Tehran University Medical Journal

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Background: Recently the use of “two tier" grading system in which ovarian serous carcinoma was classified as low-grade or high-grade in comparing to preceding system has improved authority in prognosis and survival. This approach is simplistic, reproducible, and based on biologic evidence. In this study, we reclassified ovarian serous carcinoma by a new two-tier system for grading and then evaluation of P53 expression in these tumors by immunohistochemistry method. Methods: We retrospectively reviewed 32 cases of ovarian serous carcinoma with previous diagnosis of well differentiated (eight cases) and moderate to poorly differentiated serous carcinoma (24 cases) and according "two tier" grading system in low-grade vs. high-grade serous carcinoma reclassified. Subsequntly all cases immunostained by P53 marker. Also clinical data related to survival of patients (with or without recurrence of tumor and death) and paraclinical findings such as presurgical blood serum level of CA125 are gathered. Results: Out of total eight patients with previously diagnosis well diferentiated serous carcinoma and of 24 patients with moderate to poorly differentiated serous carcinoma reclassified as low-grade and high-grade ovarian serous carcinoma respectively and a statistically significant difference was found between two groups. (P<0.005) Also of total 24 cases with high grade serous carcinoma, in 12 cases (54%) P53 immunostaining was detected but in non of all low grade serous carcinoma was seen. All 8 low grade serous carcinoma were alive without recurrence of tumor. In 10 and 12 out of 24 cases with high grade serous carcinoma recurrence of tumor and death were seen respectively. Conclusion: Since the presence of P53 negative expression in all of low-grade serous carcinoma by immunostaining and low-grade serous carcinoma accounts for small pupulation of all ovarian serous carcinoma and also few cases in our study, we did not find significant differences between P53 expression and survival in two low-grade vs high-grade serous carcinoma groups.

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Background: This study investigated compatibility between post chemoradiation magnetic resonance images and histologic findings after operation and chemoradiation in patients with locally advanced rectal cancer.

Methods: In this prospective study, 63 patients referred to Cancer Institute of Emam Khomeini Hospital, Tehran, Iran, from October 2011 to October 2013 with locally advanced rectal cancer receiving neoadjuvant chemoradiation (50.4 Gy external beam radiation with concomitant capecitabine 825 mg/m2 PO twice a day with or without 60 mg/m2 oxaliplatin weekly). Patients had an MRI before chemoradiation and MRI assessment were used to identify Tumor (T) and lymph node (N) staging by an experienced radiologist. Patients were recommended to repeat MRI after surgery but it was not obligatory. Findings of post chemoradiation MRI and histopathologic reports were compared. Downstaging was defined as at least one stage decrease in T or N in histopathologic report comparing to their first MRI, on condition of no sign of disease progression.

Results: 32 patients (50.79%) had T downstaging and 36 of them (57.14%) showed N downstaging: none had disease progression. In this study MRI had an accuracy of 55.5% for rectal tumor (T) restaging after chemoradiation comparing to pathology. MRI sensitivity for T restaging was 33.3% to 83.3%.  There was a higher possibility to have errors in restaging of T1-2 stages. Specificity of MRI for T restaging was higher than its sensitivity, 66.6%. In this study lymph node involvement (N) was determined according to morphology and size. MRI has an accuracy of 42.8% for detecting lymph node involvement. Its sensitivity and specificity for N restaging were 50% and 66.6% respectively. All patients had MRI before chemoradiation, although 21 of them repeated MRI after chemoradiation since it was not mandatory. 19 of these 21 patients underwent surgery.

Conclusion: Although MRI is a suitable imaging for staging locally advanced rectal cancer its use for restaging after chemoradiation is under question. According to this study, MRI accuracy rates for both T and N restaging were below the rates of previous studies.