Data Set for the Reporting of Nodal Excisions and Neck Dissection Specimens for Head and Neck Tumors: Explanations and Recommendations of the Guidelines From the International Collaboration on Cancer Reporting

Standardized, synoptic pathologic reporting for tumors greatly improves communication among clinicians, patients, and researchers, supporting prognostication and comparison about patient outcomes across institutions and countries. The International Collaboration on Cancer Reporting is a nonprofit organization whose mission is to develop evidence-based, universally available surgical pathology reporting data sets. Within the head and neck region, lymph node excisions and neck dissections are frequently performed as part of the management of head and neck cancers arising from the mucosal sites (sinonasal tract, nasopharynx, oropharynx, hypopharynx, oral cavity, and larynx) along with bone tumors, skin cancers, melanomas, and other tumor categories. The type of specimen, exact location (lymph node level), laterality, and orientation (by suture or diagram) are essential to accurate classification. There are significant staging differences for each anatomic site within the head and neck when lymph node sampling is considered, most importantly related to human papillomavirus–associated oropharyngeal carcinomas and mucosal melanomas. Number, size, and site of affected lymph nodes, including guidelines on determining the size of tumor deposits and the presence of extranodal extension and soft tissue metastasis, are presented in the context of prognostication. This review elaborates on each of the elements included in the data set for Nodal Excisions and Neck Dissection Specimens for Head & Neck Tumours.

Structural biology of intraepithelial neuroendocrine cells in the larynx: Literature review

Current knowledge of laryngeal neuroendocrine cells in man and other vertebrates is reviewed. Particular attention is paid to differences in the distribution of neuroendocrine cells between squamous and respiratory laryngeal mucosa, foetal versus post-natal spatial arrangements, relation to the laryngeal cavity and nerve fibres, and immunoreactivities of these cells. Methodological deficiencies and gaps in knowledge are outlined. Comparisons with neuroendocrine cells in lung and gut are drawn, caution with regard to existing histogenetic models of laryngeal neuroendocrine neoplasia is advised and lines of future research are suggested.

Surgical margins in head and neck cancer: Intra- and postoperative considerations

OBJECTIVE

To provide a perspective on the significance of recent reports for optimizing cancer free surgical margins that have challenged standard practices.

METHODS

We conducted a review of the recent literature (2012-2018) using the keywords surgical margin analysis, frozen and paraffin section techniques, head and neck cancer, spectroscopy and molecular markers.

RESULTS

Of significance are the reports indicating superiority of tumor specimen directed sampling of margins compared to patient directed (tumor bed) sampling for frozen section control of oral cancers. With reference to optimal distance between tumor and the surgical margin, recent reports recommended cutoffs less than 5mm. Employment of new technologies such as light spectroscopy and molecular analysis of tissues, provide opportunities for a "real time" assessment of surgical margins.

CONCLUSIONS

The commonly practiced method of patient directed margin sampling involving previous studies raises concern over conclusions made regarding the efficacy of frozen section margin control. The recent studies that challenge the optimal distance for clear surgical margins are retrospective and address patient cohorts with inherently confounding factors. The use of novel ancillary techniques require further refinements, clinical trial validation, and justification based on the additional resources.

Polymorphous adenocarcinoma of the salivary glands: reappraisal and update

Although relatively rare, polymorphous adenocarcinoma (PAC) is likely the second most common malignancy of the minor salivary glands (MiSG). The diagnosis is mainly based on an incisional biopsy. The optimal treatment comprises wide surgical excision, often with adjuvant radiotherapy. In general, PAC has a good prognosis. Previously, PAC was referred to as polymorphous low-grade adenocarcinoma (PLGA), but the new WHO classification of salivary gland tumours has also included under the PAC subheading, the so-called cribriform adenocarcinoma of minor salivary glands (CAMSG). This approach raised controversy, predominantly because of possible differences in clinical behaviour. For example, PLGA (PAC, classical variant) only rarely metastasizes, whereas CAMSG  often shows metastases to the neck lymph nodes. Given the controversy, this review reappraises the definition, epidemiology, clinical presentation, diagnostic work-up, genetics, treatment modalities, and prognosis of PAC of the salivary glands with a particular focus on contrasting differences with CAMSG.

