Metastatic small cell neuroendocrine carcinoma of the ileo-caecal junction presenting with tumour perforation - case report of a rare tumour at an unusual site with an uncommon presentation, and literature review

Venkatesh Arumuga Nainar; Navin Sundar Arunachalam Jeykumar; Balamourougan Krishnaraj; Rajesh Nachiappa Ganesh; Nanda Kishore Maroju; Venkatesh Arumuga Nainar; Navin Sundar Arunachalam Jeykumar; Balamourougan Krishnaraj; Rajesh Nachiappa Ganesh; Nanda Kishore Maroju

doi:10.48130/git-0025-0009

Figure 1.

(a) Yellow arrow - heterogenous, peripherally enhancing lesion in segments 2, 3 of liver (Hounsfield units: min- 10, max- 120, avg- 84). Green arrow - hyperenhancing circumferential thickening of the terminal ileum and ileo-caecal junction (Hounsfield units: min- 15, max- 100, avg- 60). (b) Red arrow showing thickened enhancing wall of ileo-caecal junction and a light blue arrow showing extraluminal gas pockets (Hounsfield units: min- 600, max- 1000, avg- 890).

Figure 2.

(a) Blue arrow showing a hypodense lesion in the left supra-renal gland. (b) Green arrows showing bilateral hypodense adrenal lesions (Hounsfield units: min- 20, max- 104, avg- 38).

Figure 3.

Emergency limited right hemicolectomy specimen showing the growth involving the ileo-caecal junction.

Figure 4.

(a) Highlights sheets of tumour cells with round to oval nuclei and ill-defined cell membrane. Nuclei exhibits stippled chromatin, with high mitotic and apoptotic activity. Haematoxylin and eosin stain, x 400. (b) Highlights diffuse strong cytoplasmic expression of Synaptophysin in tumour cells, immunohistochemistry with Ventana antibody. Diaminobenzidine stain, x 400. (c) Highlights high proliferation index in tumour cells as exhibited by Ki-67 immunoperoxidase stain, immunohistochemistry with Ventana antibody. Diaminobenzidine stain, x 400.