Reappraisals of biological behaviors of PDGFRA mutant gastrointestinal stromal tumor / 中华病理学杂志

Objective: To investigate the biological behavior spectrum of platelet-derived growth factor alpha receptor (PDGFRA)-mutant gastrointestinal stromal tumor (GIST), and to compare the clinical values of the Zhongshan method of benign and malignant evaluation with the modified National Institutes of Health (NIH) risk stratification. Methods: A total of 119 cases of GIST with PDGFRA mutation who underwent surgical resection at Zhongshan Hospital, Fudan University from 2009 to 2020 were collected. The clinicopathological data, follow-up records, and subsequent treatment were reviewed and analyzed statistically. Results: There were 79 males and 40 females. The patients ranged in age from 25 to 80 years, with a median age of 60 years. Among them, 115 patients were followed up for 1-154 months, and 13 patients progressed to disease. The 5-year disease-free survival (DFS) and overall survival (OS) were 90.1% and 94.1%, respectively. According to the modified NIH risk stratification, 8 cases, 32 cases, 38 cases, and 35 cases were very-low risk, low risk, intermediate risk, and high risk, and 5-year DFS were 100.0%, 95.6%, 94.3%, and 80.5%, respectively. There was no significant difference in prognosis among the non-high risk groups, only the difference between high risk and non-high risk groups was significant (P=0.029). However, the 5-year OS was 100.0%, 100.0%, 95.0% and 89.0%, and there was no difference (P=0.221). According to the benign and malignant evaluation Zhongshan method, 43 cases were non-malignant (37.4%), 56 cases were low-grade malignant (48.7%), 9 cases were moderately malignant (7.8%), and 7 cases were highly malignant (6.1%). The 5-year DFS were 100.0%, 91.7%, 77.8%, 38.1%, and the difference was significant (P<0.001). The 5-year OS were 100.0%, 97.5%, 77.8%, 66.7%, the difference was significant (P<0.001). Conclusions: GIST with PDGFRA gene mutation shows a broad range of biological behavior, ranging from benign to highly malignant. According to the Zhongshan method, non-malignant and low-grade malignant tumors are common, the prognosis after surgery is good, while the fewer medium-high malignant tumors showed poor prognosis after surgical resection. The overall biological behavior of this type of GIST is relatively inert, which is due to the low proportion of medium-high malignant GIST. The modified NIH risk stratification may not be effective in risk stratification for PDGFRA mutant GIST.

Clinicopathological features of gastric alpha-fetoprotein-producing adenocarcinoma with SWI/SNF complex deletion / 中华病理学杂志

Objective: To investigate the clinicopathological features and treatment of gastric alpha-fetoprotein (AFP)-producing adenocarcinoma with SWI/SNF complex deletion. Methods: Four cases of gastric AFP-producing adenocarcinoma with SWI/SNF complex deletion diagnosed in Zhongshan Hospital of Fudan University from January 2021 to December 2022 were collected, and their histomorphological characteristics, immunohistochemical (IHC), in situ hybridization of Epstein-Barr virus-encoded RNA (EBER), next-generation sequencing results, clinicopathological features and treatment were summarized, and literature review was conducted. Results: Among the 4 patients, there were three males and one female. They presented with abdominal pain, belching and melena. Serum AFP was significantly elevated in three patients, and endoscopy showed ulcerative lesions. Microscopically, the tumor cells showed mainly diffuse flaky or nest-like growth and typical characteristics of hepatoid adenocarcinoma. In two cases there were adenoid growth, and the tumor cells in these areas possessed clear cytoplasm, suggesting enteroblastic differentiation. The tumor cell nuclei were pleomorphic with large nucleoli and brisk mitoses. The IHC results showed that the tumor cells expressed AFP, GPC3 and SALL4, and there was retained expression of broad-spectrum keratin (CKpan) and E-cadherin. IHC detection of SWI/SNF complex subunits, namely INI1 (SMARCB1), BRG1 (SMARCA4), BRM (SMARCA2), ARID1A protein was performed. In all four cases the hepatoid adenocarcinoma region and enteroblastic differentiation region showed SMARCA2 deletion, and one case with enteroblastic differentiation also showed ARID1A deletion. SMARCB1 and SMARCA4 deletions were not seen. All the four cases were diffusely positive for p53 protein, and the Ki-67 proliferation index was 80%-90%. There were no mismatch repair deletion detected; one cases showed HER2 was strongly positive (3+), and EBER was negative. None of the four cases had mutations in the SWI/SNF complex-related subunits detected by next-generation sequencing. Among the four patients, two underwent palliative surgery due to distant metastasis at the time of surgery, two underwent radical resection. Postoperative adjuvant chemotherapy was given to three patients. Conclusions: AFP-producing adenocarcinoma is a rare subtype of gastric cancer, which can be combined with SWI/SNF complex deletion, and the pathomorphological manifestations are different from the classical SWI/SNF complex deletion of undifferentiated carcinoma with rhabdoid phenotype.

