Adenosquamous carcinoma of the head and neck: report of 20 cases and review of the literature

Laryngeal Cancer in the Modern Era: Evolving Trends in Diagnosis, Treatment, and Survival Outcomes

Background/Objectives: Laryngeal cancer (LC), predominantly squamous cell carcinoma (SCC), represents a considerable health burden worldwide. Tumour subsite heterogeneity (supraglottic, glottic, subglottic) influences clinical behavior and outcomes. This review synthesizes current knowledge on epidemiology, risk factors, diagnostics, histological variants, biomarkers, treatment modalities, and survival. Results: This narrative review synthesizes current literature on the epidemiology, risk factors, diagnosis, histological variants, biomarkers, and prognosis of LC. The review highlights the critical influence of tumour sites (supraglottic, glottic, subglottic) on metastatic patterns and survival. Key risk factors of LC include tobacco and alcohol use, human papillomavirus (HPV) infection, and occupational exposures. The diagnostic process encompasses clinical examination, endoscopy, biopsy, and imaging. Several biomarkers that aid in diagnosis, treatment plan determination, and prognosis prediction have been established. These biomarkers include long noncoding RNAs, cell cycle regulators, apoptosis regulators, oncogenes, tumour suppressor genes, growth factor pathway components, angiogenic factors, structural proteins, sex hormone receptors, and immunological markers. Current treatment modalities range from organ-preserving surgery and radiotherapy to combined chemoradiotherapy and total laryngectomy. Finally, survival data are presented and stratified by stage and subsite. Conclusions: The review underscores the need for a multidisciplinary approach to LC management, integrating clinical, pathological, and molecular information to optimize patient outcomes.

Prognostic implications across histological subtypes of head and neck squamous cell carcinoma: An update

BACKGROUND

Head and neck squamous cell carcinoma (HNSCC) is one of the most common malignancies worldwide, arising from the mucosal epithelium of the oral cavity, oropharynx, hypopharynx, nasopharynx, larynx, and sinuses. In addition to the conventional morphologic pattern characterized by the degree of cellular atypia and squamous differentiation, HNSCC is classified into eight histopathologic subtypes: basaloid, spindle cell, adenosquamous, cuniculatum, verrucous, lymphoepithelial, papillary, and acantholytic.

METHODS

This review provides a comprehensive review of the literature on the prognostic implications of the histological subtypes of HNSCC.

RESULTS

Although there is extensive literature on HNSCC, few studies specifically focus on the treatment and prognosis of its histopathologic subtypes. Among these subtypes, verrucous squamous cell carcinoma and carcinoma cuniculatum generally have a favorable prognosis, while others, such as basaloid and spindle cell squamous cell carcinoma, tend to follow a more aggressive clinical course.

CONCLUSION

In this review, we delve into the histopathological subtypes of HNSCC and explore their clinicopathological, molecular, and prognostic findings. Further molecular investigations aimed at identifying targeted therapies for these subtypes are necessary. Moreover, it is crucial to recognize the emerging histopathological variants documented in the literature, considering the ongoing limitations in prognostic assessment.

Sinonasal Adenosquamous Carcinoma - Morphology and Genetic Drivers Including Low- and High-Risk Human Papillomavirus mRNA, DEK::AFF2 Fusion, and MAML2 Rearrangement

BACKGROUND

Sinonasal adenosquamous carcinoma is rare, and there are almost no studies detailing morphology or characterizing their genetic driver events. Further, many authors have termed sinonasal tumors with combined squamous carcinoma and glands as mucoepidermoid carcinoma but none have analyzed for the presence of MAML2 rearrangement.

METHODS

Cases from 2014 to 2020 were collected and diagnosed using World Health Organization criteria. They were tested for p16 expression by immunohistochemistry (70% cut-off), DEK::AFF2 fusion by fluorescence in situ hybridization (FISH) and AFF2 immunohistochemistry, MAML2 rearrangement by FISH, and low- and high-risk HPV by RNA ISH and reverse transcription PCR, respectively. Detailed morphology and clinical features were reviewed.

