Sex-Specific Survival and Treatment Delay in Oropharyngeal Squamous Cell Carcinoma

OBJECTIVE

As the majority of oropharyngeal squamous cell carcinoma (OPSCC) is diagnosed in males, outcomes among females are not well-characterized. We identify sex-specific factors in OPSCC to refine female prognostication.

STUDY DESIGN

Retrospective cohort.

SETTING

National Cancer Database (NCDB).

METHODS

OPSCC cases from the 2004 to 2019 NCDB were identified. Sociodemographic, clinical, and treatment characteristics (including timing between diagnosis and treatment administration) were compared between sexes. Multivariable Cox proportional hazard regression models were constructed to characterize survival in overall and female-only cohorts. Similar multivariable binomial logistic regression and survival models were constructed to assess odds of treatment delays and their effects on survival, respectively.

RESULTS

A total of 192,973 OPSCC patients were identified; 36,695 (19%) were female. Females had more human papillomavirus (HPV) negative, lower clinical T and N stage, and higher comorbidity disease. Females experienced lower survival in HPV negative (hazard ratio, HR = 1.11, P < .001) but not HPV-positive disease. Females were more likely to have any treatment initiated over the median of 28 days (odds ratio, OR = 1.04, P = .014) or delays in adjuvant radiotherapy initiation over 6 weeks (OR = 1.11, P = .032). Treatment delay over 60 days (HR = 1.17, P = .016) and delay in adjuvant therapy initiation (HR = 1.24, P = .02) were associated with worse survival among females.

CONCLUSION

In one of the largest analyses of OPSCC, females had poorer survival than males, specifically in HPV-negative disease, despite presentation with less advanced disease. Notably, delays in any treatment initiation and adjuvant radiotherapy initiation were more likely in HPV-negative women and associated with worse survival, highlighting potential systemic weaknesses contributing to poor prognosis among females.

Baseline mutational profiles of patients with carcinoma of unknown primary origin enrolled in the CUPISCO study

BACKGROUND

Patients with unfavorable carcinoma of unknown primary origin (CUP) have an extremely poor prognosis of ∼1 year or less, stressing the need for more tailored treatments, which are currently being tested in clinical trials. CUPISCO (NCT03498521) was a phase II randomized study of targeted therapy/cancer immunotherapy versus platinum-based chemotherapy in patients with previously untreated, unfavorable CUP, defined as per the European Society for Medical Oncology guidelines. We present a preliminary, descriptive molecular analysis of 464 patients with stringently diagnosed, unfavorable CUP enrolled in the CUPISCO study.

MATERIALS AND METHODS

Genomic profiling was carried out on formalin-fixed, paraffin-embedded tissue to detect genomic alterations and assess tumor mutational burden and microsatellite instability.

RESULTS

Overall, ∼32% of patients carried a potentially targetable genomic alteration, including PIK3CA, FGFR2, ERBB2, BRAFV600E, EGFR, MET, NTRK1, ROS1, and ALK. Using hierarchical clustering of co-mutational profiles, 10 clusters were identified with specific genomic alteration co-occurrences, with some mirroring defined tumor entities.

CONCLUSIONS

Results reveal the molecular heterogeneity of patients with unfavorable CUP and suggest that genomic profiling may be used as part of informed decision-making to identify the potential primary tumor and targeted treatment options. Whether stringently diagnosed patients with unfavorable CUP benefit from targeted therapies in a similar manner to those with matched known primaries will be a key learning from CUPISCO.

Report on a case of liver-originating malignant melanoma of unknown primary

Malignant melanoma (MM) frequently occurs in the skin or mucosa, whereas malignant melanoma of unknown primary (MUP) is diagnosed in patients with lymph nodes or visceral organs as the site of origin, where it is challenging to detect the primary lesion by comprehensive examination. MUP is possibly related to the spontaneous regression of the primary lesion. In addition, primary hepatic melanoma (PHM) usually refers to the primary MM occurring in the liver, with no typical primary lesions and no manifestations of tumor metastasis. A 61-year-old male patient with liver as the site of origin was diagnosed with MM by Melan-A, HMB-45, and S-100 immunohistochemistry staining of liver biopsy tissue. Based on a comprehensive examination, no basis was found for melanoma in sites such as the skin, mucosa, five sense organs, brain, digestive tract, respiratory tract, or genitalia, and the patient was subsequently diagnosed with MUP. MMs require a comprehensive inspection, beginning with the liver, to search for the primary lesion; if the primary lesion is not found, the possibility of PHM or MUP should be considered.

Survival Outcome in True Carcinoma of Unknown Primary (tCUP) with p16 + Cervical Metastasis

Introduction  Age and lymph node ratio have been attributed as independent predictors for survival and recurrence in carcinoma of unknown primary (CUP). Objective  The purpose of this study was to analyze the prognostic value of p16 overexpression for CUP in the absence of true primary (TP). Methods  The study involved 43 patients who underwent therapeutic lymph node dissection (LND) from 2000 to 2015 after all the diagnostic work up for CUP. Immunohistochemistry for p16 overexpression was performed. Cox proportional hazard regression analysis was used to analyze the prognostic impact on 5-year overall survival (OS) and recurrence-free survival (RFS). Results  The male-to-female ratio was 5.1:1, with a median age of 62 years. The clinicopathological data, except for p16 overexpression, did not differ significantly in terms of 5-year OS and RFS. The Cox regression analysis proposed p16 positivity to be an independent prognosticator of regional recurrence-free survival (RRFS) (hazard ratio [HR] 6.180, p  = 0.21). The median time to recurrence and death were 10 and 25 months, respectively. Conclusion  Cervical metastasis with p16 overexpression is a significant prognostic factor of improved RFS after surgery in CUP. The prognostic significance of lymph node p16 positivity should be further studied.

Analysis of Prognoses according to Breast MRI Results in Patients with Axillary Lymph Node Metastases from an Unknown Primary Origin

PURPOSE

To compare the prognosis of patients with axillary adenocarcinoma from an unknown primary (ACUPax) origin with negative MRI results and those with MRI-detected primary breast cancers.

MATERIALS AND METHODS

The breast MRI images of 32 patients with ACUPax without signs of primary breast cancer on mammography and ultrasound (US) were analyzed. Spot compression-magnification mammography and second-look US were performed for the area of MRI abnormality in patients with positive results; any positive findings corresponding to the MRI abnormality were confirmed by biopsy. If suspicious MRI lesions could not be localized on mammography or US, MR-guided biopsy or excision biopsy after MR-guided localization was performed. We compared the prognosis of patients with negative breast MRI with that for patients with MRI-detected primary breast cancers.

RESULTS

Primary breast cancers were confirmed in 8 (25%) patients after breast MRI. Primary breast cancers were not detected on MRI in 24 (75%) patients, including five cases of false-positive MRI results. Twenty-three patients underwent axillary lymph node dissection (ALND) followed by whole breast radiation therapy (WBRT) and chemotherapy (n=17) or subsequent chemotherapy only (n=2). Recurrence or distant metastasis did not occur during follow up in 7/8 patients with MRI-detected primary breast cancers and 22/24 patients with negative MRI results. Regional recurrence or distant metastasis did not occur in any MR-negative patient who received adjuvant chemotherapy after ALND and WBRT.

CONCLUSION

The prognoses of MR-negative patients with ACUPax who received ALND and WBRT followed by chemotherapy were as good as those of patients with MRI-detected primary breast cancers.

