Ai zheng = Aizheng = Chinese journal of cancer最新文献

The incidence and mortality of colorectal cancer (CRC) show increasing tendency worldwide. It was predicted that the new cases in 2007 would be approximate 1,200,000 and the death cases would be 630,000, a total increase of 27% and 28% and an annual increase of 3.9% and 4.0%, respectively, compared with the figures in 2000. In addition, the incidence of CRC varies regionally and changes over the time. In previously identified high-incidence areas, there are three tendencies: one is to keep rising such as in UK, one is to be stable such as in New Zealand, and the third one is to decrease such as in US and Western Europe. In previously identified low-incidence areas, the incidence of CRC is increasing, such as in Japan, Hong Kong, Singapore, Hungary, Poland, Israel, and Puerto-Rico, especially in Japan, where the incidence increases the fastest. Similarly, the incidence of CRC is increased by 4.2% annually in Shanghai, China, which is faster than the average increasing rate of the world. Since 1991, the average increase in mortality of CRC is 4.7% every year. The increasing number of female patients and the shift of the tumor location to the right side are also noticed for CRC in recent years. We summarized that CRC is a disease caused by synergism of environment and diet, life style and heredity. It was suggested that CRC can be prevented effectively through developing a regular life style, having proper diet, actively participating in the screening for cancers, and removing the pre-cancer lesions.

Background and objective: Neoadjuvant therapy (radiotherapy, RT or chemoradiotherapy, CRT) could change status of the invasion and lymph node metastasis of rectal cancer. The risk factors of lymph node metastasis in rectal cancers without neoadjuvant therapy have been well known, but those in rectal cancers treated with preoperative RT or CRT remain unclear. This study was to investigate the risk factors of lymph node metastasis in patients who underwent preoperative RT or CRT for rectal cancers.

Methods: Clinical data of 93 patients underwent preoperative RT or CRT followed by total mesorectal exesion (TME) for locally advanced rectal adenocarcinoma from August, 2003 to February, 2008 were reviewed. Twelve clinicopathologic factors and treatment-related factors were studied with univariate and multivariate analyses.

Results: Univariate analysis showed that post-RT or post-CRT serum carcinoembryonic antigen (CEA) level, radiation dose, time interval from RT or CRT to TME, concurrent chemotherapy with oxaliplatin-containing regimens, and infiltration extent to bowel wall after RT or CRT (ypT stage) were significantly associated with lymph node status after RT or CRT (ypN stage). Multivariate analysis showed that concurrent chemotherapy with oxaliplatin-containing regimens (r=-0.481, P<0.01) and ypT stage (r=0.503, P<0.01) were independent risk factors of ypN stage.

Conclusions: Pathologic T stage is the most reliable predictor of lymph node stage in rectal cancer patients received preoperative RT or CRT. Oxaliplatin-containing regimens could significantly reduce the risks of lymph node metastases and potentially improve the prognosis.

Background and objective: Our previous experiments showed that steep pulses could kill tumor cells, but the mechanism is unclear. This study was to probe the effects of different dosages of energy controllable steep pulses (ECSP) on intracellular concentration of dissociative calcium ion ([Ca2+]i) and cell membrane potential.

Methods: The breast carcinoma MDA-MB-231 cells were divided into control group and five ECSP (different dosages) groups. Ca2+ was labeled by Fluo-3/AM and cell membrane potential was labeled by DiBAC4(3). The mean fluorescence intensity in MDA-MB-231 cells was observed by laser confocal microscopy after ECSP treatment. The changes of calcium concentration and cell membrane potential after ECSP treatment were analyzed. The changes of intracellular [Ca2+]i after ECSP treatment were also observed either with or without Ca2+ outside of the cells.

Results: Ca2+ outflow was observed when the cells were treated with lower dosage of pulse in quiet state; the outflow was enhanced with the dosage increase. In real-time kinetic detection, intracellular Ca2+ concentration was increased with the increase of pulse electric field intensity when cells were treated with lower dosages of ECSP. When the voltage was 285 V, frequency was 100 Hz, [Ca2+]i decreased obviously. The intracellular Ca2+ concentration was obviously lower in the cells without outside Ca2+ than in cells with outside Ca2+, but it still increased gradually. Low dosage of ECSP induced the increase of cell membrane potential, indicating the depolarization of cell membrane. With increase of the dosage, cell membrane potential was attenuated, indicating the superpolarization of cell membrane.

