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Paper text:
etoposide is a cytotoxic agent ( anticancer drug ) which has been used in the treatment of a variety of malignant conditions .
etoposide is an essential component of chemotherapy in patients with rare gynecological malignancies such as germ cell tumors and gestational trophoblastic disease .
hypersensitivity reactions ( hsr ) to etoposide have been reported in 13% patients . in most patients , reactions arise within 10 min and are treated by discontinuing the infusion and administering antiallergic pharmacologic agents .
there are no suitable substitutes for etoposide in regimens such as emaco ( etoposide , methotrexate , actinomycin d , cyclophosphamide , vincristine ) .
etoposide should only be discontinued when there is severe patient intolerance during a course of treatment , necessitating second - line therapy .
a 39-year - old patient with a diagnosed recurrence of choriocarcionma in the site of vaginal scar tissue and distant metastases in the lungs and brain was admitted for treatment with a standard emaco regimen .
two years earlier , she was diagnosed with choriocarcinoma with lung metastasis and was successfully treated with an emaco regimen ( 8 cycles ) and hysterectomy .
this time , the council for trophoblastic disease prescribed 8 cycles of chemotherapy . on admission , she had severe anemia [ red blood cells 3.89  10/l ( 4.105.10 ) and hemoglobin 73.5 g / l ( 115165 ) ] , which required blood transfusion . during the second dose of blood transfusion ,
the administration of etoposide was commenced ( 200 mg in 500 ml of sodium chloride 0.9% over 60 min ) .
after 20 drops , the patient complained of generalized heat , tightness in the throat , shortness of breath and palpitations .
she was found to be hypotensive ( blood pressure = 100/60 mm hg ) , tachycardic ( pulse rate = 120 beats / min ) and desaturated to 84% on pulse oximetry .
in addition , the anesthesiologist noticed a discrete rush on the hand opposite to that used for transfusion .
the patient was supplemented with oxygen and given fluids , methylprednisolone and diphenhydramine intravenously , which resolved her symptoms rapidly within 45 min .
the following day , the patient received premedication with methylprednisolone ( 60 mg ) , ranitidine ( 50 mg ) and diphenhydramine ( 50 mg ) intravenously .
then , she was given an infusion with sodium chloride 0.9% over 10 min ( placebo ) .
after a few drops of infusion , the patient developed acute dyspnea and chest tightness .
the following day the patient received an equivalent dose of etoposide phosphate intravenously , a water - soluble ester of etoposide , after the same premedication described above .
the etiology and the exact mechanism are unknown , but they are believed to be of nonimmunogenic origin . nevertheless , there are some hypotheses that the concentration of the drug and the rate of infusion could explain hsr . another possible way of hsr is that the additive used in the preparation to dissolve etoposide ( benzyl alcohol , polysorbate 80 ) may cause hsr . in animal models ,
it is a type i reaction and antibody mediated . in our case , it is believed that the patient experienced the same type of reaction since the acute symptoms occurred immediately , as a result of releasing vasoactive substances such as histamine .
it was reported that the substitution of etoposide phosphate in patients with etoposide hsr seems to be appropriate . in the reported case
, we have completed the treatment without any complications after changing to another pharmaceutical form of etoposide .
etoposide phosphate is a water - soluble prodrug of etoposide , and this variant does not require polysorbate 80 to enter solution . to date , hsr to etoposide phosphate has not been reported [ 3 , 7 ] . in our case
, it is likely that polysorbate 80 is a causative factor in the hsr to etoposide .
however , another alternative to avoid any possibility of hsr is the use of oral instead of intravenous etoposide because this has a lower incidence of hsr .
also , a case of successful treatment of choriocarcinoma by diluting the etoposide concentration to half and reducing the drug administration rate by half to avoid hsr is described in the literature .
in situations where a patient expresses hsr to etoposide and where subsequent doses of etoposide are deemed necessary , replacement with etoposide phosphate is a reasonable and viable alternative with antihistamine and corticosteroid premedication .
etoposide is commonly used in the treatment of a variety of neoplasms . 
 hypersensitivity reactions to etoposide are infrequently reported and include hypotension , hypertension , flushing , diaphoresis , chest discomfort , dyspnea , bronchospasm and loss of consciousness . 
 we report the case of a 39-year - old woman who experienced acute bronchospasm , tachycardia , hypoxia and hypotension . 
 the symptoms resolved within an hour after administration of intravenous fluids , methylprednisolone , diphenhydramine and oxygen . 
 subsequently , the patient was given etoposide phosphate without incident .