A Case of Metastatic Papillary Thyroid Carcinoma in Neck Lymph Nodes Without Primary Tumor in Thyroid Gland

Metastatic papillary thyroid carcinoma in the lymph nodes without a primary tumor in the thyroid gland is rarely reported. We report the case of a 63-year-old male who had a left neck level II palpable mass. A left cervical mass had previously undergone 2 central needle biopsies, but only atypical cells had been identified. His prior medical history included surgical treatment for prostate cancer 11 years ago. There was no suspicious primary tumor in the endoscopic examination. After the excisional biopsy, the pathologic finding was metastatic papillary carcinoma from the thyroid, and there were no aberrant findings in the thyroid sonography. The patient underwent a complete thyroidectomy, bilateral central neck dissection (CND), and left level IV dissection, along with postoperative radioactive iodine (RAI) therapy. No thyroid lesion and no more positive lymph nodes were found in the final pathology report. Three months later, a radioiodine nuclear scan was performed, although it revealed no abnormal iodine uptake.

Metastatic Gastric Mucosal Melanoma: A Rare Case Presenting With Diffuse Gastric Polyposis

We report a 66-year-old Chinese lady who presented with a three-month history of postprandial vomiting, early satiety, anorexia and weight loss, and significant physical findings of hepatomegaly and ascites. Gastroscopy revealed gastric polyposis with both hyperpigmented and unpigmented lesions over the gastric fundus, body, and proximal antrum, biopsies of which yielded malignant melanoma histologically. Cross-sectional imaging with CT also demonstrated extensive hepatic and bony metastases. No cutaneous or ocular primary was detected. She was treated with a combination of ipilimumab and nivolumab but developed interval progression of hepatic metastases after two cycles of immunotherapy. The patient eventually succumbed two months after diagnosis.

Survival after lymphadenectomy of nodal metastases from melanoma of unknown primary site

Although the vast majority of melanomas have a primary site, 3%-4% of all melanomas in distant sites display no known primary site (MUP). This phenomenon is not fully understood and various hypotheses have been introduced. The prognostic significance of MUP has been unclear, with some studies showing no survival benefit while others find improved survival compared to stage-matched patients with melanoma of known primary site (MKP). Between 1997 and 2014, 864 patients underwent an en bloc resection of clinical nodal metastases at a referral centre for metastatic melanoma in Norway. The MUP (n = 113) and MKP (n = 751) patients were graded with stage III or IV. The overall survival (OS) was calculated with the Kaplan-Meier method, and multivariate analysis identified factors of significance for the two groups. A significant five-year OS emerged for stage III, MUP = 58% and 42% for MKP, but not for stage IV. The five-year relapse-free survival (RFS) was 41% and 31% for MUP and MKP respectively (p = 0.049). The statistically significant inter-group differences (MUP/MKP) were observed in the univariate and multivariate analyses of age, gender, number of affected nodes, tumour size and perinodal growth within stage III and tumour size within stage IV. After regional lymphadenectomy, MUP patients with clinical nodal metastases had a better outcome than MKP patients. This finding supports the theory that an endogenously mediated immune response may promote the regression of a cutaneous melanoma.

Reconceptualizing the clinicopathological features, locoregional therapy and prognostic factors of occult breast cancer in the era of molecular subtyping

To evaluate the clinical features, molecular subtypes, therapeutic strategies, and prognostic factors of occult breast cancer (OBC). Patients with T0-3/N1-3/M0 breast cancer diagnosed in 2010-2018 (n = 114,303, including 691 with OBC) were retrieved from the Surveillance, Epidemiology, and End-Results (SEER) database. The endpoints were overall survival (OS) and breast cancer-specific survival (BCSS). Compared with non-OBC, OBC presented significantly more adverse clinicopathological prognostic features. More patients with OBC underwent breast-conserving treatment (BCT) and less had axillary lymphadenectomy (ALD). Outcomes were more favorable in OBC cases compared with non-OBC cases (p = .002 for OS, p = .002 for BCSS). Triple-negative (TNBC) and HER2-enriched were the subtypes with the worst prognosis in OBC (p < .05). Prognosis was better for triple-negative OBC compared with the same subtype of non-OBC. N-stage was not a strong prognostic indicator of OBC (p > .05 for OS). Cases who underwent systemic chemotherapy alone without surgery had the worst prognosis among OBC patients. For locoregional therapy, mastectomy and radiotherapy could confer survival advantage; standard axillary lymph node dissection (ALND) and positive lymph node dissection (PLND) contributed notably to OS in OBC patients. Both OS and BCSS were better in OBC cases compared with non-OBC. Systemic chemotherapy alone without surgery is not appropriate for OBC treatment, and mastectomy plus standard axillary surgery is recommended. Patients with hormone receptor-positive and low burden of axillary lymph node metastasis may be spared from radiotherapy after undergoing standard axillary lymphadenectomy.

Reporting a Case of Cervical Vertebral Body Primary Malignant Melanoma-A Rare Entity

Melanomas of vertebral body are usually metastatic lesions. Isolated vertebral body melanomas are rare may be due to unknown primary. Only threesuch cases havebeen reported in literature. We are reporting a 30-year-old female presented with progressive quadriparesis and bladder involvement. On evaluation, an extradural lesion at the C4-5 level with the destruction of C4 vertebral body and anterior in the prevertebral space seen with areas of blooming. The patient underwent surgery and biopsy was suggestive of melanoma. On further evaluation, we could find any other lesion in the body. The lesion can be either metastatic with unknown primary or primarily arising from vertebrae. Primary vertebral body melanomas are rare, surgical decompressions followed by immunotherapy may prolong the survival in this patients.

Hypothesised cutaneous sites of origin of stage III melanomas with unknown primary: A multicentre study

Based on molecular evidence that melanomas with unknown primary (MUPs) arise from the skin, we hypothesised that sites of MUPs are disproportionately on trunk and lower limbs, sites that are not readily visible to patients and clinicians. We tested this hypothesis by inferring the anatomic site of origin of MUPs from the corresponding known cutaneous sites of melanoma patients with known primary tumours (MKPs). We analysed data from three separate cohorts of patients from Brisbane, Australia (n = 236); Manchester, UK (n = 51) and Padova, Italy (n = 33), respectively, who first presented with stage III melanoma with lymph node metastases. We matched two MKP patients to each MUP patient based on lymph node dissection (LND) site, age and sex, and imputed cutaneous sites of origin of MUPs from their two matched MKPs for study countries, giving two possible sites for each MUP per centre. Overall, results showed that MUP patients were predominantly male, and trunk was the most likely origin, comprising around a third to a half of MUPs across the three cohorts. The remaining MUP inferred sites varied by country. In the Australian cohort, the legs accounted for a third of imputed sites of MUPs, while in the UK and Italian cohorts, the most frequent site was the arms followed by the legs. Our findings suggest the need for regular and thorough skin examination on trunk and limbs, especially in males, to improve early detection of cutaneous melanoma and reduce the risk of metastatic disease at the time of presentation.

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.

Merkel cell carcinoma of unknown primary: Clinical presentation and outcomes

BACKGROUND

Merkel cell carcinoma (MCC) is a rare, aggressive cutaneous malignancy that usually occurs in the head/neck or extremities. However, there are reports of MCC developing in the lymph nodes or parotid gland without evidence of a primary cutaneous lesion.

METHODS

We reviewed 415 patients with biopsy-proven MCC. Patients with MCC of unknown primary (n = 37, 9%, MCCUP) made up the study cohort. The primary endpoints of the study were rate of recurrence, disease-free survival, and overall survival.