Conclusion: Lower dosage of ECSP can induce the depolarization of cell membrane and the inflow of outside Ca2+; higher dosage of ECSP can directly destroy the cell membrane and induce the superpolarization of cell membrane, then induce the outflow of intracellular Ca2+ which causes the necrosis of tumor cells.

Background and objective: Gastrointestinal stromal tumor (GIST) is one of the most common mesenchymal tumors of the digestive system. Imaging examination plays an important role in preoperative diagnosis and postoperative evaluation for it. This study was to describe the multi-slice spiral computed tomographic (MSCT) findings and pathologic features of GIST, and to analyze their correlation.

Methods: MSCT and pathologic reports of 49 patients with 53 pathologically confirmed GIST lesions were reviewed and compared.

Results: Of the 53 GIST lesions, 14 were at very low biological risk, 11 at low risk, ten at moderate risk and 18 at high risk; 36 (67.9%) were found in first visit by CT scans. On CT images, the GIST lesions with maximal diameter of > or =50 mm showed irregular shape, invasive growth, presence of cystic area and heterogeneous enhancement, and most of them were at high risk; the lesions with maximal diameter of <50 mm showed regular shape, expansive growth, and homogeneous enhancement, and most of them were at risk of moderate or below. No lymph node metastasis was found. Only three lesions showed S100-positive, which presented infiltration along the gastric wall or bowel ring on CT images.

Conclusions: CT examination is helpful in risk prediction for GIST, but it is difficult to detect small lesions (< 2 cm) by CT scans. Due to the infiltrative growth of GIST with neural differentiation (S100-positive), it is difficult to distinguish GIST from gastric cancer on CT images.

Background and objective: Total mesorectal excision (TME) can reduce local recurrence and improve prognosis of rectal cancer. This study was to analyze the clinicopathologic characteristics of rectal cancer, and explore the prognosis factors of rectal cancer after radical TME.

Methods: From 1990 to 2003, 1056 rectal cancer patients had received radical TME. The impacts of 20 clinicopathologic factors on the prognosis were analyzed with univariate and multivariate method.

Results: The 3-, 5-, and 10-year overall survival rates were 84.9% (95% CI, 83.8%-86.0%), 73.8% (95% CI, 72.4%-75.2%), and 65.1% (95% CI, 63.4%-66.8%), respectively. Univariate analysis showed that preoperative serum carcinoembryonic antigen (CEA) and CA19-9 levels, tumor gross type, pathologic type, pathologic grade, preoperative bowel obstruction or bowel perforation, T stage, N stage, and first treatment era were associated with the prognosis of rectal cancer. Multivariate analysis showed that N stage, histological type, surgical procedures, and T stage were independent prognostic factors.

Conclusion: N stage, histological type, surgical procedures, and T stage are independent prognostic factors for rectal cancer patients who received radical TME.

Background and objective: Accurate and early diagnosis of recurrence for cervical cancer after the treatment and aggressive salvage treatment could improve the prognosis of this disease. Serum squamous cell carcinoma antigen (SCCAg) is the most commonly used tumor marker for the detection of asymptomatic recurrence of cervical cancer. This study was to evaluate the application and value of (18)F-FDG PET/CT in cervical cancer with elevated of serum SCCAg level during the follow-up.

Methods: Thirty-one patients with cervical cancer with elevated serum SCCAg level during the follow-up undergoing (18)F-FDG PET/CT in Sun Yat-sen University Cancer Center between August 2005 and November 2008 were entered into this retrospective study. The pathological types, the serum SCCAg level, PET/CT results, results of other imaging modalities, pathological and clinical follow-ups were recorded.

Results: All 31 patients'pathological examination showed squamous cell carcinoma, including three adenosquamous carcinoma. Lesions of all patients were examined by PET/CT. Three patients had local recurrence in the uterus or vagina, 28 had metastatic disease. Of these 31 patients, three were confirmed to have local recurrent disease, 27 were verified to have metastatic disease and one was diagnosed as primary lung squamous cell carcinoma by pathological or clinical manifestations. The total detection rate of PET/CT for malignancy was 100% (31/31); the diagnostic accuracy of PET/CT for recurrent cervical cancer was 96.8% (30/31). The levels of serum SCCAg during the follow-up were 1.5-37.8 ng/ml. There was no relation between the level of serum SCCAg and the maximum standard uptake value (SUVmax) of PET/CT. Compared with other imaging modalities, PET/CT was more efficient in detecting recurrence and finding more lesions.

Conclusions: An elevated level of SCCAg in cervical cancer during the follow-up indicates tumor recurrence. PET/CT is efficient in detecting the recurrence and has high diagnostic accuracy.