RESULTS

There were 7 male (64%) and 4 female (36%) patients with a median age of 69 years, most Caucasian (10 of 11 or 91%). Most had tobacco exposure (8/11, 73%) and most presented with epistaxis, a visible nasal mass, and/or facial pain. Several had a precursor papillomas (3 of 11, 27%). The squamous component had variable keratinization, 5 of 11 (46%) of which would be described as keratinizing, 3 non-keratinizing, and 2 with mixed features. All had gland formation, by definition, and 2 of 11 (18%) had ciliated tumor cells. None of the 11 cases had MAML2 rearrangement and one had DEK::AFF2 fusion with associated positive nuclear AFF2 protein immunostaining. Most were p16 positive (7 of 11, 64%) and all 7 of these were hrHPV positive either by RNA ISH or RT-PCR. Two of the p16-negative tumors were positive for lrHPV by RNA ISH. Treatment included surgery alone (4 of 11, 36%), surgery with adjuvant radiation (5 of 11, 45%), and surgery with radiation and chemotherapy (2 of 11, 18%). Four of 11 patients (36%) suffered disease recurrence, two requiring re-operation and who were disease free at last follow-up, one receiving additional chemotherapy and who was alive with disease. The other elected to undergo palliative therapy and died of disease.

CONCLUSION

Sinonasal adenosquamous carcinoma is a somewhat heterogeneous tumor not infrequently arising ex papilloma and having various drivers including high- and low-risk HPV and rarely DEK::AFF2 fusion. The prognosis appears favorable when proper treatment is possible.

Adenosquamous Carcinoma with the Acantholytic Feature in the Oral Cavity: A Case Report and Comprehensive Literature Review

Adenosquamous carcinoma (ASC) is an aggressive subtype of squamous cell carcinoma (SCC). Due to its poor prognosis, a precise pathological diagnosis of ASC is essential but challenging because its pathological criteria are still unclear. Here, we present a rare case of oral ASC accompanied by acantholytic features. The tumor was raised in the mandibular gingiva and recurred locally approximately 13 months after the initial surgery with cervical lymph node metastasis. Pathological specimens of the primary lesion showed acantholysis in a large area of the SCC. Mucous cells, the characteristic finding indicating glandular differentiation, were imperceptible in the initial surgical specimen but increased in the locally recurrent and metastatic lymph node specimens. In a comprehensive literature review of oral ASC cases, the present case was the only case of ASC with acantholytic features. We reconfirmed that ASC has poor prognoses, such as low 5-year overall survival and disease-free survival, high locoregional recurrence, and high distant metastasis rates. A precise diagnosis of ASC is required for estimating prognosis and undergoing close follow-up, even if the adenocarcinomatous component is limited to a small area in the lesion.

Aggressive squamous cell carcinoma of the cranium of a dog

BACKGROUND

The authors report a case of keratinized squamous cell carcinoma (SCC) in a 14-year-old dog with extensive cranial bone invasion. To our knowledge, this is the first description of such a case of cranial keratinized SCC with aggressive generalized osteolysis described in a dog.

CASE PRESENTATION

The 14-year-old dog was referred for radiological examination with suspicion of head trauma with clinical signs of head deformation, exophthalmos and nasal discharge. The skull radiographs showed a large osteolytic defect of the frontal bone and parietal bone in the region of the external sagittal crest. Findings from the skull CT scan included generalized osteolysis in the region of parietal bone, frontal bones, maxilla on the right side and the nasal bone including the dorsal nasal concha. In the area of bone loss, new soft tissue formation with multifocal foci of mineralization was visible. The ultrasound examination revealed hypoechogenic changes with hyperechoic foci consistent with mineralization and poor vascularization. The brain and ocular structures were without visible changes. Fine needle aspiration cytology (FNAC) was performed, and squamous cell carcinoma was suspected. After 3 months, the re-presented to the clinic. The dog became progressively listless, his appetite was decreased, and he became acutely blind. Follow-up skull CT scan revealed significant osteolysis, which affected a significant aspect of the cranium. All bone defects had been replaced by new 3.5 cm-thick soft tissue formations with multifocal small 1-2 mm areas of mineralization. There was no evidence of metastasis. Histological examination confirmed the suspicion of squamous cell carcinoma.