RESULTS

Patients with MCCUP presented with tumors in lymph nodes (n = 34) or parotid gland (n = 3). Nodal disease was most commonly detected in the inguinal/external iliac (n = 15) or axillary (n = 14) regions. The mean age at diagnosis was 70 years and 24% were female. Patients presented with distant metastases in 24.3% of cases. Patients with stage IIIA disease treated with regional lymph node dissection (RLND) had a lower risk of disease recurrence (hazard ratio 0.26, p = 0.046). Recurrence-free survival was 59.3% at 5 years. Disease-specific survival was 63.3% at 5 years.

CONCLUSION

Patients with MCCUP have a high risk of recurrence and mortality. The optimal treatment for MCCUP has yet to be elucidated, although therapeutic RLND appears beneficial for these patients.

Oral metastasis as the first indication of undiscovered malignancy at a distant site: A systematic review of 413 cases

This systematic review is the first to provide evidence regarding demographic, clinical, and imaging characteristics, as well as information related to survival, of patients with oral and maxillofacial metastases of occult primary tumors. Case reports, case series, and cross-sectional studies were included. Ten databases were searched. The risk of bias was assessed using the Joanna Briggs Institute appraisal tools. Overall, 353 articles (413 patients) were included. Statistically significant associations between survival and multiplicity of metastatic foci, and between each of the main primary sites and some features of the oral lesions were observed. Some clinical and imaging characteristics can help dentists in raising diagnostic suspicions and also in relating to plausible primary sites. Early diagnosis of oral and maxillofacial metastases can positively affect the survival rate when they are the only focus of dissemination, conferring an important role on the dentist.

Cancer-of-Unknown-Primary-Origin: A SEER-Medicare Study of Patterns of Care and Outcomes among Elderly Patients in Clinical Practice

Simple Summary

Cancer-of-unknown-primary-origin (CUP) is challenging to diagnose and treat, and little is known about its diagnostic work-up, treatment, and outcomes in routine healthcare. We examined data from elderly patients (at least 66 years old) diagnosed with CUP in real-world US clinical practice, using the Surveillance, Epidemiology, and End Results–Medicare-linked database. Only half of elderly patients with CUP received all three diagnostic work-up procedures (biopsy, immunohistochemistry, and imaging), as recommended by guidelines. Patients who received all three diagnostic work-up procedures were more likely to receive any type of anticancer treatment, and patients who did not receive full diagnostic work-up had shorter median overall survival, particularly with increasing age. Overall, these results suggest that further studies are needed to understand why many patients given a diagnosis of CUP do not receive complete diagnostic work-up or treatment. Further research into improving diagnostic work-up and treatment effectiveness in patients diagnosed with CUP is required.

Abstract

Knowledge of contemporary patterns of cancer-of-unknown-primary-origin (CUP) diagnostic work-up, treatment, and outcomes in routine healthcare is limited. Thus, we examined data from elderly patients diagnosed with CUP in real-world US clinical practice. From the Surveillance, Epidemiology, and End Results–Medicare-linked database, we included patients ≥ 66 years old with CUP diagnosed between 1 January 2013 and 31 December 2015. We analyzed baseline demographics, clinical characteristics, methods of diagnostic work-up (biopsy, immunohistochemistry, imaging), treatment-related factors, and survival. CUP diagnosis was histologically confirmed in 2813/4562 patients (61.7%). Overall, 621/4562 (13.6%) patients received anticancer pharmacotherapy; among these, 97.3% had a histologically confirmed tumor and 83.1% received all three procedures. Among those with a histologically confirmed tumor, increasing age, increasing comorbidity score, not receiving all three diagnostic measures, and having a not-further specified histologic finding of only ‘malignant neoplasm’ were all negatively associated with receipt of anticancer pharmacotherapy. Median overall survival was 1.2 months for all patients. Median time between CUP diagnosis and treatment initiation was 41 days. Limited diagnostic work-up was common and most patients did not receive anticancer pharmacotherapy. The poor outcomes highlight a substantial unmet need for further research into improving diagnostic work-up and treatment effectiveness in CUP.

Molecular deciphering of primary liver neuroendocrine neoplasms confirms its distinct existence with foregut-like profile

Isolated hepatic localizations of neuroendocrine tumors (NETs) are generally considered as metastatic NETs of unknown primary but could correspond to primary hepatic NETs (PHNETs), a poorly explored entity. We aimed to describe the clinicopathological and molecular features of PHNETs and compare them with other primary NETs. We assembled a retrospective cohort of patients managed for hepatic localization of NET without extra-hepatic primary tumor after exhaustive clinical, imaging and immunohistochemical characterization. We performed whole-exome sequencing with mutational and copy number analysis. Transcriptomic profiles were compared to pancreatic (n=31), small-bowel (n=22) and lung (n=15) NETs using principal component analysis, unsupervised clustering and gene-set enrichment analysis. Among 27 screened patients, 16 had PHNET (solitary tumor in 63%, median size 11 cm, G2 NETs in 81%) following clinical and pathological review. DNA analyses showed "foregut-like" genomic profiles with frequent alterations in pathways of Fanconi DNA repair (75%), histone modifiers (58%), adherens junctions (58%) and cell cycle control (50%). The most frequently involved genes were KMT2A (58%), ATM (42%), CDH1, CDKN2C, FANCF and MEN1 (33% each). Transcriptomic analyses showed that PHNETs clustered closer to foregut (pancreatic, lung) NETs than to midgut (small-bowel) NETs, while remaining a distinct entity with specific profile. Assessment of potentially predictive biomarkers suggested efficacy of treatments usually active in foregut NETs. In conclusion, PHNETs display a foregut-like molecular profile distinct from other types of NETs, with recurrent molecular alterations. Upon exhaustive work-up to exclude unrecognized primary tumor, PHNETs should not be considered metastatic NETs from an unknown primary. This article is protected by copyright. All rights reserved.

Effective examination methods for identifying the primary origins of metastatic bone tumors of unknown primary origin during the initial visit: A retrospective chart review study

Objective:

To provide appropriate treatment for patients, early diagnosis of the primary origin of skeletal metastases of unknown primary origin is important. This study aimed to assess the examination strategy effective for identifying the primary origin of skeletal metastases of unknown primary origin.

Methods:

Sixty-one patients with skeletal metastases of unknown primary origin were reviewed. The primary origin was examined via physical examination, blood test including tumor markers, chest radiography, thoracoabdominal computed tomography scan, positron emission tomography–computed tomography scan, metastatic lesion biopsy, and other assessments. Examination methods considered effective for the diagnosis of the primary origin in a specific type of cancer were investigated.

Results:

The lung was the most common primary origin site, followed by the lymph nodes, prostate, and breast. Meanwhile, biopsy was the most effective examination, followed by positron emission tomography–computed tomography scan and thoracoabdominal computed tomography scan. Blood tests are useful for detecting hematological malignancies and prostate cancer. Computed tomography scans can be used to identify cancers in the lung, breast, and kidney, which are the common primary origins. Forty-one (67.2%) of the 61 patients with skeletal metastases of unknown primary origin were diagnosed via the first four steps, that is, physical examination, blood test, chest radiography, and thoracoabdominal computed tomography scan. Finally, two patients were diagnosed with skeletal metastases of unknown primary origin.

Conclusion:

The examination steps used in this study, including physical examination, blood test including tumor markers, chest radiography, thoracoabdominal computed tomography scan, positron emission tomography–computed tomography scan, biopsy, and other assessments were effective in determining the primary origin of skeletal metastases of unknown primary origin during the initial visit.

