The findings of this lesion indicate, however, apparent malignancy of the tumor with the small original site in the mucosa EX 527 purchase invading down continuously into the submucosa forming a larger submucosal nodule as a result. Thus, the lesion is a malignant epithelial tumor, namely a carcinoma, but not a “”carcinoma-like”" tumor of benign nature that was initially described as a carcinoid. Extraglandular
microcarcinoid in a form of “”budding”" All gastrointestinal “”carcinoids”" are malignant at their very beginning, “”budding”" stage, of neoplastic formation. The early developmental process of carcinoid formation may be hypothetically divided into three stages as shown in Table 1. Table 1 Microproliferation of argyrophil cells PLX3397 in vitro [2] I Hyperplastic: Intraglandular II Preneoplastic: Intraglandular III Neoplastic IIIa Intraglandular IIIb Extraglandular (“”budding”": microinvasion) Extraglandular neoplastic formation starts with a form of CFTRinh-172 purchase “”budding”" (IIIB). An observation on consecutive serial sections of the glandular stomach of an experimental animal clearly indicates that the extraglandular microproliferation of argyrophil cells (IIIB) is a malignant lesion as a “”microcarcinoid”" at its very beginning of neoplastic formation
in a form of “”budding”" as indicated in Fig. 3A–C in the article [2]. Such a developmental process of invasion prior to metastases is thought to be identical to the process in other organs not only of the other Isotretinoin sites of the gastrointestinal tract, but also in other sites including the extradigestive organs. A comparison of metastasis rates in early stage: sm-lesions of carcinoids and ordinary carcinomas Malignancy
represented by metastasis rates in early stages with depth of invasion of the lesions restricted within the submucosa (sm-lesion) is discussed in a statistical comparison between two groups of carcinoid (n = 1158) and ordinary carcinoma (n = 1141) in Table 9 of the article [3]. In the stomach, the metastasis rates of the two groups of carcinoid versus ordinary carcinoma are calculated as 21.4% versus 3.1% in the size range category of 10.1 mm – 20.0 mm (p < 0.0001). In the rectum, the metastasis rates of these two groups are described as 27.6% versus 10.0% in the same size category (p < 0.05), and as 32.4% versus 9.8% in the size range category over 10.1 mm as a whole (p < 0.0001). These results show that early stage carcinoids, with two prescribed factors of depth of invasion restricted within the submucosa and tumor size range of 1 cm to 2 cm, metastasize earlier than ordinary carcinomas with the identical description in both the stomach and rectum.