Clinicopathological features and prognostic factors of gastric intermediate-risk gastrointestinal stromal tumor after surgical resection: a retrospective study / 中华病理学杂志

Objective: To investigate the clinicopathological features, treatment and prognosis of gastric intermediate-risk gastrointestinal stromal tumor (GIST), so as to provide a reference for clinical management and further research. Methods: A retrospective observational study of patients with gastric intermediate-risk GIST, who underwent surgical resection between January 1996 and December 2019 at Zhongshan Hospital of Fudan University, was carried out. Results: Totally, 360 patients with a median age of 59 years were included. There were 190 males and 170 females with median tumor diameter of 5.9 cm. Routine genetic testing was performed in 247 cases (68.6%, 247/360), and 198 cases (80.2%) showed KIT mutation, 26 cases (10.5%) showed PDGFRA mutation, and 23 cases were wild-type GIST. According to "Zhongshan Method"(including 12 parameters), there were 121 malignant and 239 non-malignant cases. Complete follow-up data were available in 241 patients; 55 patients (22.8%) received imatinib therapy, 10 patients (4.1%) experienced tumor progression, and one patient (PDGFRA mutation, 0.4%) died. Disease-free survival (DFS) and overall survival rate at 5 years was 96.0% and 99.6%, respectively. Among the intermediate-risk GIST, there was no difference in DFS between the overall population, KIT mutation, PDGFRA mutation, wild-type, non-malignant and malignant subgroups (all P>0.05). However, the non-malignancy/malignancy analysis showed that there were significant differences in DFS among the overall population (P<0.01), imatinib treatment group (P=0.044) and no imatinib treatment group (P<0.01). Adjuvant imatinib resulted in potential survival benefit for KIT mutated malignant and intermediate-risk GIST in DFS (P=0.241). Conclusions: Gastric intermediate-risk GIST shows a heterogeneous biologic behavior spectrum from benign to highly malignant. It can be further classified into benign and malignant, mainly nonmalignant and low-grade malignant. The overall disease progression rate after surgical resection is low, and real-world data show that there is no significant benefit from imatinib treatment after surgery. However, adjuvant imatinib potentially improves DFS of intermediate-risk patients with tumors harboring KIT mutation in the malignant group. Therefore, a comprehensive analysis of gene mutations in benign/malignant GIST will facilitate improvements in therapeutic decision-making.

Clinical significance of pathological diagnosis and genetic abnormalities detection in gastrointestinal stromal tumor using endoscopic biopsy / 中华病理学杂志

Objective: To investigate the clinical significance of pathological diagnosis and genetic abnormalities detection of gastrointestinal stromal tumor (GIST) using endoscopic biopsy. Methods: Patients with GIST diagnosed by endoscopic biopsy (from January 1st, 2016 to August 1st, 2018, at Zhongshan Hospital, Fudan University) were included in this study. This retrospective study evaluated the histopathologic and immunohistochemical (IHC) features, genetic abnormalities of the tumors and the treatment and clinical course of the patients. Results: Totally 4 095 cases of GIST were collected, among which 67 patients (67/4 095, 1.6%) underwent endoscopic biopsy. Forty-eight patients (71.6%) were male and 19 (28.4%) were female, with a mean age of 61 years (range 31-90 years). Fifty-nine lesions were located in stomach and eight in duodenum. Of all the 67 cases, 47 were spindle type, 14 were epithelioid type, and 6 mixed type. IHC staining showed the positive rates were 100.0% (64/64) for DOG1, 98.4% (62/63) for CD117, 87.5% (56/64) for CD34, 3.6% (2/56) for S-100 protein, 12.1% (7/58) for α-SMA, 12.3% (7/57) for desmin and 4.0% (2/50) for CKpan. Morphologically, 34 cases were malignant; three cases (all epithelioid type) were originally misdiagnosed as poorly differentiated carcinoma; missed-diagnosis were found in four cases (spindle type) due to the insufficient diagnostic tumor cells. The genetic abnormality detection rate in the biopsy tissue was 38.8% (26/67),among them two patients were lost to follow up after biopsy, 33 patients received surgical resection, 16 cases underwent operation after neoadjuvant therapy and 16 patients with advanced disease underwent continuous imatinib therapy, with the genetic testing rate of 6.1% (2/33), 10/16 and 14/16, respectively. Conclusions: Endoscopic biopsy is a useful but rare method for the preoperative diagnosis of GIST. For majority of biopsy, accurate pathological diagnosis and auxiliary examination can be completed to guide clinical treatment. A thorough history in combination with endoscopic finding is essential to avoid misdiagnosis (epithelioid type) and missed diagnosis (spindle type) in suspicious cases. Genetic testing should be recommended in patients who will undergo targeted therapy after endoscopic biopsy, and it can provide valuable information and guidance for clinical treatment.