Metastatic Neuroendocrine Neoplasms of Unknown Primary: Clues from Pathology Workup

Simple Summary

While most neuroendocrine neoplasms are indolent and slow-growing tumors, subsets of cases will spread beyond the tissue of origin. Given the rather slow progress, some lesions are incidentally discovered as metastatic deposits rather than primary masses. In these cases, a biopsy is often taken to allow the pathologist to identify the tumor type and possibly the primary tumor site via microscopic examination. In this review, the authors present a simplified guide on how to approach metastatic neuroendocrine tumors from a pathologist’s perspective.

Abstract

Neuroendocrine neoplasms (NENs) are diverse tumors arising in various anatomical locations and may therefore cause a variety of symptoms leading to their discovery. However, there are instances in which a NEN first presents clinically as a metastatic deposit, while the associated primary tumor is not easily identified using conventional imaging techniques because of small primary tumor sizes. In this setting (which is referred to as a “NEN of unknown primary”; NEN-UP), a tissue biopsy is often procured to allow the surgical pathologist to diagnose the metastatic lesion. If indeed a metastatic NEN-UP is found, several clues can be obtained from morphological assessment and immunohistochemical staining patterns that individually or in concert may help identify the primary tumor site. Herein, histological and auxiliary analyses of value in this context are discussed in order to aid the pathologist when encountering these lesions in clinical practice.

Cutaneous metastasis of occult breast cancer: a case report

Occult breast cancer (OBC) is characterized by metastatic presentation of undetectable breast tumor on imaging exams. OBC is a rare disease (accounting for 0.3% to 1.0% of all breast cancers) that represents a major diagnostic challenge. The aim of this study was to report a case of OBC with primary presentation of multiple cutaneous metastases with subsequent emergence of bone metastasis. A 70-year female patient had multiple cutaneous metastatic lesions in the left cervical region, left breast, left axillary region, left subscapular region, in three chirodactylus of the right hand and three chirodactylus of the left hand. Imaging tests (mammogram, ultrasonography and magnetic resonance imaging of the breast) did not show alterations. Biopsy, histology sections and immunohistochemistry of the left cervical cutaneous lesion were compatible with OBC. After two years of anastrozole treatment (1mg/day), there was regression of all cutaneous lesions and stabilization of bone metastasis. OBC has a better prognosis. It may exhibit spontaneous regression or respond to less aggressive treatment strategies, as described in this case.

Tumor detection with transoral use of flexible endoscopy for unknown primary head and neck cancer

OBJECTIVES

With the advent of new optical technologies, early pharyngolaryngeal cancerous lesions can be better visualized. Although the conventional transnasal approach offers great views of the hypopharynx and larynx, the visualization of the oropharynx and palatine tonsils is limited. Through the transoral insertion of a flexible video-laryngoscope, direct views of the oropharynx and oral cavity can be obtained. Thus, transoral examination may contribute to primary detection of cancers of unknown primary (CUP).

METHODS

Eighty-five CUP patients from Tokai University were included retrospectively in this study, from 2006 to 2017. Starting in 2010, we employed the transoral examination in addition to our conventional method. The primary detection rates were compared before and after 2010. Oropharyngeal primaries were further analyzed for tumor subsite and p16 status.

RESULTS

The overall primary detection rate did not improve with the addition of transoral examination. However, greater numbers of oropharyngeal primaries were detected. The oropharyngeal lesions detected by transoral examination were mainly p16 positive, located on the palatine tonsil.

CONCLUSION

Transoral examination is a noninvasive, easy method to adopt in an outpatient setting, and a promising technique to improve tumor detection in this era of human papillomavirus-associated head and neck cancers.

LEVEL OF EVIDENCE

3.

Cancer of unknown primary in a mare: case report and comparative pathology review

A 25-y-old Percheron mare was admitted to the teaching hospital because of lethargy and intractable dyspnea. Thoracoabdominal ultrasound examination identified severe peritoneal effusion, mild bilateral pleural effusion, and a diffuse pulmonary nodular pattern. Cytology of peritoneal fluid revealed a hypercellular sample with clusters of neoplastic polygonal cells and admixed macrophages. Euthanasia was followed by postmortem examination; marked bi-cavitary effusion was present, and innumerable up to 4-cm diameter, round-to-floriform nodules were diffusely evident throughout serosal surfaces as well as the pulmonary and hepatic parenchyma. Disseminated adenocarcinoma, predominantly affecting lung and liver with widespread serosal implantation, was confirmed on light microscopy. Neoplastic cells had strong immunolabeling for pancytokeratin and lacked immunoreactivity to vimentin, napsin A, and Pax8. Cytokeratin 7 and thyroid transcription factor-1 were non-contributory given absent and inconsistent internal control reactivity, respectively. Such results, combined with the lack of a major mass that would indicate a primary site, were supportive of carcinoma of unknown primary site, which remains a conundrum in human oncology, and is poorly explored in veterinary medicine, mainly as a result of clinical and diagnostic limitations.

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.

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.

Merkel Cell Carcinoma of Unknown Primary: Immunohistochemical and Molecular Analyses Reveal Distinct UV-Signature/MCPyV-Negative and High Immunogenicity/MCPyV-Positive Profiles

Simple Summary

Merkel cell carcinomas (MCCs) of unknown primary are defined as deep-seated tumors without an associated cutaneous tumor. Although the distinction has important clinical implications, it remains unclear whether these tumors represent primary tumors of lymph nodes or metastatic cutaneous primaries. We compared the immunohistochemical profiles of four groups of Merkel cell carcinomas (virus-positive and virus-negative unknown primary tumors and virus-positive and virus-negative cutaneous tumors) and performed molecular studies on the unknown primary tumors. Virus-positive and virus-negative Merkel cell carcinomas of unknown primary (MCC-UPs) exhibited an immunoprofile similar to virus-positive and virus-negative primary cutaneous MCCs, respectively. Similar to primary cutaneous Merkel cell carcinomas, virus-negative unknown primary tumors exhibited UV signatures and frequent high tumor mutational burdens, whereas few molecular alterations were noted in virus-positive tumors. Although additional studies are warranted for the virus-positive cases, our findings are supportive of a cutaneous metastatic origin for virus-negative Merkel cell carcinomas of unknown primary.

Abstract

Background: Merkel cell carcinomas of unknown primary (MCC-UPs) are defined as deep-seated tumors without an associated cutaneous tumor. Although the distinction has important clinical implications, it remains unclear whether these tumors represent primary tumors of lymph nodes or metastatic cutaneous primaries. Methods: We compared the immunohistochemical profiles of four groups of MCCs (Merkel cell polyomavirus (MCPyV)-positive UP, MCPyV-negative UP, MCPyV-positive known primary (KP), and MCPyV-negative KP) using B-cell and pre-B-cell markers, cell cycle regulating proteins, follicular stem cell markers, and immune markers, and performed next generation and Sanger sequencing. Results: Virus-positive and virus-negative MCC-UPs exhibited an immunoprofile similar to virus-positive and virus-negative primary cutaneous MCCs, respectively. MCC-UP tumors (both virus-positive and -negative) were immunogenic with similar or even higher tumoral PD-L1 expression and intratumoral CD8 and FoxP3 infiltrates in comparison to MCPyV-positive cutaneous tumors. In addition, similar to primary cutaneous MCCs, MCPyV-negative MCC-UPs exhibited UV signatures and frequent high tumor mutational burdens, whereas few molecular alterations were noted in MCPyV-positive MCC-UPs. Conclusions: Our results showed distinct UV-signatures in MCPyV-negative tumors and high immunogenicity in MCPyV-positive tumors. Although additional studies are warranted for the MCPyV-positive cases, our findings are supportive of a cutaneous metastatic origin for MCPyV-negative MCC-UP tumors.