CONCLUSIONS

This paper is the first report of cranial SCC in a dog causing extensive bone osteolysis. The lesions in this dog originated from the frontal and parietal bones including frontal sinuses. There are variants of tumors that arise from squamous epithelium or resemble SCC in the skull. These examples include adenosquamous carcinoma and proliferating trichilemmal tumours. In addition, there is possible malignant transformation caused by papilloma viruses. In the veterinary literature, there is only one similar description of adenosquamous carcinoma in a cat with similar clinical manifestations. It is justified to suspect a process of neoplastic epithelial origin in all cases of aggressive and extensive skull bone lysis. This issue should be subject to further investigation.

Clinico-pathological peculiarities of human papilloma virus driven head and neck squamous cell carcinoma: A comprehensive update

AIMS

The current article provides a detailed account of the current understanding of molecular and clinico-pathological aspects of Human papilloma virus (HPV) driven head and neck squamous cell carcinoma (HNSCC).

MATERIALS AND METHODS

The literature review included most of the landmark trials and clinical studies related to the HPV driven HNSCC.

KEY FINDINGS

HPV positive HNSCC differ distinctly from HPV negative tobacco-related HNSCC, especially in oropharyngeal region. Therefore, the American joint committee on cancer`s latest manual for classification and staging of cancer suggests a separate staging system for HPV positive oropharyngeal cancers. Despite the younger patients being affected and the high propensity for cervical metastasis, the HPV positive oropharyngeal cancers respond much better to the treatment. The association with wild type TP53 and low EGFR expression confers the favorable prognosis in HPV driven HNSCC. Since the association is not universal, we suggest checking for p53 and EGFR expression status before considering de-intensification of therapy. In addition, the presence of matted lymph nodes and five or more nodes could mean relatively poorer prognosis, and are not suitable for de-intensification of therapy. The same is also true probably with higher T stage and co-existing tobacco use. The methods for the detection of p16, HPV DNA, HPV E6/E7 mRNA, anti-E6/E7 antibodies, in tissue, in serum and in saliva of patients, along with their clinical implications are also discussed.

SIGNIFICANCE

This article provides latest developments on the HPV driven HNSCC. 'Diagnosis of transcriptionally active HPV infection,' 'Modalities for surveillance,' 'Implication of de-escalation of therapy' are some of the critical issues that could serve the medical, the research as well as the patient communities.

Rare variants of head and neck squamous cell carcinoma -differential immunohistochemical profiles

We aimed to immunohistochemically characterize the pattern of expression of epithelial markers in rare head and neck squamous cell carcinoma (HNSCC) variants: carcinoma cuniculatum (CC) and adenosquamous carcinoma (ASC). We also present an additional variant of HNSCC with concomitant basaloid and squamous components that has overlapping morphological features with odontogenic and non-odontogenic tumors, which we termed basalo-squamous carcinoma (BSC). The selected markers included CK5/6, p40, CK19, BerEP4, p16 and SOX10. All tumors were CK5/6 and p40 positive. CK19 and BerEP4 were positive in BSC and focally in ASC but negative in CC. p16 was positive in 3 (60%) of the CCs, focally positive in ASC and negative in BSC. SOX10 was negative in all three variants. Our results highlight the plasticity of the lining epithelium revealing differential profiles of immuno-expression of the selected molecular markers, possibly reflecting their diverse histopathogenesis.

Adenosquamous carcinoma development as a recurrence of squamous cell carcinoma in the oral floor: A case report

RATIONALE

Oral adenosquamous carcinoma (ASC) is rare and its origins are controversial. We here present a patient with oral ASC that developed after surgery for oral squamous cell carcinoma (SCC).

PATIENT CONCERNS

A 70-year-old man with SCC on the oral floor underwent surgical resection. However, the enlarged ulcer presented on the oral floor 9 month after surgery.