Role of ancillary techniques in profiling unclassified laryngeal malignancies

Laryngeal biopsies, contrary to biopsies from many other sites of the body, very often contain minute amounts of tumour tissue that may consist of morphologically undifferentiated tumour only. In haematoxylin- and eosin-stained sections, there may be no indicative features of what specific tumour entity that is present. In the larynx, particularly small round cell neoplasms, primary or metastatic, often cause a diagnostic dilemma and where an incorrect diagnosis can induce substantial clinical consequences for the patient (e.g., primary neuroendocrine carcinomas vs metastatic variants, certain sarcomas). If sufficient/representative material has been obtained, the application of immunohistochemistry and/or molecular techniques should in virtually every case reveal the true nature of the malignancy. In cases with sparse amount of material, and therefore a limited number of sections to be cut, a careful and thoughtful stepwise approach is necessary to ascertain a reliable diagnosis, or at least guide the clinician to the most likely diagnoses. With today's advanced and widely available technology with an abundance of markers to discriminate different tumours, the use of the term "undifferentiated" should be largely unnecessary. In the exceptional, and indeed exceedingly rare cases, when a classification is not possible, even after repeat biopsy, we suggest that the laryngeal neoplasm is better termed "unclassified malignant neoplasm" rather than "undifferentiated malignant neoplasm".

Molecular markers in well-differentiated thyroid cancer

PURPOSE

Thyroid nodules are of common occurrence in the general population. About a fourth of these nodules are indeterminate on aspiration cytology placing many a patient at risk of unwanted surgery. The purpose of this review is to discuss various molecular markers described to date and place their role in proper perspective. This review covers the fundamental role of the signaling pathways and genetic changes involved in thyroid carcinogenesis. The current literature on the prognostic significance of these markers is also described.

METHODS

PubMed was used to search relevant articles. The key terms "thyroid nodules", "thyroid cancer papillary", "carcinoma papillary follicular", "carcinoma papillary", "adenocarcinoma follicular" were searched in MeSH, and "molecular markers", "molecular testing", mutation, BRAF, RAS, RET/PTC, PAX 8, miRNA, NIFTP in title and abstract fields. Multiple combinations were done and a group of experts in the subject from the International Head and Neck Scientific Group extracted the relevant articles and formulated the review.

RESULTS

There has been considerable progress in the understanding of thyroid carcinogenesis and the emergence of numerous molecular markers in the recent years with potential to be used in the diagnostic algorithm of these nodules. However, their precise role in routine clinical practice continues to be a contentious issue. Majority of the studies in this context are retrospective and impact of these mutations is not independent of other prognostic factors making the interpretation difficult.

CONCLUSION

The prevalence of these mutations in thyroid nodule is high and it is a continuously evolving field. Clinicians should stay informed as recommendation on the use of these markers is expected to evolve.

How Phenotype Guides Management of the Most Common Malignant Salivary Neoplasms of the Larynx?

Salivary gland carcinomas of the larynx are uncommon. Adenoid cystic carcinoma is the most prevalent type of salivary gland carcinoma in this region, although other histologies such as mucoepidermoid carcinoma and adenocarcinomas have been reported. These tumors may present with advanced-stage due to nonspecific symptoms and their relatively slow-growing nature. The index of suspicion for a non-squamous cell carcinoma entity should be high when a submucosal mass is present. An accurate diagnosis is mandatory due to the impact each biologic entity has on treatment and outcome. Data concerning treatment and outcome are scarce, but primary surgery with utmost focus on free surgical margins is the treatment of choice. The role of adjuvant radiotherapy has not been well defined, although there is an agreement that it should be considered in advanced-stage or high-grade disease. This review considers only the most common malignant salivary neoplasms of the larynx with a focus on clinical management of these tumors.

How phenotype guides management of non-conventional squamous cell carcinomas of the larynx?

