• This ESMO–EURACAN Clinical Practice Guideline provides key recommendations for managing salivary gland cancer. • The guideline covers clinical and pathological diagnosis, staging and risk assessment, treatment and follow-up. • Treatment algorithms for parotid, submandibular, sublingual and minor salivary gland cancer are provided. • The author group encompasses a multidisciplinary group of experts from different institutions and countries in Europe. • Recommendations are based on available scientific data and the authors’ collective expert opinion.

• Keywords
• ESMO–EURACAN Clinical Practice Guideline, diagnosis, follow-up, salivary gland cancer, treatment,
• MeSH
• Adult MeSH
• Medical Oncology MeSH
• Humans MeSH
• Salivary Gland Neoplasms * diagnosis   therapy   MeSH
• Follow-Up Studies MeSH
• Check Tag
• Adult MeSH
• Humans MeSH
• Publication type
• Journal Article MeSH
• Practice Guideline MeSH
• Geographicals
• Europe MeSH

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.

• Keywords
• Cribriform adenocarcinoma of minor salivary glands, Pathology, Polymorphous adenocarcinoma, Polymorphous low-grade adenocarcinoma, Prognosis, Salivary glands, Therapy,
• MeSH
• Adenocarcinoma pathology   surgery   therapy   MeSH
• Humans MeSH
• Salivary Glands, Minor * MeSH
• Salivary Gland Neoplasms pathology   therapy   MeSH
• Prognosis MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Review MeSH

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".

• Keywords
• FISH, Immunohistochemistry, Larynx, RT-PCR, Unclassified malignancies,
• MeSH
• Humans MeSH
• Laryngeal Neoplasms classification   diagnosis   pathology   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Review MeSH

Salivary gland hybrid tumour, first described in 1996, is a very rare neoplasm for which exact morphological criteria have not been universally agreed upon. In contrast, the concept of high-grade transformation (HGT) in salivary neoplasms has been widely accepted during the last decade, and the number of reported cases is rapidly increasing. A review of the literature revealed 38 cases of hybrid tumour reported in 22 publications. During approximately the same time period, well over 100 cases of HGT in salivary neoplasms have been reported. There are important histological similarities between hybrid tumours and salivary tumours with HGT. In the latter, containing one tumour component of low-grade malignancy and the other of high grade, the two tumour components are not entirely separated and appear to originate in the same area. Virtually, all cases reported as hybrid tumour had no clear lines of demarcation between the two tumour types. We are inclined to suggest that most of the 38 cases of hybrid tumours described in the literature would today better be called tumour with HGT rather than hybrid tumour. The relative proportion of the two components may vary, and the high-grade component is sometimes very small, which emphasises the importance of very generous sampling of the surgical specimen. The molecular genetic mechanisms responsible for HGT, including what used to be called hybrid tumour, remain largely unknown. Abnormalities of a few genes (including p53, C-MYC, cyclin D1, HER-2/neu) have been documented. As insufficient data exist on gene abnormalities in these lesions, conclusions as to whether or not they have a common origin and which mechanisms are involved in transformation cannot be drawn. Due to the small number of cases reported, many of which lack follow-up details; indicators of prognosis of hybrid tumours are not available, but their behaviour seems to be similar to that of tumours with HGT, i.e. an accelerated aggressive course. HGT of salivary gland neoplasms greatly influences macroscopic and microscopic evaluation of the specimen but also, given the high incidence of metastases and morbidity, carries significant treatment implications.

• Keywords
• Dedifferentiation, High-grade transformation, Hybrid tumour, Salivary gland neoplasms, Salivary glands,
• MeSH
• Adult MeSH
• Genes, myc genetics   MeSH
• Middle Aged MeSH
• Humans MeSH
• Cell Transformation, Neoplastic pathology   MeSH
• Salivary Gland Neoplasms diagnosis   pathology   MeSH
• Prognosis MeSH
• Neoplasms, Second Primary diagnosis   pathology   MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Neoplasm Grading MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH