Home About us Editorial board Search Ahead of print Current issue Archives Submit article Instructions Subscribe Contacts Login 


 
 Table of Contents  
ORIGINAL ARTICLE
Year : 2021  |  Volume : 34  |  Issue : 4  |  Page : 1451-1456

Correlation between circulating tumor cells and ovarian tumors' histopathology


1 Department of Obstetrics and Gynecology, Faculty of Medicine, Menoufia University, Menoufia, Egypt
2 Department of Immunology and Zoology, Faculty of Science, Tanta University, Tanta, Egypt
3 Department of Obstetrics and Gynecology, Shebin El Koom Teaching Hospital, Menoufia, Egypt

Date of Submission19-Apr-2021
Date of Decision04-Jun-2021
Date of Acceptance07-Jun-2021
Date of Web Publication24-Dec-2021

Correspondence Address:
Mohammed H Sheleby
MSC, Shebin El Koom, Menoufia
Egypt
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/mmj.mmj_88_21

Rights and Permissions
  Abstract 


Objective
To determine the correlation between the ovarian masses' histopathology and circulating tumor cells (CTCs).
Background
Ovarian cancer is the most frequent cause of death among gynecological cancer cases worldwide.
Patients and methods
This is a prospective study that was carried on 66 patients in Obstetrics and Gynecology Department, Faculty of Medicine, Menoufia University and Centre of Excellence in Cancer Research between December 2018 and March 2021. The patients included in the study were with a previous diagnosis of suspected ovarian malignancy depending on history, ultrasound criteria, and tumor markers and prepared for exploratory laparotomy for debulking surgery. For all patients, detailed history taking, complete clinical examination, abdomen and pelvic ultrasound, cancer antigen 125 and risk of malignancy index (RMI) were done.
Results
Our results reported that there was a highly statistically significant positive correlation between CTCs and RMI in the studied patients and a highly statistically significant positive correlation between CTCs and cancer antigen 125 in the studied patients. There was a highly statistically significant positive correlation between CTCs and International Federation of Gynaecology and Obstetrics (FIGO) staging in the studied patients; however, no statistically significant correlation between RMI and FIGO staging was found in the studied patients. There was a statistically significant difference (P < 0.05) between the studied cases (CTCs) regarding histopathological grades.
Conclusion
CTCs allow differentiation between malignant and nonmalignant ovarian masses, and CTCs are well correlated with the FIGO stage.

Keywords: histopathology, ovarian tumors, tumor cells


How to cite this article:
Gad MS, Salem ML, Alhalaby AE, Sheleby MH. Correlation between circulating tumor cells and ovarian tumors' histopathology. Menoufia Med J 2021;34:1451-6

How to cite this URL:
Gad MS, Salem ML, Alhalaby AE, Sheleby MH. Correlation between circulating tumor cells and ovarian tumors' histopathology. Menoufia Med J [serial online] 2021 [cited 2024 Mar 29];34:1451-6. Available from: http://www.mmj.eg.net/text.asp?2021/34/4/1451/333267




  Introduction Top


Ovarian cancer is the most frequent cause of death among gynecological cancers worldwide. Most cases are diagnosed in the late stage of the disease, which results in poor survival [1]. The 5-year survival rate of patients with ovarian cancer is only around 30% in the late stage [2]. The reason for delayed diagnosis is partly owing to lack of sensitive signs, symptoms, and effective screening methods. Although survival has been improved with the use of cytoreduction surgery along with platinum and/or taxane-based chemotherapy, nearly 80% eventually relapse within 5 years [3]. Therefore, methods that help detection of ovarian cancer in the early stage and monitoring of tumor progression have great potential to improve survival of the patients. It was considered that ovarian cancer spread primarily through direct dissemination in the abdominal cavity. Nevertheless, the presence of disseminated tumor cells (DTCs) in bone marrow of patients with ovarian cancer has been reported [4]. However, bone marrow sampling is rather an invasive procedure, which is not widely accepted in the clinical management. In recent years, focus has been shifted to the detection of circulating tumor cells (CTCs) in the peripheral blood. CTCs are tumor cells released from primary tumor and then circulate through the blood stream, resulting in spreading to different organs and subsequent outgrowth of the tumor cells in the new microenvironment. These CTCs thereby have the potential to contribute to the development of local and systemic relapses [5]. Either DTCs or CTCs have potential to predict prognosis and to monitor treatment efficacy in patients with cancer. The presence of CTCs has been reported in several solid tumors, including breast [6], colorectal [7], lung [8], kidney [9], esophageal [10], liver [11], and prostate [12]. Studies of CTCs/DTCs in patients with ovarian cancer have been investigated, and most of them demonstrate that CTCs and DTCs are associated with poor clinical outcome [13].

However, other studies failed to show the positive correlation and even demonstrated a negative correlation between CTCs/DTCs and progression-free survival, disease-free survival, and overall survival [14]. Guo et al. [15] evaluated the role of CTCs in ovarian tumors and found that CTCs are a useful diagnostic indictor of ovarian cancer.

Our study was established to determine the correlation between the ovarian masses' histopathology and CTCs.


  Patients and methods Top


Study design: this was a prospective study.

Study setting: this study was carried on 66 patients in Obstetrics and Gynecology Department, Faculty of Medicine, Menoufia University and Centre of Excellence in Cancer Research between December 2018 and March 2021.

Sample size calculation

The sample size was calculated by using the following formula:



Z: a percentile of slandered normal distribution determined by 95% confidence level = 1.96.

Δ: the width of the confidence interval = 12.

P: the prevalence of disease = 20%.

N=(1.96/12)2 × 20 (100–20)=43 patients.

All cases included in the study had risk of malignancy index (RMI) more than 25, and in them, the risk of malignancy is 20% [15].

Ethical consideration

Ethical Scientific Committee of Menoufia University approved the study protocol, and an informed consent was taken from the patients before their enrollment in the study.

Study population: the patients who had fulfilled the inclusion criteria, with a history of suspected ovarian malignancy depending on history, ultrasound criteria, and tumor markers and were prepared for exploratory laparotomy for debulking surgery were included.

All patients were subjected to the following:

  1. Full history taking.
  2. Clinical examination.
  3. Abdomen and pelvic ultrasound.
  4. Tumor markers according to the need, but cancer antigen 125 (CA125) was done for all cases.
  5. Routine preoperative investigations.
  6. RMI was calculated by CA125×US index×menopausal index (NICE, 2011).


US index:

  1. If no criteria of malignancy.
  2. If one criteria of malignancy.
  3. If two or more criteria of malignancy.


Menopausal index:

  1. If premenopausal.
  2. If postmenopausal.


Exclusion criteria:

The following were the exclusion criteria:

  1. Received chemotherapy.
  2. Pregnant.
  3. History of previous malignant tumor.


Methodology

Two milliliters of peripheral blood was collected in an EDTA tube from all patients. Then, 100 μl of blood was stained with anti-human mAbs using concentrations recommended by the manufacturers of each antibody. The stained samples were incubated in dark at 4°C for 20–30 min, and then BD FACS lysing solution (1×) was added for 15 min for red blood cell (RBCs) lysis. Samples were then centrifuged at 1250 rpm for 5 min, and then the supernatant was discarded to remove the lysed RBCs. Cells were washed twice using phosphate buffer saline to remove any remaining debris or RBCs, and then the cells were suspended in phosphate buffer saline. Negative stained samples were used as internal controls all over the experiments. FACSCanto II (BD Biosciences, Franklin Lakes, New Jersey , USA) was used for acquisition. FACSDiva (BD Biosciences) software and/or Flowjo software (FlowJo LLC, 385 Williamson Way Ashland, OR 97520 USA) were used for data analysis.

CTCs were characterized by using BD FACSCanto II, and the percentage of CTC was determined by the following phenotype: CD 105 positive, CD24 positive, CD117 negative, and Epcam negative.

The ovarian masses were sent for histopathology, and surgical staging for malignant tumors were done according to International Federation of Gynaecology and Obstetrics (FIGO) staging 2013.

Statistical analysis

Data were analyzed using Statistical Program for Social Science (SPSS Inc., Chicago, Illinois, USA), version 24. Quantitative data were expressed as mean ± SD. Qualitative data were expressed as frequency and percentage. Mean (average) is the central value of a discrete set of numbers, specifically the sum of values divided by the number of values. SD is the measure of dispersion of a set of values. A low SD indicates that the values tend to be close to the mean of the set, whereas a high SD indicates that the values are spread out over a wider range. A one-way analysis of variance was used when comparing between more than two means. Pearson's correlation coefficient (r) test was used for correlating data.

P value less than 0.05 was considered significant.


  Results Top


Clinical data in all studied patients were as follows: regarding age, the mean age in all studied patients was 50.6 ± 16.6 years with minimum age of 20 years and maximum age of 77 years. Regarding BMI, the mean BMI in all studied patients was 29.4 ± 4.1 kg/m2, with minimum BMI of 20 kg/m2 and maximum BMI of 38 kg/m2. Regarding parity, nine (13.6%) patients were para 1, nine (13.6%) patients were para 2, 21 (31.8%) patients were para 3, nine (13.6%) patients were para 4, nine (13.6%) patients were para 5, three (4.5%) patients were para 6, three (4.5%) patients were para 7, and three (4.5%) patients were para 8. Regarding the menopausal state, 33 (50%) patients were premenopausal and 33 (50%) patients were postmenopausal. Regarding symptoms, 36 (54.5%) patients were symptomatic and 30 (45.5%) patients were asymptomatic.