Although the majority of laryngeal malignancies are the conventional squamous cell carcinomas (SCC), a wide variety of malignant epithelial tumors can affect the larynx. Current treatment guidelines are designed to guide clinicians in management of conventional laryngeal SCC. Less is known about the biological behavior and responsiveness to therapy and overall outcomes of other malignant epithelial lesions. Because a spectrum of disease biology is represented by these rare phenotypes, an understanding of the basic biology can help direct management to optimize clinical outcome in this group of patients. This review provides a critical analysis of literature relating to the diagnosis, management, and outcome of patients with non-conventional squamous malignant epithelial neoplasms of the larynx. Particular attention is paid to features which are at variance with the conventional SCC and how these impact on management of these rare tumors.

Nasal juvenile angiofibroma: Current perspectives with emphasis on management

Juvenile angiofibroma is an uncommon, benign, locally aggressive vascular tumor. It is found almost exclusively in young men. Common presenting symptoms include nasal obstruction and epistaxis. More advanced tumors may present with facial swelling and visual or neurological disturbances. The evaluation of patients with juvenile angiofibroma relies on diagnostic imaging. Preoperative biopsy is not recommended. The mainstay of treatment is resection combined with preoperative embolization. Endoscopic surgery is the approach of choice in early stages, whereas, in advanced stages, open or endoscopic approaches are feasible in expert hands. Postoperative radiotherapy (RT) or stereotactic radiosurgery seem valuable in long-term control of juvenile angiofibroma, particularly those that extend to anatomically critical areas unsuitable for complete resection. Chemotherapy and hormone therapy are ineffective. The purpose of the present review was to update current aspects of knowledge related to this rare and challenging disease. © 2017 Wiley Periodicals, Inc. Head Neck 39: 1033-1045, 2017.

Incidental findings of thyroid tissue in cervical lymph nodes: old controversy not yet resolved?

The clinical significance of papillary or follicular thyroid tissue incidentally discovered in cervical lymph nodes during pathological assessment of neck dissections for non-thyroid cancers of the upper aero-digestive tract is critically reviewed. Special emphasis is given to controversies over normal-looking, nodal, thyroid follicles. Arguments for and against the benign nature of these follicles are considered together with processes that could be involved in their formation. The admittedly limited evidence suggests that benign, thyroid follicular inclusions rarely occur in cervical lymph nodes. Histological criteria that could be helpful in recognizing the inclusions, which include assessing their extent in conjunction with the size of the node, are discussed. Finally, an algorithm based on collaboration between specialists, correlating histological findings with imaging and loco-regional control of the upper aero-digestive tract cancer, is suggested for the management of patients with incidentally discovered, nodal thyroid tissue.

A Non-epithelial Pseudosarcomatous Mural Nodule in a Mucinous Cystic Neoplasm of the Pancreas

A mucinous cystic neoplasm of indeterminate malignant potential was found to have a well-circumscribed, 3.1 cm pseudosarcomatous mural nodule, similar to those previously described in the ovary. The nodule contained reactive giant cells and intermediate to large-sized tumor cells with bizarre mitotic figures and nuclear atypia. The tumor cells were found to be of non-epithelial origin, based on multiple negative stains for cytokeratins and ultrastructural demonstration of osteoclastic and osteoblastic differentiation and absent desmosomes. This case report is the only description of a pseudosarcomatous mural nodule in a mucinous cystic neoplasm with non-epithelial origins.

Functional Histology of Salivary Gland Pleomorphic Adenoma: An Appraisal

The complex microstructure of salivary gland pleomorphic adenoma is examined in relation to function. Events related to secretion of macromolecules and absorption, responses to the altered microenvironment and controversies concerning epithelial-mesenchymal transition versus modified myoepithelial differentiation are explored. Their effects on tumor cell phenotypes and arrangements are emphasized. Heterotopic differentiation and attempts at organogenesis are also considered. The approach allows interpreting microstructure independently of histogenetic perceptions, envisaging the tumor cells as a continuum, endorsing luminal structures as the principal components, and defining pleomorphic adenoma as a benign epithelial tumour characterized by variable epithelial-mesenchymal transition, secretion/differentiation and metaplasia.