DIAGNOSES

The biopsy of the ulcer revealed a SCC. Imaging examinations detected enhancement of a large lesion expanded to the tongue, but no evidence of regional lymph node or distant metastasis was shown. Based on these results, local recurrence of the cancer was diagnosed (cT4aN0M0).

INTERVENTIONS

The surgery for the recurrent tumor was performed.

OUTCOMES

The pathological examination of the surgical specimen indicated recurrent tumor was ASC. Thus, histopathological and immunohistochemical analyses of both the initial SCC and the subsequent ASC were performed in an attempt to explore the origin of the ASC. As the results, pathological review of both tumors suggested the subsequent ASC was developed from the tumor cells with adenoid phenotype in the initial SCC.

LESSONS

This report suggests that the oral ASC was origin from the oral SCC, which can contribute to new knowledge for pathogenesis of oral cancer.

Data Set for the Reporting of Oral Cavity Carcinomas: Explanations and Recommendations of the Guidelines From the International Collaboration of Cancer Reporting

The International Collaboration on Cancer Reporting is a nonprofit organization whose goal is to develop evidence-based, internationally agreed-upon standardized data sets for each cancer site for use throughout the world. Providing global standardization of pathology tumor classification, staging, and other reporting elements will lead to the objective of improved patient management and enhanced epidemiologic research. Carcinomas of the oral cavity continue to represent a significant oncologic management burden, especially as changes in alcohol and tobacco use on a global scale contribute to tumor development. Separation of oral cavity carcinomas from oropharyngeal tumors is also important, as management and outcome are quite different when human papillomavirus association is taken into consideration. Topics such as tumor thickness versus depth of invasion, pattern of invasive front, extent and size of perineural invasion, and margin assessment all contribute to accurate classification and staging of tumors. This review focuses on the data set developed for Carcinomas of the Oral Cavity Histopathology Reporting Guide, with discussion of the key elements developed for inclusion.

Adenosquamous carcinoma, a rare and unknown tumor

Introduction: Adenosquamous carcinoma (ASC) of the head and neck is a rare malignant tumor, with one hundred cases diagnosed so far in the literature. Observation: A 66 years old female patient had a ASC of the right posterior floor of the mouth with a classification T1N0M0. Treatment consisted of surgical management and active surveillance. Discussion: Through this case report, we present this type of tumor and we discuss the main differential diagnosis from a clinical and histological point of view. Conclusion: This entity was described for the first time in 1968 by Gerughty. The CAS is defined by the World Health Organization as “a tumor of the upper respiratory tract, with two distinct squamous and glandular components.” The CAS is considered as an aggressive tumor with a redoubtable prognosis should not be ignored.

Adenosquamous Carcinoma in the Midline Dorsum of the Tongue: A Rare Case Report

Adenosquamous carcinoma (ASC) is a rare malignant tumor of the oral and maxillofacial region that displays histologic features of both adenocarcinoma and squamous cell carcinoma. ASC in the midline dorsum of the tongue is exceedingly rare. We report the case of a 48-year-old man who presented with a painless mass in the midline dorsum of the tongue. Although the case was diagnosed as adenocarcinoma by biopsy, a final diagnosis of ASC was established after surgery. Ten months after the patient's initial visit, no recurrence or metastasis has been noted. ASC in the middle dorsum of the tongue is exceedingly rare, and no examples have been reported hitherto.

Adenosquamous Carcinoma of the Tongue

A 51-year-old white female presented with a painful ulcer of the left ventrolateral tongue. An incisional biopsy confirmed a diagnosis of adenosquamous carcinoma. The adenosquamous carcinoma is an uncommon malignant tumor with histopathological features of a squamous carcinoma and an adenocarcinoma. A definitive diagnosis requires histopathological examination of a deep biopsy involving the submucosal tissue. This malignant tumor shows aggressive behavior with early invasive growth and a poor prognosis. The histopathological findings and differential diagnosis of a case of adenosquamous carcinoma of the tongue are discussed.