In our study, the histopathological data in all studied patients were as follows: 33 (50%) patients were epithelial ovarian cancer, six (9.1%) patients were malignant germ cell tumor, six (9.1%) patients were malignant sex cord stromal, six (9.1%) were secondary malignancy to ovary, nine (13.6) patients were benign, and six (9.1%) patients were borderline. Regarding grading, 18 (35.3%) patients were grade I, six (11.8%) patients were grade II, and 27 (52.9%) patients were grade III. Regarding lymph nodes, it was negative in 30 (45.5%) patients, undetermined in 33 (50%) patients, and positive in three (4.5%) patients. The mean CTC in all the studied patients was 0.63 ± 0.8 cell/μl, with minimum CTC of 0 cell/μl and maximum CTC of 2.7 cell/μl [Table 1].
Table 1: Histopathological data, histopathological grade, and lymph node histopathology in all studied patients

Click here to view


Description of CTC, RMI, and CA125 regarding histopathological results shows that regarding CTC, in malignant patients, the mean CTC was 0.93 ± 0.83 cell/μl with minimum CTC of 0.2 cell/μl and maximum CTC of 2.7 cell/μl in primary ovarian malignancy, and no CTCs were found in secondary ovarian malignancy, benign, or borderline ovarian tumor. Regarding RMI, in benign patients, the mean RMI was 35.5 ± 4.48 with minimum RMI 30 and maximum RMI 45. In borderline patients, the mean RMI was 40 ± 10.9, with minimum RMI of 30 and maximum RMI of 50. In patients with primary ovarian cancer, the mean RMI was 3643.6 ± 4137.1 with minimum RMI of 25 and maximum RMI of 11 700. In patients with secondary ovarian cancer, the mean RMI was 1088.5 ± 472.7 with minimum RMI of 657 and maximum RMI of 1520. Regarding CA125, in benign patients, the mean CA125 was 21.7 ± 6.6 U/ml, with minimum CA125 of 15 U/ml and maximum CA125 of 30 U/ml. In borderline patients, the mean CA125 was 40 ± 10.9 U/ml, with minimum CA125 of 30 U/ml and maximum CA125 of 50 U/ml. In patients with primary ovarian cancer, the mean CA125 was 545.3 ± 616.2 U/ml with minimum CA125 of 23 U/ml and maximum CA125 of 1300 U/ml. In patients with secondary ovarian, the mean CA125 was 416.5 ± 376.3 U/ml, with minimum CA125 of 73 U/ml and maximum CA125 of 760 U/ml [Table 2].
Table 2: Circulating tumor cell, risk of malignancy index and cancer antigen 125 regarding histopathological results

Click here to view


Our results showed that there were highly statistically significant (P < 0.001) positive correlations (r = 0.53) between CTCs and RMI in the studied patients and a highly statistically significant (P < 0.001) positive correlation (r = 0.42) between CTCs and CA125 in the studied patients [Table 3].
Table 3: Pearson correlation between circulating tumor cells and cancer antigen 125 and risk of malignancy index

Click here to view


Pearson correlation between FIGO stage and CTCs and RMI demonstrated that there is a highly statistically significant (P < 0.001) positive correlation (r = 0.55) between CTCs and FIGO staging in the studied patients, and there is no statistically significant (P = 0.083) correlation (r = 0.24) between RMI and FIGO staging in the studied patients [Table 4].
Table 4: Pearson correlation between International Federation of Gynaecology and Obstetrics stage and circulating tumor cell and risk of malignancy index

Click here to view


Our results also showed a statistically significant difference (P < 0.05) between the studied cases' histopathological grades and CTCs [Table 5].
Table 5: Correlation study between circulating tumor cell and grade in the studied patients

Click here to view


Our results show a highly significant difference (P < 0.001) between the studied cases' lymph nodes state and CTCs [Figure 1]
Figure 1: Correlation study between CTC and LN in the studied patients. CTC, circulating tumor cell; LN, lymph node.

Click here to view



  Discussion Top


Ovarian cancer is thought to spread via direct spread; therefore, CTC detection is not useful for early detection. A recent study based on the parabiosis model in which paired mice shared blood not lymphatic vessels highlighted hematogenous metastasis as an important mode of ovarian cancer metastasis [16]. Regarding the histopathological data in all studied patients, 33 (50%) patients had epithelial ovarian cancer, six (9.1%) patients had malignant germ cell tumor, six (9.1%) patients had malignant sex cord stromal, six (9.1%) had secondary malignancy to ovary, nine (13.6) patients had benign, and six (9.1%) patients had borderline. These results are in agreement with the results of Yaqoob et al. [17], which found that in Egypt, ECO is the most common histopathological type of primary malignant ovarian neoplasms (represents 82.61%).