Neuroendocrine neoplasms of the sinonasal region

Neuroendocrine neoplasms of the sinonasal region, which are relatively uncommon but clinically very important, are reviewed here in the light of current knowledge. Using a definition for neuroendocrine based on phenotypic, histologic, immunohistochemical, and electron microscopic features rather than histogenetic criteria, sinonasal neuroendocrine carcinomas are examined with a particular emphasis on the small-cell and large-cell subtypes. This is followed by revisiting olfactory neuroblastoma because it is also a tumor that shows a neuroendocrine phenotype. Kadish clinical and Hyams histologic grading systems as prognosticators of olfactory neuroblastoma are also considered in detail. Finally, controversies regarding sinonasal undifferentiated carcinoma as a neuroendocrine tumor are discussed and a possible relationship with high-grade olfactory neuroblastoma is explored. Genetic events and current management of these tumors are also outlined. © 2015 Wiley Periodicals, Inc. Head Neck 38: E2259-E2266, 2016.

Update on primary head and neck mucosal melanoma

Primary mucosal melanomas (PMMs) of the head and neck are uncommon malignancies that arise mainly in the nasal cavity and paranasal sinuses, followed by the oral cavity. The mainstay of treatment is radical surgical resection followed by adjuvant radiotherapy in selected patients with high-risk features. Multimodality therapy has not been well studied and is not standardized. Adjuvant radiotherapy seems to improve locoregional control but does not improve overall survival (OS). Elective neck dissection is advocated in patients with oral PMM. Systemic therapy should be considered only for patients with metastatic or unresectable locoregional disease. Despite improvements in the field of surgery, radiotherapy, and systemic therapy, patients with PMM still face a very unfavorable prognosis (5-year disease-free survival [DFS] <20%) with high rates of locoregional recurrence and distant metastasis. The present review aims to summarize the current state of knowledge on the molecular biology, pathological diagnosis, and management of this disease.

Adenoid cystic carcinoma of the head and neck--An update

This article provides an update on the current understanding of adenoid cystic carcinoma of the head and neck, including a review of its epidemiology, clinical behavior, pathology, molecular biology, diagnostic workup, treatment and prognosis. Adenoid cystic carcinoma is an uncommon salivary gland tumor that may arise in a wide variety of anatomical sites in the head and neck, often with an advanced stage at diagnosis. The clinical course is characterized by very late recurrences; consequently, clinical follow-up should extend at least >15 years. The optimal treatment is generally considered to be surgery with postoperative radiotherapy to optimize local disease control. Much effort has been invested into understanding the tumor's molecular biological processes, aiming to identify patients at high risk of recurrence, in hopes that they could benefit from other, still unproven treatment modalities such as chemotherapy or biological therapy.

Rhabdomyoblastic Differentiation in Head and Neck Malignancies Other Than Rhabdomyosarcoma

Rhabdomyosarcoma is a relatively common soft tissue sarcoma that frequently affects children and adolescents and may involve the head and neck. Rhabdomyosarcoma is defined by skeletal muscle differentiation which can be suggested by routine histology and confirmed by immunohistochemistry for the skeletal muscle-specific markers myogenin or myoD1. At the same time, it must be remembered that when it comes to head and neck malignancies, skeletal muscle differentiation is not limited to rhabdomyosarcoma. A lack of awareness of this phenomenon could lead to misdiagnosis and, subsequently, inappropriate therapeutic interventions. This review focuses on malignant neoplasms of the head and neck other than rhabdomyosarcoma that may exhibit rhabdomyoblastic differentiation, with an emphasis on strategies to resolve the diagnostic dilemmas these tumors may present. Axiomatically, no primary central nervous system tumors will be discussed.