FDG-PET-CT/MRI in head and neck squamous cell carcinoma: Impact on pretherapeutic N classification, detection of distant metastases, and second primary tumors

BACKGROUND

To assess the effect of 18-fluorodeoxyglucose positron emission tomography (FDG-PET) in the pretherapeutic staging of N classification, detection rate of distant metastases, and second primaries.

METHODS

Retrospective study on patients with head and neck carcinoma. We compared pretherapeutic N classification by ultrasound, computed tomography (CT)/magnetic resonance imaging (MRI), and FDG-PET-CT/MRI.

RESULTS

A change in the N classification due to FDG-PET-CT/MRI was observed in 116 patients (39.5%) compared to N classification by ultrasound and fine-needle aspiration cytology. Patients with advanced nodal classification (>N2a) were more likely to be reclassified. Distant metastases were detected in 19 patients and a total of 36 second primaries were diagnosed by FDG-PET-CT/MRI. Detection of distant metastases was more likely in regional advanced disease (>N2a). Smokers (>10 py) had a significantly higher risk of second primary.

CONCLUSION

FDG-PET-CT/MRI leads to a significant change in pretherapeutic N classification. The cumulative incidence of distant metastases and second primaries was 18.7%.

Survival and therapeutic response in patients with melanoma of unknown and known primary: a single-centre retrospective analysis

BACKGROUND

The survival of patients with melanoma of unknown primary (MUP) is proposed to be more favourable than that for melanoma of known primary (MKP). This may be due to an enhanced initial immune response in patients with MUP, which could also affect the efficacy of immunotherapy in advanced disease.

OBJECTIVES

The present study compared therapeutic outcome and survival in Stage III and IV MUP and MKP.

RESULTS

Medical records of 67 MUP and 536 MKP patients were reviewed. Median overall survival (OS) in Stage III patients was 77 months versus 54 months in patients with MUP and MKP, respectively (p = 0.11). Median OS was prolonged in MUP patients receiving adjuvant first-line ipilimumab (p = 0.14). In contrast, OS tended to be more favourable in patients with MKP after palliative first-line ipilimumab treatment (p = 0.16). Yet, no statistically significant differences in OS were detected between the groups. Moreover, survival after anti-PD-1-antibody treatment was similar in patients with MUP and MKP.

CONCLUSION

Overall, we observed similar survival outcomes after immunotherapy in patients with MUP and MKP. These findings provide no evidence of difference in responsiveness to immunotherapy between patients with MUP and MKP.

Role of Tonsillectomy in the Management of Carcinomas of Unknown Primary of the Head and Neck: A Retrospective Study Based on p16 Analysis

Purpose

To evaluate the impact of tonsillectomy on the detection of the primary tumor, based on p16 immunohistochemistry analysis, in patients with cervical unknown primary of squamous cell carcinoma (SCC-CUP).

Methods

This was a retrospective study of 63 patients, included from January 2008 to December 2017 in a single institution. All patients had an initial assessment with physical examination, CT scan of the neck and chest, whole body FDG-PET CT, and endoscopy under general anesthesia, which failed to determine the primary tumor.

Results

Forty-seven out of the 63 patients had an ipsi- or bilateral tonsillectomy which revealed 12 tonsil cancers (26%). The tonsil primary was ipsilateral to positive nodes in 10 cases, contralateral in 1 case and, in 1 case, the patient had bilateral neck involvement. The analysis of the p16 status was carried out in 41/63 patients (65%). Among the 32 patients who had a p16 analysis and tonsillectomy, the rate of primary detection was 59% (10/17) for p16-postives and 0% (0/15) for p16-negatives (p < 0.001).

Conclusion

These results suggest that an extended work-up should be systematically proposed including bilateral tonsillectomy (+/- mucosectomy of the base of tongue) in SCC-CUP p16-positive patients but not in p16-negatives.

The Additional Value of Ultrafast DCE-MRI to DWI-MRI and 18F-FDG-PET to Detect Occult Primary Head and Neck Squamous Cell Carcinoma

Simple Summary

Patients with cervical lymph node metastasis from squamous cell carcinoma undergo extensive irradiation or surgery of the head and neck with higher treatment morbidity, recurrence rate and lower overall survival than patients with overt primary tumor. In order to enhance treatment efficiency and morbidity reduction, the primary tumor detection accuracy was evaluated by using Ultrafast-Dynamic Contrast-Enhancement (DCE-)MRI in addition to Diffusion-Weighted (DW-)MRI and ¹⁸F-FDG-PET/CT imaging. Ultrafast-DCE, with a temporal resolution of 4 s, enabled capturing lesions with increased neoangiogenesis or perfusion compared to normal tissue. The use of Ultra-fast DCE resulted in higher confidence for suspicious locations and high observer agreement. Ultrafast-DCE showed potential to improve detection of unknown primary tumors in addition to DWI and ¹⁸F-FDG-PET/CT in patients with cervical squamous cell carcinoma lymph node metastasis. The combined use of ultrafast-DCE, DWI and ¹⁸F-FDG-PET/CT yielded highest sensitivity.

Abstract

To evaluate diagnostic accuracy of qualitative analysis and interobserver agreement of single ultrafast-DCE, DWI or ¹⁸F-FDG-PET and the combination of modalities for the detection of unknown primary tumor (UPT) in patients presenting with cervical lymph node metastasis from squamous cell carcinoma (SCC). Between 2014–2019, patients with histologically proven cervical lymph node metastasis of UPT SCC were prospectively included and underwent DWI, ultrafast-DCE, and ¹⁸F-FDG-PET/CT. Qualitative assessment was performed by two observers per modality. Interobserver agreement was calculated using the proportion specific agreement. Diagnostic accuracy of combined use of DWI, ultrafast-DCE and ¹⁸F-FDG-PET/CT was assessed. Twenty-nine patients were included (20 males. [68%], median age 60 years). Nine (31%) primary tumors remained occult. Ultrafast-DCE added reader confidence for suspicious locations (one additional true positive (5%), 2 decisive true malignant (10%). The per-location analysis showed highest specific positive agreement for ultrafast-DCE (77.6%). The per-location rating showed highest sensitivity (95%, 95%CI = 75.1–99.9, YI = 0.814) when either one of all modalities was scored positive, and 97.4% (95%CI = 93.5–99.3, YI = 0.774) specificity when co-detected on all. The per-patient analysis showed highest sensitivity (100%) for ¹⁸F-FDG-PET/CT (YI = 0.222) and either DWI or PET (YI = 0.111). Despite highest trends, no significant differences were found. The per-patient analysis showed highest specific positive agreement when co-detected on all modalities (55.6%, 95%CI = 21.2–86.3, YI = 0.456). Ultrafast-DCE showed potential to improve detection of unknown primary tumors in addition to DWI and ¹⁸F-FDG-PET/CT in patients with cervical squamous cell carcinoma lymph node metastasis. The combined use of ultrafast-DCE, DWI and ¹⁸F-FDG-PET/CT yielded highest sensitivity.

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.

Comparative cohort study of volumetric modulated arc therapy for squamous cell cancer of unknown primary in the head and neck-Involved neck only versus mucosal irradiation

OBJECTIVES

Target volumes for irradiation remain ill-defined for squamous cell cancer of unknown primary in the head and neck (SCCUP). The aim of this study was to compare involved neck only (INO) radiotherapy (RT) with irradiating involved neck plus potential mucosal primary sites and contralateral neck (MUC) in patients diagnosed and treated with modern diagnostics and techniques.

DESIGN

This is a retrospective cohort study. Patients with a diagnosis of SCCUP with unilateral neck disease were included.

