Neoplasm

Definition

This neoplasm is a large B-cell lymphoma with an activated B-cell/non-germinal centre B-cell immunophenotype that arises in skin, particularly the legs.¹

Definition

This neoplasm is defined as a DLBCL arising in the central nervous system (CNS) including the brain, spinal cord, leptomeninges, and eyes. CNS involvement by systemic DLBCL and lymphomas arising in immunosuppressed patients are excluded.¹

Definition

This neoplasm is a large B-cell lymphoma characterised by strong expression of MUM1/IRF4 and associated with IRF4 rearrangement.¹ The histological pattern of these neoplasms can be follicular, follicular and diffuse, or entirely diffuse, with the latter pattern being common and the focus of this discussion.^1,44

1.2 Neoplasm

The term neoplasm is derived from a mixture of two Greek words, “neo” means new, and “plasis” means formation. Neoplasm refers to the abnormal tissue growth, caused due to the uncontrolled or rapid division of cells that have undergone some forms of mutations. Unlike normal cells, the growth of neoplastic cells is autonomous that is, independent of growth factors and regulatory mechanisms that commonly operate inside the normal tissues [3]. The uncontrolled growth of the neoplastic cells usually (but not always) forms a mass. When it forms a mass, it may be called a tumor. A tumor mass may be solid, or fluid-filled and are quite different from inflammatory or other swellings. A tumor mass can be felt as a lump, if it occurs on or near the surface of the body, while some are deep sited and may not be palpated [4]. In some instances, tumors may also appear as ulcers, fissures, or wart-like projections. A tumor can occur anywhere inside the body and its size may vary tremendously [5,6].

Like any other tissues or organs, the growth and architecture of a tumor largely depend upon two basic components, such as parenchyma (composed of neoplastic or tumor cells) and reactive stroma (composed of immune cells, fibroblasts, endothelial cells, and specialized mesenchymal cells). The crosstalk between the parenchyma and stroma forms a tumor microenvironment, which is important in deciding the growth and aggressiveness of a tumor [7,8]. For instance, the stromal blood supply promotes the tumor cell division whereas the stromal connective tissue act as a structural framework for growing tumor cells [9]. It is the stromal deposit that decides the nature of a tumor that is, scanty stromal support develops soft tumors while highly collagenous stromal support develops stony hard tumors [10].

Sometimes, the term tumor and cancer are used interchangeably which can be misleading. People often get scared when they get a tissue mass and immediately interpret whether it is a cancer beginning. After intensive research in medical science, it was quite clear that all tumors are not cancerous. Broadly, tumors are classified according to their nature of growth and aggressiveness as benign (non-cancerous) and malignant (cancerous) tumors. The initiation of tumor development is the same for both benign and malignant tumors, such as single-cell mutation, but with time the metastatic potential of malignant tumors always raises a red flag.

Introduction

The word neoplasm derives from the Greek and is composed of the terms neo, which means new, and plasma, which means formation or creation. The term is used to designate aberrant tissue growth that results from microscopic abnormal cellular proliferation. Such proliferations may result from increased cell division, absence of normal cell death, or both. Neoplasms may occur in situ, that is, confined to the same location where they originally formed in the absence of tumor spread. However, many neoplasms grow to form a macroscopic mass of abnormal tissue. Resultant symptoms and signs bring affected patients to clinical attention.

The term tumor has generally been used as synonymous with neoplasm. The word originates from the Latin tumere, meaning to swell, and refers to a swollen part or protuberance. Thus, tumor can be employed to refer to any space occupying lesion regardless of its etiology, including nonneoplastic conditions. For example, an inflammatory process may produce a swelling or protuberance that may be correctly designated as a tumor.

Neoplasms are subclassified as malignant or benign. Benign neoplasms may grow and produce macroscopic masses but generally do not spread to other organs or lymph node sites. Malignant neoplasms are composed of cells that may invade and destroy adjacent organs and possess the ability to spread to distant organs or lymph node sites. In fact, the ability to metastasize is considered characteristic of a malignant neoplasm.

Terminology

Definitions

NEOPLASM

Based on the 1-year history of very slow progression of clinical signs and the palpation of a mass lesion in the area of the anatomic diagnosis, a neoplasm is the most likely clinical diagnosis. Radiographs determined that a large mass had obliterated most components of the right temporal bone. Splash was euthanized, and necropsy diagnosed this extramedullary temporal bone neoplasm as a basal cell carcinoma (Figs. 12-11 through 12-14).