Composite poorly differentiated mucoepidermoid carcinoma of
A 71-year-old man was referred by his General practitioner to a district general hospital head and neck clinic with breathlessness and haemoptysis. On initial presentation the patient did not describe any changes in voice, dysphagia, odynophagia, weight loss with a prior smoking history. His past medical history revealed that 6 years previously, he had been fully investigated for a left vocal cord palsy of presumed idiopathic aetiology and had undergone medialisation of injection thyroplasty.

Computed tomography (CT) imaging depicted a paratracheal mass within the left trachea-oesophageal groove. Several enlarged lymph nodes were found in the antero-superior mediastinum and left paratracheal space as well as individual lymph nodes in the retrocaval, pretracheal and subcarinal regions. Ultrasound demonstrated several colloid nodules in the thyroid with abnormal heterogenous areas and focal areas of calcification. A positron emission tomography computed tomography (PET/CT) scan further identified lung and bony metastatic deposits.

At microlaryngoscopy under general anaesthesia a subglottic mass was biopsied. The initial biopsy results showed stratified squamous epithelium that was hyperplastic and spongiotic with scattered and highly atypical cells with nuclear polymorphism and abundant eosinophilic cytoplasm. Immunohistochemistry of these tissue samples showed positivity for Cytokeratin7 (CK7) and Periodic Acid Schiff Alcian (PAS-alc) blue and negativity for Cytokeratin20 (CK20) and Thyroid transcription factor 1 (TTF1). Due to lack of evidence of thyroid markers on these tissues, an initial diagnosis of ‘mucoid’ tumour of the trachea was made. Based on this evidence, the tumour was staged at T4N2M1.

Clinical management of the patient involved microdebridement of the tumour under general anaesthesia and a palliative dose of radiotherapy (20 Gray in five doses) which failed to improve the patient’s airway obstruction. The patient underwent a surgical tracheostomy at which multiple further pathological samples were taken. These showed evidence of papillary thyroid carcinoma with a follicular growth pattern which was shown to blend imperceptibly with another component of tumour wherein the cells are present in irregular discohesive infiltrating growth pattern. The nuclei of these cells were found to be hyperchromatic with moderate cytoplasm, whilst several of the cells showed intracytoplasmic lumen and eosinophilic inclusions.

Immunohistochemistry showed positivity for TTF1 and thyroglobulin in the papillary component of the carcinoma whilst the poorly differentiated area showed negativity for TTF1 and weak positivity for thyroglobulin. This led to the diagnosis of a follicular variant of papillary thyroid carcinoma with composite MEC of the thyroid. Due to the extensive nature of the disease, the patient was managed with palliative intent and died 2 months later.

Read more:
p●●●●i k●●●●●a and 1 others like this1 share