Clinicopathological features and prognosis of gastrointestinal stromal tumors with KIT/PDGFRA gene "homozygous mutation": a multicenter retrospective cohort study / 中华胃肠外科杂志

Objective: To investigate the clinicopathological features of gastrointestinal stromal tumor (GIST) with KIT/PDGFRA "homozygous mutation", the efficacy of targeted therapy and the prognosis. Methods: A retrospective cohort study and propensity score matching were used. "Homozygous mutation" was defined as the detection of KIT/PDGFRA gene status of GIST by Sanger sequencing, which showed that there was only mutant gene sequence in the sequencing map, lack of wild-type sequence or the peak height of mutant gene sequence was much higher than that of wild-type gene sequence (> 3 times). "Heterozygous mutation" was defined as the mutant gene sequences coexisted with wild type gene sequences, and the peak height was similar (3 times or less). The clinicopathological data and follow-up information of 92 GIST patients with KIT/PDGFRA "homozygous mutation" were collected from 4 hospitals in Shanghai from January 2008 to May 2021 (Renji Hospital, Shanghai Jiaotong University School of Medicine: 70 cases; Zhongshan Hospital, Fudan University: 14 cases; Changhai Hospital, Naval Military Medical University: 6 cases and Ruijin Hospital, Shanghai Jiaotong University School of Medicine: 2 cases). Patients with perioperative death, other malignancies, and incomplete clinicopathological information were excluded. The clinicopathological features of the patients and the efficacy of targeted drug therapy were observed and analyzed. The efficacy was evaluated using Choi criteria, which were divided into complete response (CR), partial response (PR), stable disease (SD) and progressive disease (PD). In addition, a total of 230 patients with high-risk GIST with "heterozygous mutation" in exon 11 of KIT gene and 117 patients with recurrent or metastatic GIST with "heterozygous mutation" in exon 11 of KIT gene were included. The propensity score matching method was used to match GIST patients with "heterozygous" and "homozygous" mutations in exon 11 of KIT gene (1∶1) for survival analysis. The disease-free survival (DFS) between two groups of high-risk GIST patients who underwent complete surgical resection were compared. And progression-free survival (PFS) in patients with recurrent or metastatic GIST were compared. Results: Of the 92 GIST cases with KIT/PDGFRA "homozygous mutation", 58 were males and 34 were females, with a median onset age of 62 (31-91) years. Primary GIST 83 cases. Primary high-risk GIST (53 cases), metastatic GIST (21 cases) and recurrent GIST (9 cases) accounted for 90.2% (83/92). There were 90 cases of KIT gene"homozygous mutation" (exon 11 for 88 cases, exon 13 for 1 case, exon 17 for 1 case), and 2 cases of PDGFRA gene "homozygous mutation" (exon 12 for 1 case, exon 18 for 1 case). The median follow-up time was 49 (8-181) months. Among the 61 cases of primary localized GIST undergoing complete surgical resection, 2 cases were intermediate-risk GIST, 5 cases were low-risk GIST, and 1 case was very low-risk GIST, of whom 1 case of intermediate-risk GIST received 1-year adjuvant imatinib mesylate (IM) therapy after operation, and no tumor recurrence developed during the follow-up period. The remaining 53 cases were high-risk GIST, and follow-up data were obtained from 50 cases, of whom 22 developed tumor recurrence during follow-up. Of 9 patients directly receiving neoadjuvant targeted therapy (IM or avapritinib), 5 had complete imaging follow-up data, and the evaluation of efficacy achieved PR. Of all the 92 GIST cases with KIT/PDGFRA "homozygous mutation", 50 (54.4%) had tumor metastasis or tumor recurrence or progression during follow-up, and 12 (13.0%) died of the tumor. Survival analysis combined with propensity score showed that in 100 cases of high-risk GISTs with complete resection, GISTs with "homozygous mutation" in exon 11 of KIT gene had shorter disease-free survival (DFS) than GISTs with "heterozygous mutation" in exon 11 of KIT gene (median DFS: 72 months vs. 148 months, P=0.015). In 60 cases of recurrent or metastatic GISTs with KIT gene exon 11 mutation, IM was used as the first-line treatment, and the progression-free survival (PFS) of GISTs with "homozygous mutation" was shorter compared to GISTs with "heterozygous mutation" (median PFS: 38 months vs. 69 months, P=0.044). The differences were statistically significant. Conclusions: "Homozygous mutation" in KIT/PDGFRA gene is associated with the progression of GIST. The corresponding targeted therapeutic drugs are still effective for GIST with KIT/PDGFRA gene "homozygous mutation". Compared with GIST patients with "heterozygous mutation" in KIT exon 11, GIST patients with "homozygous mutation" in KIT exon 11 are more likely to relapse after surgery and to develop resistance to IM. Therefore, it is still necessary to seek more effective treatment methods for this subset of cases.

