title: Pseudoprogression in patients with malignant gliomas treated with concurrent temozolomide and radiotherapy: potential role of p53.
abstract: We investigated pseudoprogression (psPD) in patients with malignant gliomas treated with radiotherapy (RT) and maintenance temozolomide (TMZ) in terms of incidence, outcomes, and predictive and prognostic factors. We evaluated p53 overexpression by immunohistochemical analysis of thirty-five tumor samples as a predictor for psPD. The time to progression and overall survival were compared between subgroups, psPD versus early progression (ePD) versus nonprogression (nonPD). Eight patients developed psPD among eighteen patients with lesion enlargement at the first MRI scan, and the others were classified as ePD. The remaining stable or improved patients were classified as nonPD. All patients with psPD were alive at last follow-up (median follow-up period was 12 months; range 5.8-58.5 months). Overall survival of psPD patients was significantly higher than ePD patients (P < 0.01). There was no significant survival difference between the psPD group and nonPD group (P = 0.25). Seven (87.5%) of eight tumors with psPD showed p53 overexpression, as compared to 3 (30%) of the ten tumors with ePD (P = 0.03). Our study indicates that psPD following chemoradiotherapy with TMZ is associated with significantly better overall survival compared to that of ePD, and is comparable to nonPD group. Overexpression of p53 was identified as a potential biomarker for predicting the development of psPD.
authors.affiliation: Department of Radiation Oncology, Seoul National University Bundang Hospital, 300 Gumidong Seongnamsi, Kyeonggido 463-707, Republic of Korea.
authors.forename: Hyun-Cheol
authors.initials: HC
authors.lastname: Kang
authors.forename: Chae-Yong
authors.initials: CY
authors.lastname: Kim
authors.forename: Jung Ho
authors.initials: JH
authors.lastname: Han
authors.forename: Ghee Young
authors.initials: GY
authors.lastname: Choe
authors.forename: Jae Hyoung
authors.initials: JH
authors.lastname: Kim
authors.forename: Jee Hyun
authors.initials: JH
authors.lastname: Kim
authors.forename: In Ah
authors.initials: IA
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018906:Antineoplastic Agents, Alkylating / Q000627:therapeutic use; D001932:Brain Neoplasms / Q000378:metabolism* / Q000473:pathology* / Q000628:therapy; D003131:Combined Modality Therapy; D003606:Dacarbazine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D005910:Glioma / Q000378:metabolism* / Q000473:pathology* / Q000628:therapy; D006801:Humans; D007124:Immunoenzyme Techniques; D015994:Incidence; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D018714:Radiotherapy, Adjuvant; D015996:Survival Rate; D000077204:Temozolomide; D016896:Treatment Outcome; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*; D055815:Young Adult
chemical_list: D018906:Antineoplastic Agents, Alkylating; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53; D003606:Dacarbazine; D000077204:Temozolomide