Pancreatic carcinosarcoma with the same KRAS gene mutation in both carcinomatous and sarcomatous components: molecular evidence for monoclonal origin of the tumour.
OBJECTIVE
To better understand the histogenesis, prognosis and feasible treatment of pancreatic carcinosarcoma, a rare type of neoplasia.


RESULTS
We investigated eight additional cases of pancreatic carcinosarcoma at a single institution, including the clinicopathological, immunohistochemical, and KRAS mutation characteristics. We have also reviewed the current literature on this rare type of neoplasia, and summarized the clinicopathological features and feasible treatments. As a result, concordant strong nuclear immunoreactivity for P53 protein and the same type of KRAS gene mutation, c.35G>A (p.G12D) or c.35G>T (p.G12V), were showed in both carcinomatous and sarcomatous components in five of eight cases. Furthermore, we found that the patients treated with surgery plus postoperative chemotherapy had longer survival than those treated with surgery only (P = 0.034 and P = 0.131 for overall survival and disease-free survival, respectively), although Cox regression multivariate analysis indicated that it was not an independent predictor. In addition, we found KRAS mutant allele-specific imbalance in four of our five cases of pancreatic carcinosarcoma, which was associated with advanced disease and a worse prognosis.


CONCLUSIONS
This is the largest panel of cases of pancreatic carcinosarcoma studied so far, including clinicopathological, immunohistochemical and molecular cytogenetic features. Our findings indicate that the tumour could have been of monoclonal origin, and that the sarcomatous components might have arisen from metaplastic transformation of the carcinomatous components. Our results also suggest that surgery plus POC including gemcitabine may be a good choice for patients with pancreatic carcinosarcoma.
Department of Pathology, Fudan University Shanghai Cancer Centre, Shanghai, China.|Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.
Qianming
Q
Bai
Department of Pathology, Fudan University Zhongshan Hospital, Shanghai, China.
Xin
X
Zhang
Department of Pathology, Fudan University Shanghai Cancer Centre, Shanghai, China.|Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.
Xiaoli
X
Zhu
Department of Pathology, Fudan University Shanghai Cancer Centre, Shanghai, China.|Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.
Lei
L
Wang
Department of Pathology, Fudan University Shanghai Cancer Centre, Shanghai, China.|Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.
Dan
D
Huang
Department of Pathology, Fudan University Shanghai Cancer Centre, Shanghai, China.|Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.
Xu
X
Cai
Department of Pathology, Fudan University Shanghai Cancer Centre, Shanghai, China.|Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.
Xiaoyan
X
Zhou
Department of Pathology, Fudan University Shanghai Cancer Centre, Shanghai, China.|Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.
Jian
J
Wang
Department of Pathology, Fudan University Shanghai Cancer Centre, Shanghai, China.|Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.
Weiqi
W
Sheng
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis / Q000235:genetics; D002296:Carcinosarcoma / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D004252:DNA Mutational Analysis; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D053208:Kaplan-Meier Estimate; D061346:Laser Capture Microdissection; D008297:Male; D008875:Middle Aged; D009154:Mutation; D010190:Pancreatic Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D011379:Prognosis; D016016:Proportional Hazards Models; D016283:Proto-Oncogene Proteins p21(ras) / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D014408:Biomarkers, Tumor; C117307:KRAS protein, human; D016283:Proto-Oncogene Proteins p21(ras)
KRAS mutation; P53; pancreatic carcinosarcoma; postoperative chemotherapy