Karyotype

A blood test to check for the number of chromosomes in cells

Klinefelter's Syndrome

A chromosome problem that causes low testosterone levels, breast development, small testes and infertility in men

Lesion

A change in body tissue caused by disease or injury

Levitra®

Brand of oral PDE5 inhibitor which treats erectile dysfunction by promoting the body's natural response to sexual stimulation

Leydig cells

The testicular cell that produces the male hormone testosterone

Libido

Sex drive

Localised

Cancer that remains in the location where the first lump or growth developed and has not yet spread throughout the body

Luteinizing hormone (LH)

A hormone produced by the pituitary gland which stimulates the production of testosterone in the testes

Lymph node

Small oval structures that filter the lymph and fight infection. Found in the groin, abdomen, neck, armpit and other sites.

Lymphadenopathy

Disorder characterised by a localised/generalised enlargement of the lymph nodes

Lymphoma

Cancer that happens in lymph nodes or other lymph tissues

Macroscopic

Big enough to see with the eye.

Magnetic resonance imaging scan (MRI)

A specialised non-invasive medical imaging process, which does not use x-rays, to diagnose a wide range of diseases

Male menopause

A  term often used to describe androgen deficiency which falsely implies a similarity between female and male hormonal decline later in life

Malignant

Potentially fatal cancerous cells that may spread through the body if not treated

Maturation

Becoming mature

Mediastinum

The centermost part of the chest, between the ribs and spine (front to back) and between the lungs

Menopause

Ceasing of menses (periods) in women only

Metabolic

Relating to the physical and chemical processes of the body

Metabolite(s)

Substances produced by body functions

Metastasis

Cancer cells spread from one part of the body to another

Metastatic

Cancer that has spread to another location in the body; a secondary deposit of cancerous cells

Micropenis

Abnormal smallness of the penis.  Micropenis occurs when the penis fails to grow for the last two-thirds of the embryo's development

Microscopic

Extremely small and not visible by the naked eye.

Morbidity

An illness or abnormal condition

Mutation

An unusual change in the genetic material of a cell

Nanomolar

Unit of measurement

Necrosis

Death of cells or tissue

Needle biopsy

The removal of a piece of living tissue for microsopic examination by inserting a hollow needle through the skin and into the tissue

Neoplasm

Abnormal growth of tissue

Nephrectomy

Surgical removal of a kidney

Nitrate

Type of drug which contains nitric acid

Nocturia

A need to pass urine more than twice at night

Non-seminoma

A type of testicular cancer that forms in specialised sex cells called germ cells (precursors of the sperm-forming cells)

Oestradiol

The major female sex hormone produced by the ovary.

Oestrogen

One of a group of female sex hormones (including oestradiol) that controls the development of female secondary sex characteristics and promotes the growth and maintenance of the female reproductive system.  Oestrogens are made mainly by the ovary, but also in the placenta and small amounts in the testis

Oligozoospermia (or oligospermia)

A very low number of sperm present in the seminal fluid

Oncologist

A doctor who specialises in the treatment of various types of cancer

Oncology

Study and treatment of cancer

Oocytes

A female germ cell in the ovary; a developing egg cell.

Oral medication

Tablet or capsule

Orchidectomy

Surgery to remove one or both testes

Orchidopexy

An operation to lower an undescended testicle and stitch it into the scrotum

Orchitis

Infection of the testes

Orgasm

Culmination of sexual excitement, usually accompanied by ejaculation in the male

Osteoporosis

Thinning of bones which leads to a greater chance of fracturing bones

Ovulation

The process by which an egg is released from the ovary