Frequent chromosomal aberrations and candidate genes in head and neck squamous cell carcinoma

The knowledge of the biology of head and neck squamous cell carcinoma (HNSCC) has had relatively little impact on the improvement in oncologic outcome up to date. However, the identification of oncogenes and tumor suppressor genes (TSGs) involved in cancer progression contributes to the understanding of the molecular pathways involved in oncogenesis and could contribute to individual risk assessment and provide tools for improvement of treatment and targets for therapy based on the alterations in these pathways. The aim of this article is to review the chromosomal aberrations commonly found in HNSCC, to identify the genes in these chromosomal regions suggested to act as (candidate) oncogenes or TSGs, and to discuss the molecular mechanisms modulating their expression.

Advances in diagnostic modalities to detect occult lymph node metastases in head and neck squamous cell carcinoma

Regional metastasis is a prominent feature of head and neck squamous cell carcinoma (HNSCC) and is an important prognostic factor. The currently available imaging techniques for assessment of the neck have limitations in accuracy; thus, elective neck dissection has remained the usual choice of management of the clinically N0 neck (cN0) for tumors with significant (≥20%) incidence of occult regional metastasis. As a consequence, the majority of patients without regional metastasis will undergo unnecessary treatment. The purpose of this review was to discuss new developments in techniques that potentially improve the accuracy of the assessment of the neck in patients with HNSCC. Although imaging has improved in the last decades, a limitation common to all imaging techniques is a lack of sensitivity for small tumor deposits. Therefore, complementary to improvements in imaging techniques, developments in more invasive diagnostic procedures, such as sentinel node biopsy (SNB) will add to the accuracy of diagnostic algorithms for the staging of the neck.

The pathology milestones and the next accreditation system

CONTEXT

In the late 1990s, the Accreditation Council for Graduate Medical Education developed the Outcomes Project and the 6 general competencies with the intent to improve the outcome of graduate medical education in the United States. The competencies were used as the basis for developing learning goals and objectives and tools to evaluate residents' performance. By the mid-2000s the stakeholders in resident education and the general public felt that the Outcomes Project had fallen short of expectations.

OBJECTIVE

To develop a new evaluation method to track trainee progress throughout residency using benchmarks called milestones. A change in leadership at the Accreditation Council for Graduate Medical Education brought a new vision for the accreditation of training programs and a radically different approach to the evaluation of residents.

DATA SOURCES

The Pathology Milestones Working Group reviewed examples of developing milestones in other specialties, the literature, and the Accreditation Council for Graduate Medical Education program requirements for pathology to develop pathology milestones. The pathology milestones are a set of objective descriptors for measuring progress in the development of competency in patient care, procedural skill sets, medical knowledge, practice-based learning and improvement, interpersonal and communication skills, professionalism, and systems-based practice.

CONCLUSIONS

The milestones provide a national standard for evaluation that will be used for the assessment of all residents in Accreditation Council for Graduate Medical Education-accredited pathology training programs.

Desmoid tumors of the head and neck: a therapeutic challenge

Desmoid tumor, or aggressive fibromatosis, is a rare, histologically benign, fibroblastic lesion that infrequently presents in the head and neck. Desmoid tumors often grow locally, invasively, and may, in rare instances, be fatal secondary to invasion into critical structures, such as airway or major vessels. The most common treatment is surgery, but desmoid tumors are characteristically associated with a high local recurrence rate after resection. Although the margin status seems to be of importance, operations that avoid function loss and esthetic disfigurement should be the primary goal. The efficacy of postoperative radiotherapy is controversial. Its potential benefit should be carefully balanced against possible radiation-induced adverse effects. Alternative treatment modalities, such as primary radiotherapy and medical treatment or a wait-and-see policy, may be preferable to mutilating surgery. Considering all the aforementioned, it seems obvious that desmoid tumors of the head and neck present a therapeutic challenge and require an individualized approach.

