RESUMO
Non-Hodgkin lymphoma (NHL) of the thyroid is a very rare condition. Swelling of the neck is the usual presentation among patients. Of all thyroid malignancies, only a very small portion accounts for NHL of the thyroid. Here, we present two cases of diffuse large B-cell NHL of the thyroid. Preoperative diagnosis helps in the management of patients with chemotherapy, but in rare cases, surgical removal of the thyroid is done to reduce obstructive symptoms. The diagnosis is usually made based on fine-needle aspiration cytology and biopsy with immunohistochemistry. In these two cases, the patients presented with a history of a rapidly growing mass in the neck for three to four months, but the treatment modalities differed. In one of the cases, the patient received six cycles of chemotherapy, and in the other case, the patient underwent a total thyroidectomy, followed by six cycles of chemotherapy, though chemotherapy is the standard treatment option over surgical removal of the thyroid.
RESUMO
INTRODUCTION: Colorectal cancer is one of the malignancies in which angiogenesis has been implicated and its importance at different stages of malignant disease. Neovascularization begins when the angiogenic switch is turned on and when angiogenesis activators outweigh angiogenic inhibitors. The process of blood vessel formation is regulated through several growth factor systems. The vascular endothelial growth factor (VEGF) system is one of the important ones and may consequently be a key system in relation to different aspects of colorectal carcinoma treatment. Because of the well-defined steps in its progression (adenoma - Tis - T1 invasive cancer- T2 advanced cancer with metastases), colorectal cancer (CRC) represents a model for investigating the effects of angiogenesis throughout tumor development. The aim of this study is to determine the role of VEGF expression by immunohistochemistry (IHC) in normal epithelium, dysplasia, carcinoma of colorectal specimens and to correlate the same with tumor grade, stage, nodal status, and metastasis. METHODS: This is a retrospective study on paraffin blocks of 50 colon cancer specimens, 40 adenoma specimens, and 10 normal colonic mucosa specimens. Immunohistochemical stain for VEGF was done on the sections along with controls. Monoclonal antibody detected against VEGF antigen was observed in the cytoplasm of the tumor cells and the intensity of VEGF expression in individual tumor cells was scored on a scale of 0 (no staining) to 3 (strong intensity), and the percentage of cells with VEGF staining at each intensity was estimated from 0 to 100. Pearson's Chi-squared test and Mann-Whitney test were used to determine significant clinicopathological differences between VEGF expression in positive and negative tumors. RESULTS: In normal epithelium, VEGF immunoreactivity was seen in all 10 cases with high intensity. Among adenomas, VEGF expression was seen in 26 (65%) of the 40 cases. Out of which in tubular adenomas VEGF expression was seen in 13 cases (60%) and negative in eight cases (40%). In tubulo villous adenoma, VEGF expression was seen in nine cases (60%) and negative in six cases (40%). Villous adenomas showed VEGF expression in all four cases (100%). In adenocarcinoma, VEGF expression was seen to be expressed in 42 cases (84%) and negative in eight cases (16%) and expression was higher in low-grade carcinomas (70%) compared to high-grade carcinomas. A significant difference in the expression of VEGF among adenomas and carcinomas was observed with higher intensity present in adenoma when compared to carcinoma. CONCLUSION: Expression of VEGF could be considered as an early carcinogenic factor in colorectal carcinomas as it is expressed in higher intensity in the precancerous lesion and low-grade and stage 1 adenocarcinoma. Hence, we infer that early colorectal carcinomas are an important model for targeted therapy with antiangiogenic factors for VEGF.