Screening of differentially expressed microRNAs in borderline and malignant gastrointestinal stromal tumors / 中华病理学杂志

<p><b>OBJECTIVE</b>Gastrointestinal stromal tumors (GISTs) have a broad spectrum of biological behaviors ranging from benign, borderline and malignant. This study aimed to screen differentially expressed microRNAs (miRNAs) between malignant and borderline GISTs and to investigate the potential role of miRNAs in the malignant transformation of GISTs.</p><p><b>METHODS</b>Six GIST samples including borderline tumors (n = 3) and malignant tumors (n = 3) were collected based on the clinical and pathological characteristics. Total RNA was extracted, followed by miRNA microarray analysis to screen the differentially expressed miRNAs. The most significantly expressed 4 miRNAs were then chosen for further validation by real-time PCR in 22 additional GIST samples.</p><p><b>RESULTS</b>Direct comparison of malignant group versus borderline group revealed 14 significantly and differentially expressed miRNAs (P < 0.05, with a fold change of < 0.5 or > 2). Five miRNAs were up-regulated and nine were down-regulated in the malignant group. Four miRNAs (miR-221, miR-135b, miR-675(*) and miR-218) were most significantly and differentially expressed between the two groups. The differential expression of 2 miRNAs (miR-221 and miR-675(*)) were subsequently confirmed with good concordance by real-time PCR.</p><p><b>CONCLUSIONS</b>The differential miRNA expression profiles between two groups are revealed by miRNA microarray assay, and confirmed by real-time PCR. Among differentially expressed miRNAs, miR-221 and miR-675(*) might be related to the malignant transformation of GISTs, and have a potential value in predicting biological behavior of GISTs.</p>

Staging and histologic grading of gastrointestinal stromal tumors / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the clinical stage and histological grade of gastrointestinal stromal tumors.</p><p><b>METHODS</b>Twelve clinical and pathological parameters were assessed in 613 patients with follow-up information. These parameters were classified into two gross spread parameters including liver metastasis and peritoneal dissemination, five microscopic spread parameters including lymph node metastasis, vascular, fat, nerve and mucosal infiltration, and five histological parameters including mitotic count ≥ 10 per 50 high-power fields, muscularis propria infiltration, coagulative necrosis, perivascular pattern and severe nuclear atypia.</p><p><b>RESULTS</b>The accumulated 5-year disease-free survival (DFS) and overall survival (OS) of 293 patients without any of these predictive parameters of malignancy were 99.3% and 100.0%, respectively. They were regarded as nonmalignant and further evaluations on the stage and grade of these tumors were not performed. At least one and at most seven predictive parameters of malignancy were identified in 320 patients. For these patients, the accumulated 5-year DFS and OS rates were 43.9% (mean 6.7 years) and 59.7% (mean 9.3 years), respectively. The DFS showed significant difference between patients with and without gross spread (P < 0.01), with and without microscopic spread (P = 0.001). DFS and OS were associated with the number of predictive parameters of malignancy in patients without gross spread (P < 0.01 for both DFS and OS), but not in patients with gross spread (P = 0.882 and 0.441, respectively).</p><p><b>CONCLUSIONS</b>Malignant GIST could be divided into clinical stages I and II based on the absence and presence of gross spread, respectively. The degree of malignancy of patients in clinical stage I could be graded according to the number of predictive parameters of malignancy. Patients in clinical stage II were of the highest degree of malignancy regardless of the number of parameters. The staging and grading of gastrointestinal stromal tumors in this study are strongly associated with prognosis.</p>

Detection of KRAS gene mutation and its clinical significance in colorectal adenocarcinoma / 中华病理学杂志

<p><b>OBJECTIVE</b>To explore the clinical significance of KRAS mutation detection in colorectal adenocarcinoma.</p><p><b>METHODS</b>Paraffin-embedded tissue specimens were obtained from 440 patients with colorectal adenocarcinoma. The genomic DNA was extracted. Mutations of exon 2 of KRAS gene were examined by PCR and direct sequencing.</p><p><b>RESULTS</b>Somatic mutations of KRAS gene were identified in 146 cases, with the mutation rate of 33.2% (146/440). Among these 146 patients, KRAS mutation involved codon 12 in 118 patients, including 35G > A (Gly12Asp, 62 cases), 35G > T (Gly12Val, 35 cases), 34G > T (Gly12Cys, 9 cases), 34G > A (Gly12Ser, 6 cases), 35G > C (Gly12Ala, 5 cases), and 34G > C (Gly12Arg, 1 case); in 27 patients the mutation involved codon 13, including 38G > A (Gly13Asp, 25 cases), 38G > C (Gly13 Val, 1 case) and 37G > T (Gly13 Cys, 1 case); and in one patient, the mutation involved codon 14 with 40G > A (Val14Ile). The status of KRAS or codon 12 mutations in colorectal adenocarcinoma was related to patients' gender (P = 0.021 and P = 0.030, respectively), and this significant correlation to females was conserved in clinical stage III (P = 0.007 and P = 0.003, respectively), but not in stages I, II, and IV. The status of KRAS or codon 12 mutations was also related to tumor stage. Between stage II and stage IV, the mutation rate of KRAS and codon 12 showed significant difference (P = 0.028 and 0.034, respectively). Between stage III and stage IV, only the codon 12 mutation rate showed significant difference (P = 0.011). Codon 13 mutation was not related to tumor stage.</p><p><b>CONCLUSION</b>About one third of patients with colorectal adenocarcinoma have KRAS gene mutation, which might be related to patients' gender; and could be consistently detected by PCR and direct sequencing.</p>