Laryngeal Dysplasia, Squamous Cell Carcinoma, and Variants

Squamous cell carcinoma (SCC) is a malignant epithelial tumor showing evidence of squamous differentiation. It is the most common malignancy of the larynx, with several variants (verrucous, exophytic or papillary, spindle-cell, basaloid, acantholytic, adenosquamous) recognized, with well-established precursor lesions. Dysplasia is now separated into only low-grade and high-grade categories. Each SCC variant has unique cytomorphologic features and histologic differential diagnoses that are important to consider, as management and outcomes are different.

Importance of tumor extent in adenosquamous carcinoma of the head and neck: a retrospective cohort study

OBJECTIVE

The aim of this study was to determine the correlates of survival for patients diagnosed with adenosquamous carcinoma (ASC) of the head and neck.

STUDY DESIGN

Patients diagnosed with ASC of the head and neck between 1973 and 2012 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. Kaplan-Meier and Cox proportional hazard regression analyses were conducted to investigate the prognostic factors and treatment modalities that determine overall survival (OS) and disease-specific survival (DSS).

RESULTS

In the analysis, of the 235 patients diagnosed with adenosquamous of the head and neck, 66.8% were male and 33.2% were female with a median age at diagnosis of 64 years. Kaplan-Meier analysis determined 5-year survival rates of 30% for OS and 50% for DSS. Univariate and multivariate analyses found that age at diagnosis, tumor size, tumor extent of disease, surgical resection, and radiation therapy were independent predictors of OS and DSS.

CONCLUSIONS

This study, to our knowledge, is the largest study, to date, determining the correlates of survival for ASC of the head and neck. Older age at diagnosis, larger tumor size, and further extent of disease were correlated with decreased survival. Surgical resection improves survival in patients with localized or regional disease, whereas radiation therapy confers survival benefit in patients with distant extent.

Oral Adenosquamous Carcinoma Mimicking a Pyogenic Granuloma: a Challenging Diagnosis

Adenosquamous carcinoma is an aggressive variant of squamous cell carcinoma. This report describes a case of adenosquamous carcinoma with clinical features of a benign lesion and discusses the differential diagnoses, especially regarding histopathological and immunohistochemical analyses. A 45-year-old male was referred to our outpatient clinic complaining about a rapid-growing enlargement in hard palate. Clinical examination revealed an erythematous and pedunculated nodule with lobulated non-ulcerated surface. Excisional biopsy was performed following clinical diagnosis of pyogenic granuloma. Histologically, the specimen consisted of areas characterizing both well-differentiated squamous cell carcinoma and true adenocarcinoma. After a broad list of immunohistochemical markers was evaluated (AE1/AE3, CEA, CK5, CK7, CK8/18, p53, p63 and Ki67), the diagnosis of adenosquamous carcinoma was rendered and the patient referred to complementary surgery. Adenosquamous carcinoma represents a challenge in diagnostic routine due to its rarity, diverse range of clinical presentations and histological features. Furthermore, classical clinical benign features may be present in malignant lesions; hence the submission of every surgical specimen to histological analysis is mandatory to provide the patient the adequate treatment.

Update from the 4th Edition of the World Health Organization Classification of Head and Neck Tumours: What is New in the 2017 WHO Blue Book for Tumours of the Hypopharynx, Larynx, Trachea and Parapharyngeal Space

