Radiotherapy for oesophagus carcinoma: the impact of p53 on treatment outcome.
OBJECTIVE
Wildtype p53 protein plays an important role in the cellular response to ionizing radiation and other DNA damaging agents and is mutated in many human tumours. We evaluated the relationship of the immunohistochemically determined p53 protein status and the disease control with radiotherapy alone for carcinoma of the oesophagus.


METHODS
Immunostaining for p53 protein was performed on paraffin-embedded specimens from 69 patients with adeno- and squamous cell carcinoma of the oesophagus. All patients were treated by radiotherapy exclusively, consisting of a combination of external irradiation and intraluminal brachytherapy, using two different dose levels.


RESULTS
Fifty-four percent (37/69) of the tumours showed overexpression of the p53 protein. No difference in pre-treatment parameters for p53-positive and p53-negative cases was detected. In multivariate analysis p53 was significantly associated with overall survival (OS) next to weight loss, tumour stage and N-stage. For metastatic-free survival (MFS) p53 status proved to be the sole independent prognostic factor. The influence of p53 on local recurrence-free survival (LRFS), however, was not as strong as on OS and MFS.


CONCLUSIONS
Immunohistochemically detected overexpression of mutated p53 protein in oesophagus carcinoma was an independent prognostic factor in a group of patients treated with radiotherapy alone.
Pomp
J
J
Department of Radiation Oncology, Reinier de Graaf Gasthuis/Diagnostic Centre SSDZ, Delft, The Netherlands.
Davelaar
J
J
Blom
J
J
van Krimpen
C
C
Zwinderman
A
A
Quint
W
W
Immerzeel
J
J
D000230:Adenocarcinoma / Q000378:metabolism / Q000473:pathology / Q000532:radiotherapy*; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000378:metabolism / Q000473:pathology / Q000532:radiotherapy*; D004938:Esophageal Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D011836:Radiation Tolerance / Q000502:physiology*; D011877:Radionuclide Imaging; D016896:Treatment Outcome; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis / Q000502:physiology*
D016159:Tumor Suppressor Protein p53