Study On Relationship Between Sonographic Characteristics And Pathologic Findings In Rabbit Livers Pre And Post Injection Of Chemotherapeutants

Objective: During ultrasonic examination of patientswith malignant tumors, the patient's liver echo-level isfrequently found increased, mimicking a fatty liver. Somescholars believe that condition is post-chemotherapy" fatty liver,whereas most oncologist do not agree to that viewpoint. In orderto investigate the basic pathologic changes resulting in theincreased hepatic echo level, effects of old and newchemotherapeutic agents on rabbit liver, the animal experimentwas planned and implemented.Methods: 20 rabbits (2.Skg±in weight) were randomlyallocated into two groups. One group was given injection of oldchemotherapeutants (Cyclophosphamide and Addamycin),another group was given injection of new chemotherapeutants(Taxol and Epirubicin).Before and alter drug administratinhepatic function, blood lipids and liver ultrasound wereperformed. Adjuvant therapy for breast cancer was chosen: (1)CA(Cyclophosphamide and Adriamycin) regimen:Cyclophosphamide was given intravenously in a dose of28mg/kg on days 1 and 8. Adriamycin was given intravenously in a dose of 2.2mg/kg on day 2, these two drugs were given 3weeks (1 cycle), stopped 1 week, then continued another 3weeks (2 cycles in total); (2) TE (Taxol and Epirubicin)regimen: Taxol was given intravenously in a dose of 7.5mg/kgon day 1, Adriamycin was given intravenously in a dose of2.8mg/kg on day 2, these two drugs were also given 3 weeks (1cycle), stopped 1 week, then continued another 3 weeks (2cycles in total). Hepatic function, blood lipid, liver sonographyof all rabbits were repeated after 2 cycles of chemotherapeutantadministration. Sonograms were stored in an ultrasoundworkstation for offiine analysis. On the longitudinal section ofrabbit right hepatic lobe (through porta hepatis) 3 echo levelswere obtained with histogram from 3 different locations alongthe right branch of main portal vein. Through dividing the sumof these 3 echo levels by 3, the value was taken as the averagevalue of the right lobe. All data were analyzed (t test) withSPSS 11.0. Finally, all rabbits were executed, the livers weretaken out and stored in Formalin solution for pathologicobservation. The results of pathologic changes were analyzedwith Fisher's exact test.Results: The average rabbit hepatic echo level pre and postinjection in old drug group were respectively 25.644±7.82 and46.63±7.54, a statistically significant difference wasobserved (p＜0.05). In new drug group, the average rabbithepatic echo level pre and post injection were respectively 23.02±5.68和30.48±6.44, a statistically significant difference was also observed (p＜0.05). Comparing with that of the postinjection in new drug group, the echo level of rabbit liver of postinjection in old drug group was higher (p＜0.05). Besides theincreased echo level of the parenchyma, liver texture becamecoarse, the walls of the blood vessels and bile ducts werebrighter. In one rabbit liver an echogenic lesion wasvisualized, which Was confirmed as a focal necrosis associatedwith calcification. Pathologic changes in rabbit liver weremainly cloudy swelling and hydropic swelling in both 2groups. Other lesions in old drug group included inflammatorycells infiltration appeared in 6 rabbit livers, focal necrosis in 6,sinusoid dilation plus congestion in 9, ballooning degenerationin 3, Councilman body in 5, focal calcification in 2, fattydegeneration in 6, fibroblast hyperplasia in 2, while new druggroup had sinusoid dilation plus congestion in 5 rabbit livers,inflammatory cells infiltration in 1, Councilman body in 1, focalnecrosis in 2, ballooning degeneration in 3, fatty degeneration in3, fibroblast hyperplasia in 1.Old drug group had 8 irreversiblepathologic changes (necrosis, calcification), new drug grouphad 2 such changes. The difference in irreversible pathologicchanges between these two groups was statistically significant(p＜0.05). All rabbits in old drug group and new drug groupshowed elevated AST or ALT values after drug administration.Blood lipids were within normal limit.Conclusions: 1 After injection of chemotherapeutantsrabbit liver echo level can be increased with coarse liver texture, and brighter walls of the blood vessels and bile ducts. Thesesonographic characteristics are caused by those pathologicchanges such as cloudy swelling, hydropic swelling,inflammatory cells infiltration, focal necrosis, sinusoid dilationplus congestion, ballooning degeneration, fatty. degenerationand focal calcification.2 The intensity of rabbit liver echo level differs in accordancewith different chemotherapeutant. It depends on dosage, durationof administration, and the drug recipient.3 Fatty degeneration is not the only cause that results in theincreased echo level of liver sonographiclly. Pathologic changeslike cloudy swelling, inflammatory cell infiltration, focalnecrosis, sinusoid dilation plus congestion, ballooningdegeneration and focal calcification are other contributingfactors.4 After administration of chemotherapeutants, transaminasesare usually elevated, whereas blood lipids are not inevitablyelevated.5 Pathologic lesions of rabbit liver in new drug group arelighter than those in old drug group. This fact strongly suggeststhat new chemotherapeutants are recommended.