Stage

: The extent of a cancer, especially whether the disease has spread from the original site to other parts of the body. See also staging.

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1. A period in the course of a disease; a description of the extent of involvement of a disease process or the status of a patient with a specific disease, as of the distribution and extent of dissemination of a malignant neoplastic disease; also, the act of determining the s. of a disease, especially cancer. SEE ALSO: period. 2. The part of a microscope on which the microslide bears the object to be examined. 3. A particular step, phase, or position in a developmental process.For psychosexual stages, see entries under phase. [M.E. thr. O. Fr. estage, standing-place, fr. L. sto, pp. status, to stand]

- algid s. the s. of collapse in cholera.

- Arneth stages a differential grouping of polymorphonuclear neutrophils in accordance with the number of lobes in their nuclei, i.e., cells with 1, 2, 3, 4, or 5 (or more) lobes are designated, respectively, as class I, II, and so on. SEE ALSO: Arneth formula.

- bell s. third s. of tooth development, wherein the cells form the inner enamel epithelium, the stratum intermedium, the stellate reticulum, and the outer enamel epithelium; the enamel organ assumes a bell shape.

- bud s. first s. of tooth development; development of the primordia of the enamel organs, the tooth buds.

- cap s. second s. of tooth development wherein there is development of the inner and outer enamel epithelium.

- cold s. the s. of chill in a malarial paroxysm.

- defervescent s. defervescence.

- end s. the late, fully developed phase of a disease; e.g., in end-s. renal disease, a shrunken and scarred kidney that may result from a variety of chronic diseases that have become indistinguishable in their effect on the kidney.

- eruptive s. the s. of an exanthematous illness in which the rash appears.

- exoerythrocytic s. developmental s. of the malaria parasite (Plasmodium) in liver parenchyma cells of the vertebrate host before erythrocytes are invaded. The initial generation produces cryptozoites, the next generation metacryptozoites; reinfection of liver cells from blood cells apparently does not occur. Delayed development of the sporozoite (hypnozoite) of Plasmodium vivax and P. ovale appears to be responsible for malarial relapse that may occur with these disease agents.

- genital s. referring to the psychic organization derived from, and which is characteristic of, the Freudian genital period of the infant's psychosocial organization. See genitality. SEE ALSO: anality, orality.

- imperfect s. a mycologic term used to describe the asexual life cycle phase of a fungus. See anamorph.

- incubative s. SYN: incubation period (1).

- intuitive s. in psychology, a s. of development, usually occurring between 4 and 7 years of age, in which a child's thought processes are determined by the most prominent aspects of the stimuli to which the child is exposed, rather than by some form of logical thought.

- s. of invasion SYN: incubation period (1).

- stages of labor labor.

- latent s. SYN: incubation period (1).

- perfect s. a mycologic term used to describe the sexual life cycle phase of a fungus in which spores are formed after nuclear fusion. SYN: teleomorph.

- preconceptual s. in psychology, the s. of development in an infant's life, prior to actual conceptual thinking, in which sensorimotor activity predominates.

- prodromal s. early s./symptoms of disease prior to the appearance of characteristic symptoms.

- resting s. the quiescent s. of a cell or its nucleus in which no karyokinetic changes are taking place. SYN: vegetative s..

- Tanner s. a s. of puberty in the Tanner growth chart, based on pubic hair growth, development of genitalia in boys, and breast development in girls.

- trypanosome s. trypomastigote.

- tumor s. the extent of the spread of a malignant neoplasm from its site of origin. SEE ALSO: TNM staging.

- vegetative s. SYN: resting s..

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stage 'stāj n

1) a period or step in a process, activity, or development: as

a) one of the distinguishable periods of growth and development of a plant or animal <the larval \stage of an insect>

b) a period or phase in the course of a disease <the rash \stage of Lyme disease (R. H. Boyle)> also the degree of involvement or severity of a disease <advanced \stage II or III disease (more than 10 positive lymph nodes found after axillary dissection) (M. S. Anscher )(et al)>

c) one of two or more operations performed at different times but constituting a single procedure <a two-stage thoracoplasty>

d) any of the four degrees indicating depth of general anesthesia

2) the small platform of a microscope on which an object is placed for examination

stage vt, staged; stag·ing to determine the phase or severity of (a disease) based on a classification of established symptomatic criteria also to evaluate (a patient) to determine the phase, severity, or progression of a disease

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vb.

(in oncology) to classify a primary tumour by its size and the presence or absence of metastases. In addition to clinical examination, a variety of imaging and surgical techniques may be employed to provide a more accurate assessment. Staging tumours is of importance in prognosis and defining appropriate treatment. See also TNM classification.

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(stāj) 1. a period or distinct phase in the course of a disease, the life history of an organism, or any biological process. See also staging. 2. the platform of a microscope on which a slide is placed for viewing of the specimen.