Focal nodular hyperplasia of liver: a clinicopathologic study of 238 patients / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the clinicopathologic features of focal nodular hyperplasia (FNH) of liver.</p><p><b>METHODS</b>The clinical, radiologic, pathologic findings and follow-up data of 238 cases of FNH were retrospectively analyzed.</p><p><b>RESULTS</b>The patients included 93 females and 145 males. The age of the patients ranged from 11 to 77 years (median = 39.1 years). Amongst the 233 patients who had clinical information available, 188 were asymptomatic, 216 had no history of hepatitis B and/or C infection and 232 had negative serum alpha-fetoprotein level. Amongst the 185 patients who had undergone radiologic examination, 123 (66.5%) were accurately diagnosed as such. Macroscopically, of the 284 lesions from 238 patients, the average diameter was 3.7 cm. Two hundred and fifteen cases (90.3%) were solitary, 172 cases were located in the right lobe and 115(40.5%) had central stellate fibrotic scars or lobulated cut surface. Histologically, 229 lesions belonged to classic type and 9 lesions were of non-classic type. The latter was further classified as the telangiectatic form (6 lesions) and the mixed hyperplastic and adenomatous form (3 lesions). There was no evidence of significant cytologic atypia. Follow-up data were available in 173 patients (72.7%). None of them died of the disease and 2 patients suffered from relapses after 2 and 4 years, respectively.</p><p><b>CONCLUSIONS</b>FNH is a hyperplastic response of normal liver cells to local blood flow anomalies. It has no obvious sex predilection and more than 66% can be diagnosed accurately with radiologic examination. The lesions in the current study show no cytologic atypia.</p>

New prognostic parameters for very-low-risk gastrointestinal stromal tumors / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>According to the National Institutes of Health consensus criteria, gastrointestinal stromal tumors (GISTs) smaller than 2 cm in diameter with less than 5 mitotic figures per 50 high-power fields are considered very-low-risk GISTs, but these two indices alone cannot reliably predict a benign outcome during long-term follow-ups. Therefore, identification of additional parameters for predicting the clinical behavior of GISTs is necessary.</p><p><b>METHODS</b>Eighty-eight patients with tumors that meet the very-low-risk GIST criteria were retrospectively investigated and morphological parameters of tumors associated with the biological behavior of very-low-risk GISTs were evaluated in the present study. The Kaplan-Meier method was used to calculate disease-free survival rates.</p><p><b>RESULTS</b>Eighty-one patients were followed up for one to 16.3 years. Five cases of relapses were identified in the patients. Distinctive infiltrative growth patterns such as muscularis propria, muscularis mucosa, or nerve infiltration were identified by microscopy in 4 patients with the relapse, including three patients who experienced multiple recurrences. The infiltrative growth features became more obvious in multiple recurrent tumors compared to the single recurrent tumor, while only one developed relapse in 76 patients without infiltration (P < 0.0001).</p><p><b>CONCLUSION</b>Microscopic infiltrative growth patterns of the tumor may have clinical significance in predicting the prognosis of very-low-risk GISTs.</p>

Clinicopathological features and prognosis of cystic gastrointestinal stromal tumor / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the clinicopathological and molecular genetic characteristics of gastrointestinal stromal tumor (GISTs) with significant cystic changes, and to assess their biological behavior.</p><p><b>METHODS</b>Clinicopathological features of 7 patients with cystic GISTs treated at the Zhongshan Hospital of Fudan University from February 2005 to January 2010 were summarized retrospectively. The mutations status of c-kit and PDGFR-α were analyzed.</p><p><b>RESULTS</b>There were 2 males and 5 females aged from 46 to 76 years old. Primary site of GISTs included stomach(n=4), duodenum(n=1), and small intestinal(n=2). Tumor size ranged from 6 to 16 cm with obviously cystic changes. Tumor cells were found in the solid components under microscope, of which epithelioid cell type were found in 4 case and spindle cell type in 3 cases. The mitotic figures were no more than 3/50 HPF in all the patients. According to the NIH criteria, 4 were high-risk and 3 were low-risk. Based on morphological characteristics, 3 cases were as borderline tumor, 3 moderate-risk, and 1 moderate-risk. Gene mutation of exon 11 of c-kit were identified in 3 cases. During the follow up ranging from 9 to 80 months, all the 7 patients had cancer-free survival.</p><p><b>CONCLUSION</b>The biological behavior of cystic GIST is indolent with a low risk of malignancy and favorable prognosis.</p>