RESULTS

Thirty patients were identified. All underwent FDG PET-CT. 47% of patients had HPV-positive SCC. 20 patients received RT to INO, 10 patients to MUC, all with volumetric modulated arc therapy (VMAT). A significantly lower dose for each organ at risk was delivered in INO-treated patients, with mean dose to contralateral parotid gland 57% less. The proportion of patients with late grade 2 or worse xerostomia was higher in MUC patients. The incidence of grade 2-3 mucositis (89% vs 45%) and grade 3 or worse dysphagia (50% vs 10%) was higher in MUC patients. Median follow-up was 31 months. No mucosal primaries emerged. Progression-free survival at 2 years was 74.7% for INO patients, 70% in the MUC group. Overall survival at 2 years was 79.7% in the INO group and 70% in the MUC patients.

CONCLUSION

INO radiotherapy for patients with SCCUP of the head and neck is a safe treatment strategy resulting in clinically significant lower RT doses to OARS. Acute and late toxicities are reduced without detriment to patient survival.

Parapharyngeal metastasis from papillary thyroid microcarcinoma

Carcinoma of the thyroid gland is one of the most commonly encountered endocrine malignancies. Papillary carcinoma is the most common histological type and its pattern of metastasis are usually lymphatic. Lymphatic metastasis to parapharyngeal space is rare and have been reported, so we report the case of a 50-year-old male patient who had an occult papillary carcinoma of the thyroid presented as right lateral node of the neck and a nodal involvement of the right parapharyngeal space.

Detection and Oncologic Outcomes of Head and Neck Squamous Cell Carcinoma of Unknown Primary Origin

BACKGROUND/AIM

To assess factors that predict detection of tumors and oncologic outcomes in head and neck squamous cell carcinoma of unknown primary (SCCUP).

PATIENTS AND METHODS

This was a retrospective cohort study at a single tertiary care institution.

RESULTS

The primary site was detected at examination under anesthesia (EUA) in 92 (51.1%) patients. The primary site was detected by directed biopsies in 60 (65%), palatine tonsillectomy in 28 (30.4%), and lingual tonsillectomy in 4 patients (4.3%). Four of eight lingual tonsillectomies were positive (50%). Primary locations included: palatine tonsils (51, 28.3%), base of tongue (37, 20.6%), larynx (4, 2.2%), oral cavity (3, 1.67%) and nasopharynx (1, 0.6%). Human papillomavirus (HPV) positive status (HR=0.26, p=0.004) and treatment with chemoradiation (CRT) (HR=0.38, p=0.004) were associated with better disease free survival (DFS).

CONCLUSION

A primary site was located after aggressive investigation in approximately half of the patients. More research is warranted towards the use of lingual tonsillectomy. Predictors of favorable prognosis included HPV positive status and treatment with CRT.

TORS Base-of-Tongue Mucosectomy in Human Papilloma Virus-Negative Carcinoma of Unknown Primary

OBJECTIVE

To analyze the role of transoral robotic base-of-tongue mucosectomy in a cohort of patients with human papilloma virus negative unknown primary carcinoma.

STUDY DESIGN

Retrospective database analysis.

METHODS

A retrospective database review from 2012 to 2018 was performed at two large tertiary centers to study patients with human papilloma virus (HPV)-negative unknown primary carcinoma who underwent transoral robotic base-of-tongue mucosectomy. P16 testing was used as a surrogate for HPV status. Patients were included that had squamous cell carcinoma metastatic to the lateral neck based on fine needle aspiration or open biopsy. Preoperatively, all patients were classified as having an unknown primary based on normal clinical and flexible endoscopic exam, normal operative endoscopy, nonlocalizing imaging, and tonsillectomy. All patients underwent robotic base-of-tongue mucosectomy. The primary outcome measure was the incidence of pathologic identification of a mucosal primary.

RESULTS

Twenty-three patients with p16-negative unknown primary carcinoma were identified and studied. All patients underwent transoral robotic base-of-tongue mucosectomy. Median age was 60 years at the time of diagnosis, and 18 of 23 (78.2%) were male. Pathologic analysis of the base-of-tongue specimens showed a primary tumor in only three of 23 (13.0%) of patients.

CONCLUSION

Despite prior evidence suggesting a high rate of primary site identification in HPV-related disease, robotic base-of-tongue mucosectomy may not be indicated for HPV-negative unknown primary carcinoma based on a low likelihood of finding the primary.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:78-81, 2021.

Transoral robotic surgery: a 4-year learning experience in a single Danish Cancer Centre

Background: The main indication for transoral robotic surgery (TORS) has been the primary treatment of oropharyngeal squamous cell carcinoma (OPSCC). In the western world this is highly relevant due to the increasing incidence of human papillomavirus (HPV)-positive OPSCC. In Denmark, TORS was implemented in 2013 for use in the protocolled primary treatment of OPSCC.Aims/objectives: To perform a year-by-year comparative analysis of indications for TORS, hospitalization and complication rates to identify optimal future indications for TORS.Methods and materials: This is a retrospective single-centre case review from 2013-2017. Data were collected from patient files through electronic health care systems.Results: Since 2013, there has been a change of indications from performing benign and salvage surgery to mainly primary treatment of OPSCC and diagnostic use in patients with cancer of unknown primary (CUP). The overall complication rates have reduced considerably over time.Conclusions and significance: Lower complication rates may be explained by improved surgical experience, through better patient selection and changes in indications for TORS. Future applications of TORS will be in the management of CUP and as part of a Danish national randomized clinical trial aiming to compare long-term functional outcomes after treatment of early-stage OPSCC with TORS versus radiation treatment.

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.

Narrow band imaging in head and neck unknown primary carcinoma: A systematic review and meta-analysis

OBJECTIVE

To estimate the diagnostic performance of Narrow Band Imaging (NBI) in patients with cervical metastasis from head and neck squamous cell carcinoma of unknown primary (SCCUP) origin.

METHODS

PubMed, Embase, and Scopus databases were systematically scrutinized up to July 1, 2019, looking for studies that encompassed the NBI in the SCCUP diagnostic work up. The main inclusion criteria for eligible articles for the meta-analysis were non-evidence of primary tumor after physical examination and conventional cross-section imaging before NBI assessment and the availability of complete data on the diagnostic accuracy of NBI. A set of random-effects model meta-analyses was then performed following the Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines.

RESULTS

Five studies, conducted between January 2003 and September 2016, comprising 169 patients imaged with NBI, were included in the meta-analysis. The pooled sensitivity and specificity of NBI in patients with head and neck SCCUP was 0.83 (99% CI, 0.54-0.95) and 0.88 (99% CI, 0.55-0.97), respectively. The positive and negative likelihood ratios were 6.38 (99% CI, 1.6-25.44) and 0.06 (99% CI, 0.005-0.86). The pooled diagnostic odds ratio (DOR) was 82.15 (99% CI, 7.06-955). The overall detection rate of NBI was 0.35 (99% CI, 0.18-0.53), which allowed localization the primary tumor in 61 out of 169 patients, otherwise not detected by the usual diagnostic work-up.

CONCLUSIONS

Current available evidence suggests that NBI has a considerable diagnostic accuracy in patients affected by head and neck SCCUP. Laryngoscope, 130:1692-1700, 2020.

