcinoma of unknown primary (CUP) have changed with the introduction of fluorodeoxyglucose-positron emission tomography (FDG-PET)/CT and intensity-modulated radiotherapy (IMRT), with potential implications for outcome.

METHODS

We conducted a retrospective analysis of 80 patients with head and neck CUP who were PET-staged and treated with curative intention using IMRT between 2006 and 2016 in the Netherlands Cancer Institute. Patient, tumor, and treatment demographics were recorded and oncologic outcomes were analyzed.

RESULTS

Local control was 100% in mucosal irradiated patients. Regional control was 90%. Ten patients developed distant metastases, which were associated with N3, extracapsular extension (ECE) and lower neck positive lymph nodes. Overall survival (OS) at 5 years was 62% and disease-specific survival was 78%. ECE, N3 neck, multiple levels of positive lymph nodes, and positive lymph nodes in the lower neck were associated with worse prognosis.

CONCLUSION

Locoregional outcome of head and neck CUP managed with modern techniques is good. Future research needs to focus on reducing toxicity and patients prone for distant metastasis.

A Nordic survey on the management of head and neck CUP

CONCLUSION

The management of Head and Neck Cancer of Unknown Primary (HNCUP) patients varies both between centres within and also between the Nordic countries. This study contributes to a continuing discussion of how to improve the accuracy of diagnosis and quality of treatment of HNCUP patients.

OBJECTIVES

The initiative for this study was based on the lack of common guidelines for diagnostic procedures and for treatment of HNCUP patients in the Nordic countries constituting a region having a rather homogeneous population.

METHOD

A structured questionnaire was sent to all university hospitals in the five Nordic countries.

RESULTS

Four of the five Nordic countries use either national guidelines or specific protocols when handling HNCUP. The main diagnostic tools are PET-CT, fine needle aspiration, endoscopic evaluation with biopsies, and most often bilateral tonsillectomy. At 21 of 22 university hospitals the treatment decision is made at a multidisciplinary conference. Three of seven Swedish centres use only radiotherapy or chemoradiotherapy to treat N+ HNCUP patients. Robotic surgery for biopsy of the tongue base is beginning to become an alternative to targeted biopsies in Sweden and Finland. Narrow Band Imaging is used only in Finland.