Chemotherapy, Chemotherapy

With succeeding generations of tumor cells, differentiation is typically lost, growth becomes less regulated, and tumors become less responsive to most chemotherapeutic agents. Near the center of some solid tumors, cell division has effectively ceased, making them insensitive to chemotherapy. Another problem with solid tumors is the fact that the chemotherapeutic agent often does not reach the core of the tumor. Solutions to this problem include radiation therapy (both brachytherapy and teletherapy) and surgery.

Chemotherapy may be given with a curative intent or it may aim to prolong life or to palliate symptoms.

In some cases, isolated limb perfusion (often used in melanoma), or isolated infusion of chemotherapy into the liver or the lung have been used.

For continuous, frequent or prolonged intravenous chemotherapy administration, various systems may be surgically inserted into the vasculature to maintain access. Commonly-used systems are the Hickman line, the Port-a-Cath or the PICC line. These have a lower infection risk, are much less prone to phlebitis or extravasation, and abolish the need for repeated insertion of peripheral cannulae.

U. Rther, C. Nunnensiek, H.-J. Schmoll, Secondary Neoplasias following Chemotherapy, Radiotherapy,and Immunosuppression ,Contributions to Oncology (Beitrge zur Onkologie); Vol 55, 2000, ISBN 380557116X Other studies have shown a 13.5 fold increase from the general population in the incidence of secondary neoplasm occurrence after 30 years from treatment. Hijiya, Hudson, Lensing et al.

These drugs are designed to block one or more of the signals that cause nausea and vomiting. The most sensitive signal during the first 24 hours after chemotherapy appears to be 5-HT 3 . Blocking the 5-HT 3 signal is one approach to preventing acute emesis (vomiting), or emesis that is severe, but relatively short-lived. Approved 5-HT 3 inhibitors include Dolasetron (Anzemet), Granisetron (Kytril, Sancuso), and Ondansetron (Zofran). The newest 5-HT 3 inhibitor, palonosetron (Aloxi), also prevents delayed nausea and vomiting, which occurs during the 2-5 days after treatment. A granisetron transdermal patch (Sancuso) was approved by the FDA in September 2008. The patch is applied 24-48 hours before chemotherapy and can be worn for up to 7 days depending on the duration of the chemotherapy regimen.

Source: Wikipedia > Chemotherapy