Background and objective: Patients with locally advanced rectal cancer undergoing preoperative radiotherapy have disparity in pathological tumor regression. This study was to investigate clinicopathologic factors correlated with pathological complete response (pCR) following preoperative radiotherapy in rectal adenocarcinoma.

Methods: In total 132 patients with rectal adenocarcinoma received preoperative radiation from January 2002 to June 2008 at Sun Yat-sen University Cancer Center. Pathological tumor response after radiation was evaluated, and correlations of pCR to 12 clinicopathologic factors were analyzed using logistic regression method.

Results: A total of 18 patients achieved pCR after preoperative radiation, with a pCR rate of 13.6%. Univariate analysis showed that pretreatment T stage with or without concomitant chemotherapy, pretreatment serum CEA level, and CA199 level were correlated with pCR after preoperative radiation in rectal adenocarcinoma. Multivariate analysis revealed that pretreatment serum CEA level and with or without concomitant chemotherapy were independent factors for pCR after radiotherapy in rectal adenocarcinoma.

Conclusion: Patients undergoing preoperative radiochemotherapy with a low pretreatment serum CEA level were more likely to achieve pCR.

Background and objective: Responses and prognosis vary in patients with colon cancer of the same stage using the same therapeutic strategy. Finding a good marker to predict the prognosis is necessary. This study was to explore the correlations of Survivin and matrix metalloproteinase-7 (MMP-7) expression to the prognosis and clinicopathologic features of colon cancer.

Methods: Clinical data of 620 colon cancer patients, treated in Sun Yat-sen University Cancer Center from January 1995 to May 2003, were analyzed. The expression of Survivin and MMP-7 in the 620 specimens of colon cancer was detected by tissue microarray and immunohistochemistry. Correlations of Survivin and MMP-7 expression to the prognosis and clinicopathologic features were analyzed.

Results: The positive rates of survivin and MMP-7 were significantly higher in colon cancer than in normal colon mucosa (41.0% vs. 0, P<0.001; 88.8% vs. 40.9%, P<0.05). There was no relationship between Survivin expression and patients' age, sex, tumor location, gross and histological type, grade, size of colon cancer. The positive rate of Survivin was significantly higher in advanced colon cancer than in early stage colon cancer (P<0.05). There was no relationship between MMP-7 expression and all clinicopathologic factors of colon cancer. Cox untivariate and multivariate regression analyses showed that survivin and MMP-7 expression were independent factors for prognosis of colon cancer.

Conclusion: MMP-7 and survivin are related to the generation of colon cancer, and are independent factors for prognosis of colon cancer.

The cancer stem cell (CSC) theory stipulates that it is a small population of cells called CSCs that initiates tumor formation and maintains its growth. CSCs are scarce within the bulk of the tumor mass, and possess stem cell-like properties such as self-renewal, differentiation and resistance to therapies, and so on. In the past few years, by using side population technique and approaches based on surface markers, including CD133, CD90, OV6 and EpCAM, researchers have identified and isolated a subpopulation of liver cancer cells with enhanced colony-forming and tumorigenic ability, which is strong evidence for the existence of liver CSCs. In this review, we summarized the progress of research on liver CSCs, discussed the significance of liver CSCs in the diagnosis and treatment of hepatocellular carcinomas, and put forward the future research directions as well as the challenges and opportunities.

Background & objective: During the helical tomotherapy process, megavoltage computed tomography (MVCT) images are usually used for guiding the precise setup of patients before/after treatment delivery, which would certainly increase the total dose for patients. This study was to investigate the imaging dose of MVCT using the body and head phantom on a tomotherapy machine.

Methods: A set of cylindrical body and head phantoms was adopted for scanning with different pitch values (1.0/2.0/3.0), lengths (4.8/7.2/9.6/12/14.4 cm) and patient setups on the couch of tomotherapy system. The average MVCT imaging doses were measured using A1SL chambers inserted in the phantoms with preset geometry. The dose uniformity was qualitatively analyzed.

Results: The MVCT scanning dose for the body phantom was between 0.599 and 2.876 cGy during each treatment delivery, while the dose for the head phantom was between 0.913 and 3.231 cGy. Two major parameters, the assigned pitch numbers and scanning lengths, were the most important impacts to the dose variation. The MVCT dose was inversely proportional to the CT pitch value. With respect to the scanning length, the doses responded differently along the radial direction of the phantoms with different setup criteria.

Conclusion: The results may provide a reliable guidance for proper planning design of the scanning region, which is valuable to help minimize the extra doses to patient.