Role of heterogeneous nuclear ribonucleoprotein A2/B1 protein in the pathogenesis of non-small cell lung cancer / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To study the expression of heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNP A2/B1) in non-small cell lung cancer (NSCLC), and the interaction between hnRNP A2/B1 protein and mRNA of DNA repair enzymes O(6)-methylguanine DNA-methyltransferase (MGMT), 8-oxoguanine DNA glycosylase (OGG1), redox factor 1(Ref-1), DNA-dependent protein kinase (including DNA-PKcs and ku).</p><p><b>METHODS</b>The expression and distribution of hnRNP A2/B1 were detected by immunohistochemistry and Western blot on 50 NSCLC samples from patients who underwent resection in Zhongshan Hospital. The hnRNP A2/B1 mRNA expression was tested by real-time PCR. Co-immunoprecipitation (co-IP) combined RT-PCR was used to investigate whether hnRNP A2/B1 could be bound with the mRNA of the above mentioned 5 DNA repair enzymes in human lung cancer cell line (HTB-182). Then immunohistochemistry and real-time PCR were used to detect the expression of MGMT in the same group of patients.</p><p><b>RESULTS</b>HnRNP A2/B1 protein and mRNA expressions were increased in the NSCLC tissues than that in the corresponding normal lung tissues. HnRNP A2/B1 was expressed predominantly in the nuclei of tumor cells. The positive rate and immunohistochemistry score of hnRNP A2/B1 in tumor tissue were significantly higher than that in normal tissue (P < 0.01). In stage III-IV NSCLC, hnRNP A2/B1 expression was higher than that in stage I-II. There was no significant differences of hnRNP A2/B1 expression among patients of different age, sex, histological type, and smoking history. The results of co-IP combined RT-PCR suggested that hnRNP A2/B1 is bound with MGMT mRNA, and MGMT expression is decreased in tumor tissue of NSCLC.</p><p><b>CONCLUSIONS</b>The results of this study show that hnRNP A2/B1 protein and mRNA are highly expressed in NSCLC, and hnRNP A2/B1 is bound with MGMT mRNA, which indicate that it might be one of the mechanisms of hnRNP A2/B1 participating in the pathogenesis of NSCLC.</p>

Expression of MDR1 and KIT in imatinib-resistant gastrointestinal stromal tumor cells / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To explore the relationship between imatinib resistance and genes MDR1 and KIT in gastrointestinal stromal tumor (GIST) cells.</p><p><b>METHODS</b>The MDR1 and KIT mRNA level in GIST882-R and GIST882-S cells were detected by RT-PCR. Immunocytochemistry and Western blot were employed to detect P-gp and CD117 expression in GIST882-R and GIST882-S cells.</p><p><b>RESULTS</b>The relative expression of MDR1 mRNA was 0.321 + or - 0.033 in GIST882-R and 0.157 + or - 0.056 in GIST882-S cells, and the difference was statistically significant (P<0.05). The relative expression of KIT mRNA was 0.389 + or - 0.063 in GIST882-R and 0.339 + or - 0.067 in GIST882-S, and the difference was not statistically significant (P>0.05). The relative density of P-gp was 0.443 + or - 0.058 in GIST882-R and 0.237 + or - 0.094 in GIST882-S, and the difference was statistically significant (P<0.05). The relative density of CD117 was 0.744 + or - 0.123 in GIST882-R and 0.704 + or - 0.094 in GIST882-S, and the difference was not statistically significant (P>0.05).</p><p><b>CONCLUSIONS</b>Over-expression of gene MDR1 may be associated with imatinib resistance in GIST. KIT may not be involved in imatinib resistance.</p>

Melanotic epithelioid clear cell tumor of kidney: report of three cases / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the pathologic features and immunophenotype of 3 cases of melanotic epithelioid clear cell tumor of kidney.</p><p><b>METHODS</b>More than 2000 cases of renal tumors were retrospectively reviewed. Three cases of melanotic epithelioid clear cell tumor were identified. Immunohistochemical study was carried out using the paraffin-embedded tissue samples. Electron microscopy was also performed in 1 case.</p><p><b>RESULTS</b>Amongst the 3 cases studied, the male-to-female ratio is 1:2. Histologically, 2 cases showed a clear cell carcinoma-like pattern. Papillary structures covered by clear cells and eosinophilic cells were observed in 1 case. Immunohistochemical study showed that the tumor cells in all cases expressed HMB 45. Two of them were also positive for Melan A. The staining for epithelial markers and S-100 protein was negative. Melanosomes were not identified by ultrastructural examination.</p><p><b>CONCLUSIONS</b>Melanotic epithelioid clear cell tumor is a rarely seen neoplasm of kidney. There are some histologic overlaps with renal cell carcinoma, epithelioid angiomyolipoma and melanoma. Immunohistochemical study is useful in confirming the diagnosis. The tumor represents a morphologic variant of epithelioid angiomyolipoma.</p>