Chapter 3 "Tumours of the hypopharynx, larynx, trachea, and parapharyngeal space" of the World Health Organization (WHO) Blue Book 2017 "Classification of Head and Neck Tumours" shows a shortened list of entities, especially due to reducing the number of benign and malignant soft tissue tumours, malignant melanoma and some others, which are transferred to more frequently affected regions of the head and neck. The basic concept of the new edition is to assimilate all advances concerning the discussed tumours in a shorter framework, appropriate for daily work. The main emphasis is on the most frequent lesions and tumors originating from the covering squamous epithelium. Laryngeal and hypopharyngeal conventional squamous cell carcinoma (CSCC), its variants and precursor lesions, occupy a major part of the chapter. New data on etiopathogenesis, with the focus on human papillomavirus (HPV) infection, are discussed in relation to the entities of the squamous epithelium. Although only a small fraction of these lesions are HPV-related, further studies are required for evaluation of the potential prognostic and therapeutic benefit of mRNA HPV determination. In contrast to earlier data, laryngeal and hypopharyngeal verrucous SCC, spindle cell SCC and basaloid SCC are not anymore considered as HPV-related tumours. New data on the pathogenesis of spindle cell SCC exhibiting divergent differentiation by epithelial-mesenchymal transition, are also briefly discussed. The most important innovation is brought by the section on precursor lesions, in which a unified two-tier classification, consisting of low- and high-grade dysplasia, is introduced. The proposed two-tier system can also be transformed into a three-tier classification for treatment purposes, with a distinction between carcinoma in situ and high-grade dysplasia. The reviewed morphological criteria of the proposed system are based on the amended Ljubljana classification. The section on laryngeal neuroendocrine carcinomas (NEC) represents a considerable improvement in terminology and classification. NEC are divided into well-, moderate- and poorly-differentiated neuroendocrine carcinoma. The latter is additionally divided into small cell NEC and large cell NEC (LCNEC). It is of extreme importance that LCNEC, which was associated in the WHO 2005 edition with atypical carcinoid/moderately differentiated neuroendocrine carcinoma, grade II, has now been transferred into the group of poorly differentiated NEC, grade III, displaying a specific morphology and poorer prognosis.

Oral adenosquamous carcinoma: Report of a rare entity with a special insight on its histochemistry

Adenosquamous carcinoma (ASC) of the head and neck (H and N) is an aggressive variant of squamous cell carcinoma (SCC). They are described as SCC subtype with high infiltrative capacity and also presents with dual histomorphology, having both squamous and glandular cell components. ASC of the H and N region is considered as a controversial tumor, as it is similar to salivary gland mucoepidermoid carcinoma. It has been described in a variety of body sites, including uterine cervix, lung and pancreas. ASC rarely develops in the upper aerodigestive tract, particularly in the oral cavity. The affected sites in oral cavity include palate, tonsillar pillar areas and floor of the mouth. To the best of our knowledge in the literature, only 17 cases of ASC in the floor of the mouth have been reported. Hereby, we report an additional case of ASC occurring in the floor of the mouth in a 70-year-old male patient.

Adenosquamous carcinoma of the tongue: clinicopathologic study and review of the literature

Adenosquamous carcinoma (ASC) of the tongue is an uncommon malignant oral neoplasm with mixed glandular and squamous differentiation and a propensity for aggressive clinical behavior. Here, we report a rare case of ASC of the lateral border of the tongue in a 65-year-old Japanese man. The patient was treated by radical operation and remained well for 6 months before developing metastasis of the hilar and pretracheal lymph nodes. Subsequently, the patient was treated with combined chemotherapy (nedaplatin plus docetaxel and S-1 for two cycles, intravenously) and radiotherapy. Radiation therapy of metastatic lymph nodes was performed at a total dose of 60 Gy and was delivered in 2 Gy fractions 5 days/week. The patient is currently tumor free and is being followed up carefully. This article describes a rare case of ASC of the tongue and its conventional histologic, immunohistochemical, and electron microscopic findings, together with a review of the literature. The findings provide important information to better understand the possible clinical and therapeutic approaches for this uncommon tumor of the tongue.

Adenosquamous Carcinoma of the Head and Neck: A Case-Control Study with Conventional Squamous Cell Carcinoma

Adenosquamous carcinoma (AdSC) is considered a rare variant of squamous cell carcinoma (SCC) which is considered to be more clinically aggressive. Data is very limited with very little case matched data on outcomes in the literature. It is also unknown whether the quantity of the adenocarcinoma component affects outcomes. A retrospective case-control study with 23 cases of AdSC and 1137 SCC controls was conducted. Cases were matched by anatomic subsite, treatment, and, for oropharynx, by p16 status. The following variables were adjusted for in the analysis: T classification (T1/T2 vs. T3/T4), N classification (N0-N2a vs. N2b-N3), age, and smoking. The adenocarcinoma component was quantified by the number of high power fields containing glands as low, moderate, or high. AdSCs had a significantly greater risk of disease recurrence but largely, the differences were not statistically significant. The quantity of adenocarcinoma did not correlate with disease recurrence or survival. This case-control study on AdSC shows modestly more clinically aggressive behavior than conventional SCC, even while controlling for p16 status for oropharyngeal cases. Further, it suggests the current definition of AdSC, with no minimum requirement for gland formation, is clinically accurate.