Current Practices and Novel Techniques in the Diagnosis and Management of Neuroendocrine Tumors of Unknown Primary

Neuroendocrine tumors (NETs) comprise a heterogeneous group of neoplasms in which tumor staging/prognosis and response to treatments depend heavily on accurate and timely identification of the anatomic primary site or NET subtype. Despite recent technological advancements and use of multiple diagnostic modalities, 10% to 14% of newly diagnosed NETs are not fully characterized based on subtype or anatomic primary site. Inability to fully characterize NETs of unknown primary may cause delays in surgical intervention and limit potential treatment options. To address this unmet need, clinical validity and utility are being demonstrated for novel approaches that improve NET subtype or anatomic primary site identification. Functional imaging using Ga-radiolabeled DOTATATE positron emission tomography/computed tomography has been shown to overcome some false-positive and resolution issues associated with octreotide scanning and computed tomography/magnetic resonance imaging. Using a genomic approach, molecular tumor classification based on differential gene expression has demonstrated high diagnostic accuracy in blinded validation studies of different NET types and subtypes. Given the widespread availability of these technologies, we propose an algorithm for the workup of NETs of unknown primary that integrates these approaches. Including these technologies in the standard workup will lead to better NET subtype identification and improved treatment optimization for patients.

Giant Spinal Intradural Metastatic Adenocarcinoma of Unknown Primary: A Rare Case Report

Giant intradural metastases of nonneurogenic origin involving multiple segments represent an extremely rare manifestation of an unknown primary. The respective literature is very scarce. We present a 45-year-old female with complaints of low back pain for 4 years, involuntary urination for 2 years, and difficulty in using both lower limbs for 1 month. Examination revealed paraparesis with hypotonia. Imaging of lumbosacral spine revealed that expansile lytic destruction of vertebral bodies and posterior elements was noted from D8 to S2 vertebra and a large-sized patchy enhancing heterogeneous intradural extramedullary lesion was noted in D8–S2 level. Decompressive laminectomy from D11 to L4 vertebra and subtotal excision of the lesion were done. There was a marked improvement in the lower limb weakness and low back pain postoperatively. Histopathology revealed metastatic adenocarcinoma. Immunohistochemistry showed epithelial membrane antigen positivity. Accordingly, the aim of the surgery is strictly palliative. The majority of patients benefit with respect to neurological deficit/pain independent of the extent of resection. Thus, decompressive surgery is recommended to increase the quality of life. The occurrence of intradural spinal metastasis is rare. Only few cases of intra dural spinal metastasis involving multiple cord segments and osteolytic bony erosions have been documented. Hence this case is being presented here for its rarity and its uniqueness.

Treatment of melanoma of unknown primary in the era of immunotherapy and targeted therapy: A Dutch population-based study

Melanoma of unknown primary (MUP) may have a different biology to melanoma of known primary, but clinical trials of novel therapies (e.g., immune checkpoint or BRAF/MEK inhibitors) have not reported the outcomes in this population. We therefore evaluated the overall survival (OS) among patients with MUP in the era of novel therapy. Data for stage III or IV MUP were extracted from a nationwide database for the period 2003–2016, with classification based on the eighth edition of the American Joint Committee on Cancer criteria. The population was divided into pre‐ (2003–2010) and post‐ (2011–2016) novel therapy eras. Also, OS in the post‐novel era was compared between patients with stage IV MUP by whether they received novel therapy. In total, 2028 of 65,110 patients (3.1%) were diagnosed with MUP. Metastatic sites were known in 1919 of 2028 patients, and most had stage IV disease (53.8%). For patients with stage III MUP, the 5‐year OS rates were 48.5% and 50.2% in the pre‐ and post‐novel eras, respectively (p = 0.948). For those with stage IV MUP, the median OS durations were unchanged in the pre‐novel era and post‐novel era when novel therapy was not used (both 4 months); however, OS improved to 11 months when novel therapy was used in the post‐novel era (p < 0.001). In conclusion, more than half of the patients with MUP are diagnosed with stage IV and the introduction of novel therapy appears to have significantly improved the OS of these patients.

What's new?

Melanoma of unknown primary (MUP) site may have a different biology to melanoma of known primary, but clinical trials of novel therapies (e.g., immune checkpoint or BRAF/MEK inhibitors) have not reported the outcomes in this population. Knowledge about outcomes could however aid clinical management of patients with MUP. In this nationwide study from 2003 to 2016, the authors show that the introduction of novel therapy has significantly improved the overall survival for patients with stage IV melanoma of unknown primary, who represented more than half of the patients diagnosed with MUP in the Netherlands.

Melanoma of unknown primary

Formally described in the 1960s, melanoma of unknown primary (MUP) is characterized by the finding of metastatic melanoma within the lymph nodes, subcutaneous tissues, and other distant sites without an evident primary lesion. The most likely hypothesis of its etiology is an immune-mediated regression of the primary after metastasis has occurred. In addition, patients with MUP appear to have equivalent or better outcomes compared with patients with known primaries of a similar stage.

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.

Detection of unknown primary tumor in patients presented with brain metastasis by F-18 fluorodeoxyglucose positron emission tomography/computed tomography

Aim:

F-18 fluorodeoxyglucose (FDG) PET/CT has several advantages in diagnosis of cancer of unknown primary with reported incremental diagnostic value. In this study, we evaluated the patients who were presented with multiple brain metastasis and unknown primary tumor.

Materials & methods:

31 patients (17 males, 14 females; mean: 56.1 ± 14.22 years old) with diagnosis of brain metastasis according to histopathology and/or MRI were included into this retrospective study.

Results:

The patients presented with hypermetabolic (n = 17; mean SUVmax: 11.6 ± 6.9) or hypometabolic brain lesions with additional different metastatic sites in 13 patients (mean SUVmax: 9.03 ± 4.02). The primary tumor was determined by FDG PET/CT in 20/26 patients (77%) (lung [n = 6], primary brain [n = 9], renal cell carcinoma [n = 2], skin [n = 1], breast [n = 1] and neuroendocrine tumor [n = 1]).

Conclusion:

New generation multislice scanners may provide higher detection ratios. The detection rate of FDG PET/CT might be higher than previously reported according to this study.

Diagnostic Value of Lingual Tonsillectomy in Unknown Primary Head and Neck Carcinoma Identification After a Negative Clinical Workup and Positron Emission Tomography-Computed Tomography

Objective

Diagnostic rates of unknown primary head and neck carcinoma (UPHNC) using lingual tonsillectomy (LT) are highly variable. This study sought to determine the diagnostic value of LT in UPHNC identification using strict inclusion criteria and definitions to produce a more accurate estimate of diagnosis rate.

Methods

In this retrospective chart review, records of patients who underwent LT for UPHNC were reviewed. Inclusion criteria included absence of suspicious findings on physical exam and positron emission tomography-computed tomography as well as negative biopsies after panendoscopy and palatine tonsillectomy. Following inclusion criteria, 16 patients were reviewed. A systematic literature review on LT for the workup of CUP was also performed.

Results

LT was performed using transoral robotic surgery (TORS), transoral laser microsurgery (TLM), or transoral microsurgery with cautery (TMC). Following LT, primary tumor was identified in 4 patients out of 16. Detection rate by technique was 1/6, 2/7, and 1/3 for TORS, TLM, and TMC respectively. Postoperative bleeding occurred in three patients (19%); however, this was not related to the LT. Following literature review, 12 studies were identified; however, only 3 had enough data to compare against. All three studies had a cohort with suspicious findings on clinical exam. A total of 34 patients had a negative workup, with no suspicious findings on clinical exam and subsequently received an LT.

Conclusion

This study suggests that LT should be considered initially in the diagnostic algorithm for UPHNC. This study can increase the patient size in this cohort by approximately 47%.

