94 When the gut affects the heart

A 59-year-old man came to our attention with progressive shortness of breath associated with lower limb oedema. He complained also of recurrent malar flushing, diarrhea and weight loss (14 kg in the last 8 months). At physical examination, a holosystolic murmur best heard over the fourth left sternal border, intensified upon inspiration, and a palpable tender liver with irregular surface were noted.

Transthoracic and transesophageal echocardiogram revealed dilated right chambers. The tricuspid annulus was dilated and the leaflets thickened, shortened and retracted with restricted mobility and incomplete coaptation, leading to severe tricuspid regurgitation (Panels A-B). Moderate pulmonary regurgitation was also detected (Panel C). Cardiac MR confirmed the morphology of the tricuspid valve (Panels D-E, arrows) and the severity of the tricuspid regurgitation (regurgitant fraction 66%). The pulmonary valve leaflets were also thickened and fixed (Panel F, arrow), with moderate pulmonary regurgitation (regurgitant fraction 21%).

With the suspicion of carcinoid syndrome, 5-hydroxyindoleacetic acid (5-HITT) was tested by 24-hour urine sample and a value of 929.5 µmol/24h was found (n.v. 10.5-47.1).

Whole body 18-F DOPA PET was performed. Axial views and reconstructed images revealed a short segment of mural thickening (2.4 cm and 1.1 cm) in the jejunum with a moderate/high uptake (Panels G, arrow). Adjacent to this lesion, a mesenteric spiculated mass (4.0 x 2.8 cm) with moderate uptake was visible (Panels H, arrow). Multiple enhancing nodules with high uptake were present in the liver (Panel I).

One of the liver nodules was biopsied. The biopsy revealed extensive infiltration by well differentiated neuroendocrine tumor (Panel J, blue arrow). The tumor cells were arranged in nests and were composed of cells with round to oval nuclei and eosinophilic cytoplasm (Panel K). The neuroendocrine nature of the tumor was confirmed by strong diffuse positivity with synaptophysin (Panel L), chromogranin and CD 56. Ki-67 showed a proliferative index of less than 3%. The tumor morphology, combined with the immunohistochemical features, was in keeping with a well differentiated neuroendocrine tumor.

Carcinoid heart disease is a rare cause of primary tricuspid and pulmonary valve disease leading to significant morbidity and mortality caused by right heart failure. The characteristic pathological findings are endocardial plaques of fibrous tissue that may involve the tricuspid valve and, rarely, the pulmonary valve. The fibrous tissue in the plaques results in distortion of the valves leading to either stenosis, regurgitation, or both.

Abstract 94 Figure.

Sclerosing Mucoepidermoid Carcinoma of the Submandibular Gland Presenting as Chronic Sialadenitis: A Case Report and Review of Literature

Sclerosing mucoepidermoid carcinoma of the salivary gland (SMEC) is a rare subtype of mucoepidermoid carcinoma (MEC), first described in 1987 by Chan and Saw. As far as we are aware, only 30 cases have been published since then. Most cases were located in the parotid gland with some cases described in the submandibular and minor salivary glands. SMEC typically presents as a long-standing mass, with a non-specific enhancing appearance on imaging and is often non-diagnostic on fine needle aspiration, making pre-operative diagnosis very difficult. It is characterised by dense sclerosis within an otherwise typical MEC, frequently with lymphoid proliferation and eosinophils at the periphery. The histological diagnosis of SMEC can be challenging, as the sclerosis may obscure the other morphological features, which can lead to misdiagnosis. Grading can also be difficult, and the prognostic value of grading for SMEC remains unclear. Herein is described a new case of SMEC, presenting clinically as chronic sialadenitis in the left submandibular gland of a 41 year old male. A brief literature review and the issues surrounding diagnosis and grading are also discussed.

Surgical pathology of cystic lesions of the mediastinum

BACKGROUND

Mediastinal cysts are uncommonly encountered in a pathologist's experience.

AIMS

To study the incidence, location, clinical presentation and histologic subtypes of cysts in the mediastinum.

MATERIALS AND METHODS

Cystic lesions of the mediastinum, surgically excised over a period of 22 years were studied after retrieval of relevant clinical data and slides.

RESULTS

Thirty-nine mediastinal cysts were encountered in the study period. Most of the patients (81.5 %) were symptomatic. Histologically, foregut cysts (19 cases, 50 %) were the most common followed by teratomatous cysts (ten cases, 26.3 %) and thymic cysts (four cases, 10.5 %). Bronchogenic cysts represented 63 % of the fore-gut cysts. Unusual lesions in the form of cystic mediastinal tuberculous lymphadenitis and cystic schwannoma were seen in three patients.

CONCLUSIONS

Despite varied location and histology, clinical presentation of mediastinal cysts are similar. Surgical intervention is the preferred line of management.