I hope you do not need to know about chemother­apy. If you stum­ble upon this word because you or loved ones need to be treated for can­cer or other con­di­tions, there is much more you need to know about chemother­apy than its just not a pleas­ant treat­ment. Chemother­apy is a group of med­ica­tion that tar­gets rapidly divid­ing cells in our body. More­over, they inter­act with some cells lead­ing the cell to its demise.
First watch that video this pro­motes can­cer aware­ness in young peo­ple.

Chemother­apy Classification

Alky­lat­ing agents
There are sev­eral types of alky­lat­ing agents agents:

• Mus­tard gas deriv­a­tives:  Mechlorethamine, Cyclophos­phamide, Chlo­ram­bu­cil, Mel­pha­lan, and Ifosfamide.
• Eth­yl­en­imines:  Thiotepa and Hexamethylmelamine.
• Alkyl­sul­fonates:  Busulfan.
• Hydrazines and Tri­azines: Altre­t­a­mine, Pro­car­bazine, Dacar­bazine and Temozolomide.
• Nitro­sureas:  Car­mus­tine, Lomus­tine and Strep­to­zocin.  Nitro­sureas are unique because, unlike most types of chemo treat­ments, they can cross the blood-brain bar­rier.  They can be use­ful in treat­ing brain tumors.
• Metal salts:  Car­bo­platin, Cis­platin, and Oxaliplatin.

Plant Alka­loids
Derived made from cer­tain types of plants.

• Vinca alka­loids: Vin­cristine, Vin­blas­tine and Vinorelbine.
• Tax­anes:  Pacli­taxel and Docetaxel.
• Podophyl­lo­tox­ins:  Etopo­side and Tenisopide.
• Camp­tothecan analogs: Irinote­can and Topotecan.

Anti­tu­mor Antibi­otics
Made from nat­ural prod­ucts pro­duced by species of the soil fungus .

• Anthra­cy­clines:  Dox­oru­bicin, Daunoru­bicin, Epiru­bicin, Mitox­antrone, and Idarubicin.
• Chro­momycins:  Dactin­o­mycin and Plicamycin.
• Mis­cel­la­neous:  Mit­o­mycin and Bleomycin.

Antimetabo­lites
When the cells incor­po­rate these sub­stances into the cel­lu­lar metab­o­lism, they are unable to divide.

• Folic acid antag­o­nist:  Methotrexate.
• Pyrim­i­dine antag­o­nist:  5-Fluorouracil, Fox­uri­dine, Cytara­bine, Capecitabine, and Gemcitabine.
• Purine antag­o­nist:  6-Mercaptopurine and 6-Thioguanine.
• Adeno­sine deam­i­nase inhibitor:  Cladrib­ine, Flu­dara­bine, Nelara­bine and Pentostatin.

Topoi­so­merase inhibitors
Inter­fere with the action of topoi­so­merase enzymes, nec­es­sary for DNA replication.

• Topoi­so­merase I inhibitors:  Ironote­can, topotecan
• Topoi­so­merase II inhibitors:  Amsacrine, etopo­side, etopo­side phos­phate, teniposide

Mis­cel­la­neous Anti­neo­plas­tics
Sev­eral use­ful types of chemother­apy drugs are unique:

• Ribonu­cleotide reduc­tase inhibitor:  Hydroxyurea.
• Adreno­cor­ti­cal steroid inhibitor:  Mitotane
• Enzymes:  Asparag­i­nase and Pegaspargase.
• Antimi­cro­tubule agent:  Estramustine
• Retinoids:  Bexarotene, Isotretinoin, Tretinoin

Beyond these, many other types of treat­ments exist, such as tar­geted ther­apy, immunother­apy, and hor­mone ther­apy. You can find a more com­pre­hen­sive list of cer­tain drug or com­bi­na­tion used for cer­tain can­cers here.

Effect of chemother­apy on ovar­ian reserve. Egg reserve is deter­mined mainly by the num­ber of small non-growing fol­li­cles in the ovary (pri­mor­dial fol­li­cles con­tain more than 85% of eggs in the ovary). This effect is depen­dent on

1. Type of drug; alky­lat­ing agents has more harm­ful effect than other chemother­a­peu­tics. Some physi­cians clas­sify the effects on treat­ment on fer­til­ity based on the type of drug used only into high risk e.g cyclophos­phamide, inter­me­di­ate risk e.g cis­plat­inum, low risk e.g methotrex­ate and unknown e.g pacli­taxel. This clas­si­fi­ca­tion, how­ever, does not take in con­sid­er­a­tion other impor­tant factors
2. Age; gen­er­ally younger women have more fol­li­cles in their ovaries than older women. They are thus more likely to retain some fol­li­cles after chemotherapy.
3. Com­bi­na­tion of drugs; com­monly mul­ti­ple drugs are used simul­ta­ne­ously and add to the dam­ag­ing effect on pri­mor­dial follicles.
4. Total dose; usu­ally given as in mg per body sur­face area.
5. Fre­quency of administration
6. Den­sity of dose; admin­is­ter­ing chemother­apy cycle more fre­quently e.g repeat­ing the cycle of med­ica­tions every 2 weeks instead of 3 weeks.
7. Genet­ics; cer­tain enzymes are respon­si­ble for detox of chemother­apy. Some indi­vid­u­als inherit a weaker or slower form of the enzyme. The drug used is then not elim­i­nated as fast as in indi­vid­u­als car­ry­ing the nor­mal form of the enzyme.
8. Radi­a­tion; expo­sure of the ovary to radi­a­tion fur­ther increases the loss of follicles.

Although a lot of infor­ma­tion is known about the effects of chemother­apy on the ovaries, it is very dif­fi­cult to pre­dict the ulti­mate effects on fer­til­ity. Tests for ovar­ian reserve are help­ful but not very accu­rate. Cer­tainly resump­tion of menses does not reflect fer­til­ity poten­tial after chemotherapy.

Prac­ti­cal steps

• Obtain a list of med­ica­tion from the oncol­o­gist or oncol­ogy nurse, before the start of treatment.
• Read about the effect of your spe­cific treat­ment on future fertility.
• Ask ques­tions about the poten­tial effects of treat­ment on future fer­til­ity. The answer may not be sim­ple. Ask your oncol­o­gist, request con­sul­ta­tion with a repro­duc­tive endocri­nol­o­gist with exper­tise in preser­va­tion of fertility.
• Tests for ovar­ian reserve are usu­ally done (FSH, AMH, ultra­sound..). These also are use­ful for com­par­i­son when repeated after chemotherapy.
• Con­sider options for preser­va­tion of fer­til­ity prior to chemother­apy e.g. embryo freezing
• Keep accu­rate records of your treat­ment. Here is a tool to help you.