A Nation-Wide Cancer Registry-Based Study of Adenosquamous Carcinoma in Taiwan

BACKGROUND

Adenosquamous carcinoma (ASC) is a rare disease involving various organs, yet there are no large-scale population-based comparative studies on ASC among different organs.

METHODS

The incidence and overall survival of ASC among various organs in cases diagnosed in Taiwan from January 1, 2003 to December 31, 2010 were calculated and compared using data from the Taiwan Cancer Registry (TCR). The various organs were classified and divided into three different systems: the female reproductive, respiratory, and alimentary systems. Survival analysis were also compared among 30,850 patients diagnosed as ASC, adenocarcinoma (AC) or squamous cell carcinoma (SCC) in organs with frequent ASC.

RESULTS

During the study period, a total of 576 ASC cases were diagnosed in Taiwan. The most common primary system was respiratory (73.8%), followed by alimentary (16.2%) and female reproductive (10%). The overall survival were significantly higher for cases involving the female reproductive system, followed by the respiratory and alimentary systems (P = 0.016). The median overall survival were worse in males than females for cases involving the respiratory system (22.4 vs. 31.8 months, P = 0.044). Multivariate analysis showed that age ≧ 65, more advanced T and N categories were independent unfavorable prognostic factors of overall survival in ASC. ASC histology is an independent unfavorable prognostic factor compared with AC and SCC.

CONCLUSIONS

ASC at an old age and more advanced T and N categories were found to be associated with a poor prognosis.

The Present and Future Opportunities of the Rare Cancer Network: An International Consortium for Advancement of Oncologic Care

To date, the Rare Cancer Network (RCN) has initiated more than 90 studies and 54 peer-reviewed publications were produced as a result. The Second International Symposium of the Rare Cancer Network recently took place in Istanbul, Turkey on April 17-18, 2015, and update was given on multiple currently ongoing projects, while also giving room for new proposals which will shape the direction of future studies for the group. This companion issue of the RCN Proceedings summarized the findings of this meeting, while also serving as a call for fresh projects and papers which will continue to energize the group and advance the oncologic science. A brief introduction to the principles, history, and vision of the RCN was also included. To review, the academic year of 2014-15 marked an enormous success for the international members of the RCN, with the generation of 8 fully published papers and more than 12 newly proposed topics. By the collective efforts of all RCN members, in the future, we look forward to the upcoming opportunities in continuing to advance the standard of chemo- and radiotherapeutic oncologic care for selected rare tumor topics. The studies of these rare cancers often do not allow the design and execution of prospectively enrolled trials; however, these uncommon malignancies do impact the humankind and add to its suffering globally in significant ways.

IMAGING DIAGNOSIS: COMPUTED TOMOGRAPHIC FINDINGS IN A CASE OF ADENOSQUAMOUS CARCINOMA OF THE HEAD AND NECK IN A CAT

A 15-year-old female spayed domestic long-haired cat was referred for trismus, hypersalivation, and bilateral ocular discharge. On examination, the cat showed pain on palpation of the left zygomatic arch, palpable crepitus of the frontal region, and limited retropulsion of both globes. A contrast-enhanced sinonasal computed tomographic study was performed, showing facial distortion and extensive osteolysis of the skull, extending beyond the confines of the sinonasal and paranasal cavities. Additionally, soft tissue and fluid accumulation were observed in the nasal cavities and paranasal sinuses. Postmortem biopsy samples acquired from the calvarium yielded a histologic diagnosis of sinonasal adenosquamous carcinoma, a rare and particularly aggressive neoplasm previously only reported in the esophagus of one cat.