Study on clinicopathologic parameters of malignant behavior in gastrointestinal stromal tumors / 中华病理学杂志

<p><b>OBJECTIVE</b>To determinate the clinicopathologic parameters in predicting the malignant behavior of gastrointestinal stromal tumor (GIST).</p><p><b>METHODS</b>Eight hundred and forty cases of GIST were retrospectively reviewed. The tumors were classified as malignant if they met any of the following criteria: evidence of gross dissemination (including liver metastasis and/or peritoneal spread), evidence of microscopic dissemination (including lymph node metastasis, infiltration to vessels, fat tissue, nerves and/or mucosal tissue), or disease relapse. The remaining cases were provisionally classified as tumors of uncertain biologic behavior. A number of morphologic parameters were then evaluated under light microscopy and univariate and multivariate analyses were adopted for this study.</p><p><b>RESULTS</b>Histologic findings correlated with evidences of the following morphologic parameters were considered in accord with the criteria of the malignant behavior: mitotic count>or=10 per 50 high-power fields (P<0.01), muscle infiltration (P<0.01), coagulative necrosis (P<0.01), perivascular growth pattern (P=0.005) and remarkable nuclear atypia (P=0.014). Basing on the above criterion, 485 cases were re-classified as "malignant" and 355 cases "non-malignant". Follow-up data showed that the five-year disease-free survival and overall survival in the "non-malignant" group were 99.3% and 100% respectively, in contrast to 43.9% and 59.7% respectively in the "malignant" group (P<0.01).</p><p><b>CONCLUSIONS</b>The set of clinicopathologic parameters is useful in predicting the malignant behavior of GIST and prognosis.</p>

Clinical and pathological studies of borderline gastrointestinal stromal tumors / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Borderline gastrointestinal stromal tumors (GISTs) are intermediate tumors between benign and malignant variants; however, the clinical and pathological features of borderline GISTs remain poorly defined. This study aimed to characterize GISTs and to identify a set of borderline criteria for practical use.</p><p><b>METHODS</b>Medical records and specimens of 840 patients from 12 hospitals were retrospectively examined. Totally 485 and 76 patients with any of the parameters predictive of either malignant or benign tumors were excluded. The Kaplan-Meier method was used to calculate disease-free survival and overall survival rates.</p><p><b>RESULTS</b>Among the remaining 279 borderline GIST patients, 223 were followed up for 1 to 31.48 years. Two patients developed local recurrence, and both were cured by subsequent operations alone. The 5-year disease-free survival and overall survival rates were 99% and 100%, respectively. Morphologically, borderline GISTs typically exhibited moderate cellularity, and subsets of them also showed moderate atypia, low mitotic activities, or large tumor size. According to the National Institutes of Health (NIH) consensus criteria, the risk levels of the 279 GISTs were classified to be very low to high. However, the disease-free survival rates were not significantly different among these risk groups (P = 0.681).</p><p><b>CONCLUSIONS</b>The proposed borderline GIST criteria in the current study may complement the existing NIH criteria, based primarily on tumor size and mitotic count, in the evaluation of the biological behaviors of GISTs. Since a subset of borderline GISTs with high risk level showed favorable outcome, the introduction of the borderline GIST system may avoid overdiagnosis and over therapy.</p>

Study on the mechanism of imatinib-induced resistance in gastrointestinal stromal tumors / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the mechanism of imatinib mesylate (IM) induced-resistance in the patients with gastrointestinal stromal tumors (GISTs) and treated with imatinib.</p><p><b>METHODS</b>Eight patients with GIST treated with IM developed secondary IM resistance. A total of 16 tumor samples (pre-IM therapy) and 11 tumor samples (post-IM treatment) were available. Exon 9, 11, 13, and 17 of c-kit gene as well as exon 12 and exon 18 of PDGFRA gene were sequenced.</p><p><b>RESULTS</b>In addition to the changes of baseline genotype, the IM-induced gene changes were concentrated in the kinase domain of c-kit gene in all 8 patients, 2 of them were located in the exon 13 of c-kit gene presenting with V654A, while 6 in exon 17 involving 816 and 820 to 823 codons.</p><p><b>CONCLUSION</b>The mechanism of imatinib mesylate resistance after initial treatment with this agent in gastrointestinal stromal tumors is a novel mutation development in kinase domain of c-kit.</p>