Unusual thyroid tumors: a review of pathologic and molecular diagnosis

The most common thyroid neoplasms are either follicular derived (papillary, follicular and Hürthle cell lesions) or C-cell derived (medullary carcinoma). The diagnosis of these tumors can usually be made at the histologic level, with immunohistochemical stains necessary in some circumstances. Specific molecular mutations have been described that can be diagnostically useful or explain, in part, their pathogenesis, including the well-known Ret/PTC and PPARgamma-PAX8 translocations, point mutations in the Ret, Ras and BRAF genes, and loss of heterozygosity of multiple different tumor suppressor genes. Some unusual tumors of the thyroid gland are more difficult to diagnose. In examining these lesions, the pathologist may use the hematoxylin and eosin-stained morphology, coupled with an analysis of the immunohistochemical staining profiles and possibly analysis of the underlying molecular mutational patterns. These less common thyroid tumors include tall cell and cribriform-morular variants of papillary carcinoma, hyalinizing trabecular tumor, mucoepidermoid and sclerosing mucoepidermoid carcinoma with eosinophilia, poorly differentiated (insular) carcinoma, and undifferentiated (anaplastic) carcinoma. The diagnostic features of these rare tumors, including the histology, immunohistochemical expression profiles and the known molecular mutational profiles of each, are reviewed.

The sinonasal tract: another potential "hot spot" for carcinomas with transcriptionally-active human papillomavirus

While high risk human papillomavirus (HPV) is well established as causative and clinically important for squamous cell carcinoma (SCC) of the oropharynx, its role in non-oropharyngeal head and neck SCC is much less clearly elucidated. In the sinonasal region, in particular, although it is a relatively uncommon site for SCC, as many as 20 % of SCC harbor transcriptionally-active high risk HPV. These tumors almost always have a nonkeratinizing morphology and may have a better prognosis. In addition, specific variants of SCC as well as other rare carcinoma types, when arising in the sinonasal tract, can harbor transcriptionally-active HPV. This article reviews the current literature on HPV in sinonasal carcinomas, attempts to more clearly demonstrate what tumors have it and how this relates to possible precursor lesions like inverted papilloma, and discusses the possible clinical ramifications of the presence of the virus.

Chondrosarcomas of the head and neck

Chondrosarcoma represents approximately 11% of all primary malignant bone tumors. It is the second most common sarcoma arising in bone after osteosarcoma. Chondrosarcomas of the head and neck are rare and may involve the sinonasal tract, jaws, larynx or skull base. Depending on the anatomical location, the tumor can produce a variety of symptoms. Computed tomography and magnetic resonance imaging are the preferred imaging modalities. The histology of conventional chondrosarcoma is relatively straightforward; major challenges are the distinction between grade I chondrosarcomas and chondromas, and the differential diagnosis with chondroblastic osteosarcoma and chondroid chordoma. Surgery alone or followed by adjuvant radiotherapy is the treatment of choice. Radiotherapy alone has also been reported to be effective and can be considered if mutilating radical surgery is the only curative alternative. The 5-year survival for chondrosarcoma reaches 80%; distant metastases and/or local recurrences significantly worsen prognosis. The present review aims to summarize the current state of information about the biology, diagnosis and management of these rare tumors.

Molecular diagnostic alterations in squamous cell carcinoma of the head and neck and potential diagnostic applications

Head and neck squamous cell carcinoma (HNSCC) is a common malignancy that continues to be difficult to treat and cure. In many organ systems and tumor types, there have been significant advances in the understanding of the molecular basis for tumorigenesis, disease progression and genetic implications for therapeutics. Although tumorigenesis pathways and the molecular etiologies of HNSCC have been extensively studied, there are still very few diagnostic clinical applications used in practice today. This review discusses current clinically applicable molecular markers, including viral detection of Epstein-Barr virus and human papillomavirus, and molecular targets that are used in diagnosis and management of HNSCC. The common oncogenes EGFR, RAS, CCND1, BRAF, and PIK3CA and tumor suppressor genes p53, CDKN2A and NOTCH are discussed for their associations with HNSCC. Discussion of markers with potential future applications is also included, with a focus on molecular alterations associated with targeted therapy resistance.

