Metastasis of Rectal Carcinoma in Testes and Skin: Case Series

Abstract

Most common sites for metastasis of rectum carcinoma are liver, lung, and peritoneum. Cutaneous and testicular metastasis from rectum is rare. Cutaneous metastasis from colorectal cancer occur less than 4%of patients [1]. The occurrence of cutaneous metastatic disease from colorectal cancer is uncommon and typically signifies widespread disease with poor prognosis [2]. Testicular metastases from colorectal cancers are rare. Metastatic carcinoma of testes are reported in 0.02 % to 2.5 % [3, 4]. Most common sites for primary are prostate [60 %], Melanoma [15 %], and sarcoma [10 %]. Rarely it metastasises from colon and rectum [5 %] [5]. Unusual site metastases of colorectal cancer are rarely detected in clinical practice. Here we report 4 patients of rectal malignancy having unusual site metastasis (Table 1). Table 1 Details of patients Case 1 In this case patient presented with chief complaint of skin nodules on chest and left side of neck since one month (Fig. ​(Fig.1).1). These swellings were mobile, firm, 1–2 cm in size. On histopathological examination Section showed stratified squamous epithelium infiltrated by malignant epithelial tumour cells dispersed in acini as well as tubules. Some of tumour cells show in intracytoplasmic mucin. Few signet ring cells were also evident. On IHC stainng-Primary panel of CK-7 and CK-20 was applied. Tumors showed positive for CK-20 and negative for CK-7and subsequently CDX 2 which was also positive. Thereby confirmed the diagnosis of metastasis from colorectal carcinoma. On further detail history there were altered bowel habit and weight loss but no history of rectal bleeding. Proctoscopic Examination showed a growth in lower rectum and guided biopsy showed infiltrating mucinous adenocarcinoma (signet ring type) of rectum. CECT abdomen showed single metastasis inside the liver. CECT chest was normal. Serum CEA level was 16 ug/L. Patient was on Chemotherapy (FOLFOX 4). Patient succumbed to death after 4 months from time of appearance of skin nodule. Fig. 1 Showing metastatic nodules on neck and chest Case 2 This patient was diagnosed as a case of stage II rectal cancer. Abdominoperineal resection(APR) was done and was on adjuvant chemotherapy. Patient developed skin swellings at upper end of abdomen, chest and on neck after 10 month of surgery. On Excisional biopsy section showed skin lining infiltrated by tumour cells forming glands and acini lined by tumpur cells having high nucleo cytoplasmic ratio, vesicular nuclei and prominent nucleoli and moderate cytoplasm cytoplasm. Few mitotic figures also evident. On IHC staining it was positive for CK-20 and negative for CK-7 and subsequently CDX 2 was also positive. So Metastatic adenocarcinoma arising from colorectal carcinoma was confirmed. Patient died after 18 months of surgery and after 8 months from time of appearance of skin swellings.