Unilateral radiotherapy treatment for p16/human papillomavirus-positive squamous cell carcinoma of unknown primary in the head and neck

OBJECTIVES/HYPOTHESIS

The outcomes of unilateral radiotherapy treatment for patients with p16/HPV-positive squamous cell carcinomas of unknown primary (SCCUP) affecting cervical lymph nodes are under-reported. Compared to radiating large volumes of the pharyngeal axis (the more common approach), this is potentially a much less toxic treatment for a good prognosis group.

STUDY DESIGN

Retrospective cohort study.

METHODS

We identified patients with SCCUP who were treated radically at our center and did not have parotid or isolated level IV or V nodal involvement. Failure-free and overall survivals were calculated using Kaplan-Meier methods.

RESULTS

From 2004 to 2012, there were 49 radically treated patients with SCCUP. Fourteen patients had bilateral neck treatment (they had bilateral nodal disease or suspected lesions in the base of tongue, though not proven with biopsy), two had surgery alone, whereas 33 had unilateral radiotherapy (after neck dissection, excisional biopsy, or definitively with concurrent chemotherapy). Of the 33 patients, 21 tested positive to p16/HPV and had median follow-up of 57 months. In this group, no isolated contralateral neck failures or putative primaries emerged. There was 1/21 (4.3%) ipsilateral neck failure, 1/21 (4.3%) concurrent contralateral neck and distant failure, and 1/21 (4.3%) patient with distant failure. The 5-year freedom from failure was 78% (95% confidence interval [CI]: 56%-100%) and overall survival was 90% (95% CI: 79%-100%).

CONCLUSIONS

With no emergence of putative primaries and no isolated contralateral neck failures, this single-institution experience in p16/HPV-positive SCCUP patients suggests that unilateral radiotherapy may be an underutilized management strategy.

LEVELS OF EVIDENCE

4 Laryngoscope, 128:2076-2083, 2018.

Optimization of radiotherapy for neck carcinoma metastasis from unknown primary sites: a meta-analysis

This meta-analysis was designed to evaluate radiotherapy (RT) options preferable for neck cancer metastases from unknown primary sites (NCUP). Relevant articles published up through September 2015 were selected from EMBASE, Cochrane, PubMed and Web of Science. Thirty-three articles were identified, and relative risks (RRs) and 95% CIs for all pre-specified endpoints were calculated. Surgery plus RT showed an advantage for 5-year overall survival (OS) (RR 0.66, 95% CI 0.52-0.83, p = 0.0004) and neck recurrence (NR) (RR = 0.74, 95% CI 0.59-0.92, p = 0.008) compared to RT alone. The RRs for NR, primary tumor emergence (PTE), and 5-year disease free survival (DFS) for bilateral neck compared to ipsilateral neck irradiation were 0.61 (95% CI 0.41-0.91, p = 0.01), 0.44(95% CI 0.26-0.77, p = 0.004), and 0.81 (95% CI 0.64-1.03, p = 0.09), respectively. Irradiation of the neck plus potential primary tumor sites (PPTS) showed a benefit for 5-year DFS (RR 0.75, 95% CI 0.61-0.92, p = 0.005), NR (RR = 0.72, 95% CI 0.56-0.92, p = 0.009), and PTE (RR = 0.23, 95% CI 0.12-0.45, p < 0.0001) compared to neck-only irradiation. Adverse events occurred more frequently with bilateral neck plus PPTS irradiation. For NCUP, surgery plus RT of the bilateral neck and PPTS was associated with greater improvement of clinical outcomes.

Implementation of a metastatic malignancy of unknown primary origin service led by a palliative physician

BACKGROUND

Cancer of unknown primary is the fourth most common cause of cancer death in the United Kingdom. National guidance in 2010 recommended the establishment of a dedicated unknown primary team to facilitate targeted investigation and symptom control. A service development project was undertaken to identify those affected by malignancy of unknown origin and institute a pathway for coordinating their care led by a palliative physician.

METHOD

In order to describe the patient population and illness trajectory and to assess the effect of the new pathway on the clinical outcomes we used a retrospective and prospective comparative case notes survey to identify the pre- and post-pathway population. This took place in secondary care. Inclusion criteria were patients with metastatic disease with no known primary; exclusion criteria were where the site of metastasis was so suggestive of a primary that it would be managed as per that disease process. 88 patients were included.

RESULTS

Mean age was 72.5 years. The mean survival time from presentation was 81.8 days. There was no difference pre or during pathway implementation in age, performance status or survival time. There was no reduction in the numbers referred for tumour directed therapy. There was a non-statistically significant reduction in the number who died in hospital during the pathway implementation.

CONCLUSIONS

This study suggests having a metastatic malignancy of unknown primary origin service led by a palliative physician does not reduce the number referred for tumour directed therapy. It also adds evidence of the poor prognosis and thus the need for early palliative care input.

Oropharynx-directed ipsilateral irradiation for p16-positive squamous cell carcinoma involving the cervical lymph nodes of unknown primary origin

BACKGROUND

The purpose of this study was to present our findings on the use of limited-field, oropharynx-directed ipsilateral irradiation for p16-positive squamous cell carcinoma of unknown primary origin.

METHODS

Between April 2011 and January 2016, 25 patients with a histological diagnosis of p16-positive squamous cell carcinoma were selectively irradiated to the ipsilateral oropharynx and cervical neck for tumors of unknown primary origin. The dose to the oropharynx ranged from 54-60 Gy (median 60 Gy) in 30-33 fractions. Concurrent cisplatin-based chemotherapy was administered to 8 patients (32%).

RESULTS

The actuarial 2-year estimates of locoregional control, progression-free survival, and overall survival were 91%, 87%, and 92%, respectively. One patient failed in the contralateral neck. There was no grade 3 + toxicity in either the acute or late setting.

CONCLUSION

Oropharynx-directed, ipsilateral radiation results in disease control that compares favorably with historical controls treated by comprehensive mucosal and bilateral neck radiation.

Management of head and neck primary unknown squamous cell carcinoma using combined positron emission tomography-computed tomography and transoral laser microsurgery

OBJECTIVES/HYPOTHESIS

The unknown primary of the neck is commonly encountered by the head and neck surgeon. Despite the exhaustive diagnostic tools employed in traditional detection protocols, many unknown primaries are not found, and the patient is subjected to wide-field radiation and chemotherapy during treatment. Localizing the primary tumor has demonstrated therapeutic benefits, improved quality of life, and overall survival. The authors' objective was to determine the efficacy of a new management protocol for unknown primaries of the head and neck.

STUDY DESIGN

Prospective cohort study.

METHODS

Our technique involved a preoperative positron emission tomography-computed tomography (PET-CT) followed by a planned transoral laser microsurgery (TLM) approach. Efficacy was assessed based on survival statistics, disease control, detection rates, the proportion of patients not receiving adjuvant therapy, and the proportion of PET-CT scans helpful for detection of the primary cancer.

RESULTS

The occult primary was located in 25 of the 27 patients (93%), with the majority found in the palatine tonsil (52%). Both overall survival and disease-specific survival was 80% at 36 months. Local control was achieved in 100% of patients. After surgery, 37.0% (n = 10) received adjuvant radiation alone and 33.3% (n = 9) of patients went on to receive adjuvant chemoradiation. On imaging, 72% (n = 18) of PET-CT scans correctly localized the primary tumor.

CONCLUSIONS

Occult head and neck primaries present a diagnostic challenge that is not adequately overcome using traditional detection protocols. The current study presents our unique protocol at Dalhousie University, which demonstrates the efficacy of the PET-CT TLM protocol from both a detection and therapeutic perspective.

LEVEL OF EVIDENCE

4. Laryngoscope, 128:2307-2311, 2018.