Which of the following cancer metastasize to brain leastly: March 2011
Ans. D: Prostatic carcinoma The 5 most common primary sites are lung, breast, skin (melanoma), kidney and gastrointestinal tract, accounting for about 80% of all metastases. Some rare tumours (e.g. choriocarcinoma) have a high likelihood of metastasizing to the brain, whereas some more common tumours (e.g. prostatic tumours) almost never grow in the brain, even when they are metastatic to adjacent bone and dura. Prostatic carcinoma Advanced prostate cancer can spread to other pas of the body, causing symptoms. The most common symptom is bone pain, often in the veebrae, pelvis, or ribs. Spread of cancer into other bones such as the femur is usually to the proximal pa of the bone. Prostate cancer in the spine can also compress the spinal cord, causing leg weakness and urinary and fecal incontinence Trophoblastic diseases They comprise a variety of biologically interrelated conditions which form a clinical spectrum consisting of four distinct clinical pathological entities like - Molar pregnancy Invasive mole - Placental site trophoblastic tumours and - Choriocarcinoma Incidence of hydatidiform mole ranges from 1 in 500 in India to 1 in 3000 in USA. Like wise malignant potential of the disease is also higher in Southeast Asia reaching as high as 10-15% compared to 2-4% in west. Some of the hydatidiform moles erode the wall of uterus, burrow into myometrium and may even burst though the uterus into peritoneum and are called invasive mole. Even though locally aggressive, invasive mole does not metastasise. On the other hand choriocarcinoma is rare but one of the most malignant neoplasms arising in the body of uterus. Choriocarcinoma metastasises readily. It is not uncommon to find secondary nodules in the cervix or vagina. The lungs, brain and liver are the distant organs more often involved. Lymph nodes are rarely the site of metastasis Brain metastases They are the most common type of brain tumors, with the total number diagnosed annually outnumbering all other intracranial tumors combined. The most common source of brain metastases in males is lung cancer and in females is breast cancer. The mechanisms by which primary tumors produce brain metastases is thought to be hematogenous spread from primary or secondary sites in the lung. Since the brain has no lymphatic system, all tumors metastasizing to the brain do so by spreading through the bloodstream. Aerial blood passes through the lungs before entering the brain, and collects tumor cells filtered out in capillaries, which subsequently embolize to the brain. Melanoma has the highest tendency to produce multiple lesions, followed by lung and breast cancers.
Hypernephroma
Breast carcinoma
Choriocarcinoma
Prostatic carcinoma