The Molecular Pathology of Salivary Gland Tumors with Translocations

Presented here are the salivary gland tumors now recognized to have significant and highly prevalent translocations. These include both common and uncommon malignancies: mucoepidermoid carcinoma, adenoid cystic carcinoma, mammary analog secretory carcinoma, and clear cell carcinoma. These mutations have potential diagnostic applications, particularly in difficult and challenging variant morphologies are unusually challenging differential diagnoses. Practical applications of the molecular pathology of these tumors is discussed. The mutational assessment may also prove to have therapeutic importance, as targeted therapies may be generated for these tumors in the future.

Staining for acid-fast bacilli in surgical pathology: practice patterns and variations

Analysis of acid-fast bacilli stains on sputum smears for the diagnosis of tuberculosis has a long history, but quality control for acid-fast bacilli in histologic sections is not as well established. In tissues, necrotizing granulomas are closely linked to positive cultures for mycobacteria. However, the practices of pathologists examining acid-fast bacilli in surgical specimens are not well described in the literature. This study characterizes practice patterns related to the histologic interpretation of acid-fast bacilli stains. A survey invitation was sent to 1299 pathologists including members of the Pulmonary Pathology Society and randomly selected fellows of the College of American Pathologists. Twenty-one questions inquired about demographics, ordering and interpreting acid-fast bacilli stains, reporting, and correlation. Of the 392 responses (30.2% response rate), 363 respondents review acid-fast bacilli stains on histologic sections. Approximately half of respondents practice in an academic setting, with the other half in community practice. Most respondents examine the entire acid-fast bacilli slide with the ×40 objective; approximately half confirm the organisms under oil immersion at ×100. There was considerable variation in when an acid-fast bacilli stain is ordered, as well as possible additional workup for negative cases, reporting of results, correlation with clinical and culture findings, and training. Many respondents reported never having been taught a general approach to acid-fast bacilli interpretation. There is substantial variation in practice patterns involving all aspects of ordering, histologic examination, and reporting of acid-fast bacilli stains. Future efforts to standardize the interpretation of acid-fast bacilli stains can potentially improve the diagnosis of mycobacterial disease.

An update on molecular diagnostics of squamous and salivary gland tumors of the head and neck

CONTEXT

Molecular testing in anatomic pathology is becoming standardized and can contribute valuable diagnostic, therapeutic, and prognostic information for the clinical management of patients. In head and neck pathology, recent advances in molecular testing have provided important targets in several different diagnostic areas, with particular emerging clinical applications in squamous and salivary gland pathology. In squamous mucosal-derived lesions, human papilloma virus has emerged as an important pathogenic etiology in a subset of oropharyngeal squamous cell carcinomas. Within the category of salivary gland tumors, 3 tumors have recently been recognized that contain oncogenic translocations.

OBJECTIVE

To describe the current state of information about the molecular alterations in squamous lesions and in salivary gland tumors of the head and neck.

DATA SOURCES

Published literature on squamous and salivary gland tumors of the head and neck.

CONCLUSIONS

The different approaches to identification of viral-associated tumors include assays using polymerase chain reaction, in situ hybridization, and immunohistochemistry. Most mucoepidermoid carcinomas harbor MECT1-MAML2 gene rearrangement. The MYB-NFIB translocations have recently been identified in adenoid cystic carcinomas. Finally, a newly described tumor of salivary gland, mammary analogue secretory carcinoma, harbors the ETV6-NTRK3 translocation. Although these translocations are just emerging as diagnostic targets, future roles may evolve as potential therapeutic targets.

Clear cell carcinoma and clear cell odontogenic carcinoma: a comparative clinicopathologic and immunohistochemical study

Clear cell carcinoma or hyalinizing clear cell carcinoma (CCC) and clear cell odontogenic carcinoma (CCOC) are rare, low-grade and typically indolent malignancies that can be diagnostically challenging. In this study the clinicopathologic, histologic, and immunohistochemical features of 17 CCCs and 12 CCOCs are examined. The differential diagnosis of clear cell malignancies in the head and neck is discussed. The relationship of CCCs and CCOCs to other clear cell tumors on the basis of their immunohistochemical staining patterns is postulated.