History of the rare cancer network and past research

Approximately, twenty years ago, the Rare Cancer Network (RCN) was formed in Lausanne, Switzerland, to support the study of rare malignancies. The RCN has grown over the years and now includes 130 investigators from twenty-four nations on six continents. The network held its first international symposium in Nice, France, on March 21-22, 2014. The proceedings of that meeting are presented in two companion papers. This manuscript reviews the history of the growth of the RCN and contains the abstracts of fourteen oral presentations made at the meeting of prior RCN studies. From 1993 to 2014, 74 RCN studies have been initiated, of which 54 were completed, 10 are in progress or under analysis, and 9 were stopped due to poor accrual. Forty-four peer reviewed publications have been written on behalf of the RCN.

Adenosquamous carcinoma of hypopharynx with intestinal-phenotype

Adenosquamous carcinomas of the head and neck (ADSCs) are rare locally aggressive malignancies characterized by the presence of two distinctive components, a squamous cell carcinoma and an adenocarcinoma. The immunophenotype of the glandular component of ADSCs has only been rarely studied but has been reported as being positive for keratin 7 (CK7) and carcinoembryonic antigen (CEA) and negative for keratin 20 (CK20). Herein, we report a case of an ADSCs of the hypopharynx composed of a superficial squamous cell carcinoma and an adenocarcinoma with an intestinal phenotype. The patient was a 62 year-old male with a T2 N0 M0 squamous cell carcinoma (SCC) of uvula and palate and a T1 N0 M0 of right hypopharynx. The ADSCs of the hypopharynx was composed of a minimally invasive SCC and an adenocarcinoma with tubulo-glandular and cribriform architecture. The neoplastic glands were positive for CK7, CK20, CDX2, CEA and Villin. The patient underwent radiotherapy to both tumors and remains well with no evidence of recurrent disease 19 months after treatment. To the best of our knowledge, this is the first report of an ADSCs of the head and neck with an intestinal phenotype in its glandular component.

Primary adenosquamous carcinoma of the esophagus

AIM: To investigate the clinical characteristics, diagnosis, treatment, and prognosis of primary adenosquamous carcinoma (ASC) of the esophagus.

METHODS: A total of 4015 patients with esophageal carcinoma underwent surgical resection between January 1995 and June 2012 at the Cancer Hospital of Shantou University Medical College. In 37 cases, the histological diagnosis was primary ASC. Clinical data were retrospectively analyzed from these 37 patients, who underwent transthoracic esophagectomy with lymphadenectomy. The χ² or Fisher’s exact test was used to compare the clinicopathological features between patients with ASC and those with squamous cell carcinoma (SCC). The Kaplan-Meier and Log-Rank methods were used to estimate and compare survival rates. A Cox proportional hazard regression model was used to identify independent prognostic factors.

RESULTS: Primary esophageal ASC accounted for 0.92% of all primary esophageal carcinoma cases (37/4015). The clinical manifestations were identical to those of other types of esophageal cancer. All of the 24 patients who underwent preoperative endoscopic biopsy were misdiagnosed with SCC. The median survival time (MST) was 21.0 mo (95%CI: 12.6-29.4), and the 1-, 3-, and 5-year overall survival rates were 67.5%, 29.4%, and 22.9%, respectively. In multivariate analysis, only adjuvant radiotherapy (HR = 0.317, 95%CI: 0.114-0.885, P = 0.028) was found to be an independent prognostic factor. The MST for ASC patients was significantly lower than that for SCC patients [21.0 mo (95%CI: 12.6-29.4) vs 46.0 mo (95%CI: 40.8-51.2), P = 0.001]. In subgroup analyses, the MST for ASC patients was similar to that for poorly differentiated SCC patients.

CONCLUSION: Primary esophageal ASC is a rare disease that is prone to be misdiagnosed by endoscopic biopsy. The prognosis is poorer than esophageal SCC but similar to that for poorly differentiated SCC patients.