Are All Stomach Cancers The Same?

All stomach (gastric) cancers are not the same!

Unless a specific histopathological type is mentioned, "stomach cancer" means "stomach adenocarcinoma". Stomach adenocarcinomas histological types can be “papillary”, “tubular”, “mucinous” and “signet ring cell”. Stomach cancers which are less common and whose clinical-pathological features and treatment methods are quite different from adenocarcinomas, are as follows gastrointestinal stromal tumors (GISTs), neuroendocrine tumors, lymphomas and rare types (squamous cell carcinoma, small cell carcinoma, leiomyosarcoma etc.).

Stomach cancer can occur in any anatomical region of the stomach. The area where it develops the most is the lesser curvature, the antrum region. Cardia and fundus tumors (in a broader definition, tumors located in the upper 1/3 of the stomach) are referred to as proximal stomach cancers. Proximal cancers tend to be more biologically aggressive, with a worse prognosis than distal cancers.

According to their macroscopic appearance stomach cancers can be grouped into four types. These are ulcerated (penetrating), polypoid (vegetant), ulcero-vegetant, infiltrating (linitis plastica) types.

Stomach adenocarcinomas may have different degrees or levels of differentiation/grade. These are well differentiated (grade 1, intestinal), moderately differantiated (grade 2, intestinal+diffuse) and poorly differantiated or undifferantiated (grade 3, diffuse) types.

Finally, the stage/extent of stomach cancer at diagnosis may also vary from person to person. Tumor cells can be limited to the mucosa (Tis) or have reached/invaded muscularis mucosa (T1a), submucosa (T1b), muscularis propria (T2), subserosa (T3), serosa or adjacent organs/structures (T4), nearby lymph nodes (N1-2-3) or distant organs (M1).