KRAS gene mutation in colorectal cancer is correlated with increased proliferation and spontaneous apoptosis

KRAS mutation occurs in 30% to 50% of colorectal cancers (CRCs) and has been suggested to be associated with proliferation and decreased apoptosis. In this study, we analyzed KRAS in 198 CRCs and compared the clinicopathologic variables between KRAS-mutated and wild-type CRCs. Also, a subset of 90 and 66 CRCs from this cohort underwent microsatellite instability testing and histomorphologic evaluation, and the frequency of microsatellite instability-high (MSI-H) and histomorphologic variables were compared between KRAS-mutated and wild-type CRCs. Clinicopathologic features (age, sex, and tumor site, depth, size, grade, and metastasis) were not different between KRAS-mutated and wild-type CRCs. Compared with wild-type KRAS CRCs, KRAS-mutated CRCs had a lower frequency of MSI-H (15% vs 42%; P = .015), a higher chance of having brisk mitosis (77% vs 43%, P = .022) and apoptosis (77% vs 28%; P = .00012), and a greater mean of mitotic figures (P = .0002) and apoptotic cells (P = .0008). KRAS mutation was associated with higher tumor cell turnover.

Ewing's family of tumors of the sinonasal tract and maxillary bone

The Ewing's family of tumors (EFT) are malignant neoplasms affecting children and young adults. Most cases arise in the long bones or the pelvis. Primary EFT of head and neck is uncommon and primary sinonasal EFT is even rarer. Previous studies have not focused on the sinonasal region specifically, and the published literature on sinonasal EFT consists of sporadic case reports. Fourteen cases of sinonasal EFT were available and had H&Es for review and immunohistochemical stains for CD99, S100, keratins, synaptophysin and desmin. FISH or RT-PCR was performed for EWSR1 abnormalities on 8 cases. The 14 identified patients included 5 males and 9 females, ranging from 7-70 years of age (mean 32.4 years). Tumors involved nasal cavity (5), sinuses (5) or both (4). Five patients had dural, orbital or brain involvement. The majority involved bone radiologically and/or microscopically. All cases were composed of small cells with variable cytoplasmic clearing. Focal or prominent nesting was noted in most cases. All cases were positive for CD99. Keratins (AE1/3 and/or CAM5.2), S100 and synaptophysin were positive in 4, 3 and 5 cases, respectively. All cases were negative for desmin. The 8 cases tested by FISH or RT-PCR were positive for EWSR1 abnormalities. Follow-up in 8 patients ranged from 1-168 months (average 11.3 m) showing 1 death due to metastatic disease, 1 death due to local disease, 1 patient alive with metastases and 5 patients disease-free at last follow-up. Interestingly, however, an analysis of the literature suggests a better prognosis for sinonasal EFT than EFT overall.

Assessment of immunohistochemistry for p16INK4 and high-risk HPV DNA by in situ hybridization in esophageal squamous cell carcinoma

The role of high-risk human papillomavirus (HPV) in the pathogenesis of esophageal squamous cell carcinoma (ESCC) remains unclear. p16(INK4) is used as a surrogate marker to detect HPV-related tumors but has had discrepant results in ESCC. In this study, 32 cases of ESCC were examined to determine the relationship between p16(INK4) expression and high-risk HPV. All the tumors were stained by immunohistochemistry for p16(INK4). Tumors having p16(INK4) nuclear and/or nuclear and cytoplasmic expression were considered positive. Tumors positive for p16(INK4) expression were tested for high-risk HPV by in situ hybridization (ISH). In all, 20 cases of ESCC (63%) showed only cytoplasmic staining for p16(INK4), and 11 cases (34%) showed both cytoplasmic and nuclear staining for p16(INK4); 4 cases (13%) showed no staining for p16(INK4). None of the p16(INK4) -positive cases were positive for high-risk HPV by ISH. These results indicate that p16(INK4) expression in ESCC does not correlate with the presence of high-risk HPV DNA by ISH. High-risk HPV does not seem to play a major role in the carcinogenesis of ESCC in low-risk areas.