Clinical and histopathological alterations of lymphangioleiomyomatosis in 14 Chinese patients / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Lymphangioleiomyomatosis (LAM) is a rare disease that predominantly affects young females. It is considered as an "orphan" life-threatening disease of unknown etiology, with uncertain clinical prognosis, and no effective treatment. LAM can arise sporadically or in association with tuberous sclerosis complex (TSC), an autosomal inherited syndrome characterized by hamartoma-like tumor growth and pathologic features that are distinct from manifestations of pulmonary LAM. The clinical course of LAM is characterized by progressive dyspnea on exertion, recurrent pneumothorax, and chylous fluid collections.</p><p><b>METHODS</b>Fourteen cases of LAM from Zhongshan Hospital, Fudan University are reviewed, twelve were confirmed by lung biopsy, one by retroperitoneal lymphangioleiomyoma resection, and one by autopsy.</p><p><b>RESULTS</b>All 14 patients were women, aged 18 to 69 years (mean 43.3 years, median 46.5 years). Haemoptysis (57.1%) and chylothorax (35.7%) were more frequent than those described in previous case series. Extrapulmonary findings such as renal angiomyolipoma (AML), enlarged abdominal lymph nodes, liver AML and retroperitoneal lymphangioleiomyoma were seen in 21.4%, 14.3%, 7.14% and 7.14% in 14 cases respectively, which is remarkably lower than in the previously reported. Abnormal smooth muscle cells (LAM cells) were found to line the airways, bronchioles, lymphatics and blood vessels leading to airflow obstruction and replacement of the lung parenchyma by cysts. There were some surprises in the autopsy case as several LAM cell emboli were found in the veins of mediastinum lymph nodes; LAM cells were found to be disseminated in soft tissues adjacent to the ilium.</p><p><b>CONCLUSIONS</b>Women with unexplained recurrent pneumothorax, tuberous sclerosis, or a diagnosis of primary spontaneous pneumothorax or emphysema in the setting of limited or absent tobacco use should undergo high-resolution computed tomography (HRCT) scan screening for LAM. Routine abdominal and pelvic imaging examinations should be performed to detect extrapulmonary involvement. The autopsy studies histologically suggested that LAM could be a multisystemic disease and LAM cells might possess metastatic potential.</p>

Detection and clinical significance of plasma vascular endothelial growth factor level in gastrointestinal stromal tumor patients / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the clinical significance of plasma vascular endothelial growth factor (p-VEGF) levels in gastrointestinal stromal tumor (GIST) patients.</p><p><b>METHODS</b>The p-VEGF levels in 61 primary GIST patients, 18 patients with recurrence or metastasis, and 28 healthy blood donators (as control) were measured by enzyme-linked immunosorbent assay. Paired p-VEGF levels of pre- and post-treatment were obtained from 44 patients. One patient received 22 consecutive detections during the follow up.</p><p><b>RESULTS</b>Primary and recurrent GIST patients had higher p-VEGF levels than healthy controls [(145.31+/-45.58) ng/L, (145.72+/-52.73) ng/L vs (89.86+/-18.30) ng/L] (P<0.01). And there were no significant differences between primary patients and patients with recurrence or metastasis (P>0.05). Significant difference were found in the p-VEGF levels between pre- and post-treatment patients (P<0.01). Post-treatment p-VEGF levels decreased markedly both in 26 primary and 11 recurrent patients [(101.81+/-27.63) ng/L and (112.45+/-38.58) ng/L]. As for the patient with 22 consecutive detections during the follow up, p-VEGF levels the period of were higher before surgery and after recurrence, and lower two months after surgery and during Glivec therapy.</p><p><b>CONCLUSIONS</b>The p-VEGF level of GIST patients is significantly higher than that of healthy people, which will decrease markedly after effective management. Monitoring the p-VEGF level in GIST patients will be helpful to evaluate the therapeutic efficacy and predict the recurrence or metastasis.</p>

Clinical characteristics and surgical treatment of 18 cases of duodenal gastrointestinal stromal tumors / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the clinical characteristics, surgical procedures and prognosis of duodenal gastrointestinal stromal tumors (GISTs).</p><p><b>METHODS</b>The clinical data of 18 GIST patients, collected from 1995 to 2004, were retrospectively analyzed.</p><p><b>RESULTS</b>The lesions of duodenal GISTs mainly located in the descending duodenum (13/18), unusually in the horizontal part (2/18), ascending part (1/18), and the bulb (2/18). Pathological examination revealed 1 case of benign tumor, 2 cases of borderline tumors and 15 cases of malignant tumors, Microscopically, the tumors were composed of spindle cells (14 cases), epithelial cell (1 case), and mixed cell types (3 cases). The clinical manifestations were non-specific, mostly was melena (7/18), as well as abdominal pain (6/18), fullness (5/18), and anemia (3/18). The diagnoses were performed by upper gastrointestinal radiography, gastroscopy, endoscopic ultrasonography and CT scan. All of the 18 patients received surgical treatment, including 9 pancreaticoduodenectomies, 5 local resections, 3 segmental resections of duodenum, and 1 distal subtotal gastrectomy. 1 and 3 year survival rates were 100% and 86.7% respectively.</p><p><b>CONCLUSION</b>Most duodenal GISTs are malignant, and the choices of surgical procedures are mainly determined by the location and size of the tumors.</p>