Regarding grading, our study demonstrates that 18 (35.3%) patients were grade I, six (11.8%) patients were grade II, and 27 (52.9%) patients were grade III. Regarding lymph nodes, it was negative in 30 (45.5%) patients, undetermined in 33 (50%) patients, and positive in three (4.5%) patients. The mean CTCs in all the studied patients was 0.63 ± 0.8 cell/μl, with minimum CTCs of 0 cell/μl and maximum CTCs of 2.7 cell/μl. However, in patients with primary malignancy, the mean CTCs was 0.93 ± 0.83 cell/μl with minimum CTCs of 0.2 cell/μl and maximum CTCs of 2.7 cell/μl. In 51 patients with cancer, 45 patients had primary ovarian cancer and six patients had secondary ovarian cancer. CTCs were found in 100% of the patients with primary ovarian cancer, and no CTCs were found in patients with secondary ovarian cancer. Moreover, no CTCs were found in patients with benign or borderline ovarian tumor.

These results are in agreement with the results of Wei et al. [18], which found CTCs in 18 of 20 patients with ovarian cancer, the mean number of CTCs was 0.2 cell/μl and maximum 3.1 cells/μl using tumor specific fluorescent ligands to label CTCs and use flow cytometry to count the CTCs.

Zhang et al. [19] used PCR to detect CTCs in patients with ovarian cancer and found the average number of CTCs in 98 of 109 patients with ovarian cancer was 264 (range, 0–1929) per 5 ml.

Lou et al. [20] using Cell Search method to detect CTCs in patients with ovarian masses found that no CTCs were found in these with benign disease (14 patients), present in 17% (5/29) of patients with ovarian cancer, and present in 80% (4/5) of patients with secondary ovarian cancer, which disagree with our results, in which no CTCs were detected in patients with secondary ovarian cancer.

Our results demonstrated that mean RMI was 35.5 ± 4.48, with minimum RMI of 30 and maximum RMI of 45, in benign patients. In borderline patients, the mean RMI was 40 ± 10.9, with minimum RMI of 30 and maximum RMI of 50. In primary ovarian patients, the mean RMI was 3643.6 ± 4137.1, with minimum RMI of 25 and maximum RMI of 11 700. In patients with secondary ovarian cancer, the mean RMI was 1088.5 ± 472.7, with minimum RMI of 657 and maximum RMI of 1520. These results are in agreement with the National Institute for Health and Care Excellence (NICE) guideline on ovarian cancer, which recommends that people with an RMI score of 250 or more should be referred to a specialist MDT [21],[22].

Regarding CA125, in benign patients, the mean CA125 was 21.7 ± 6.6 U/ml, with minimum CA125 of 15 U/ml and maximum CA125 of 30 U/ml. In borderline patients, the mean CA125 was 40 ± 10.9 U/ml, with minimum CA125 of 30 U/ml and maximum CA125 of 50 U/ml. In patients with primary ovarian cancer, the mean CA125 was 545.3 ± 616.2 U/ml, with minimum CA125 of 23 U/ml and maximum CA125 of 1300 U/ml. In patients with secondary ovarian cancer, the mean CA125 was 416.5 ± 376.3 U/ml with minimum CA125 of 73 U/ml and maximum CA125 of 760 U/ml. Moreover, this agrees with the NICE guidelines, which recommend testing of serum CA125 for postmenopusal women presenting with vague abdominal symptoms suggestive of EOC for more than 2 weeks and referral for US if CA125 of more than 35 IU/ml to calculate RMI [21],[22].

Our study showed a highly statistically significant (P < 0.001) positive correlation (r = 0.53) between CTCs and RMI in the studied patients and a highly statistically significant (P < 0.001) positive correlation (r = 0.42) between CTCs and CA125 in the studied patients. Contradictory results were presented by Zhang et al. [19], which found no correlation between CA125 and CTCs.

In the preset study, there was a highly statistically significant (P < 0.001) positive correlation (r = 0.55) between CTCs and FIGO staging in the studied patients, whereas no statistically significant (P = 0.083) positive correlation (r = 0.24) between RMI and FIGO staging was found. These results agree with the results of Lou et al. [20] and Zhang et al. [19].

Our study reported a statistically significant relation (P < 0.05) between tumor grade and CTCs. Contradictory results were presented by Lou et al. [20] and Zhang et al. [19], which failed to find a significant relationship between histopathological grade and CTCs.

Our results reported that there were highly statistically significant difference (P < 0.001) between lymph node metastasis and CTCs. This disagrees with the results of Lou et al. [20] and Zhang et al. [19], which found no statistically significant relation between CTC and lymph nodes, despite a statistically significant relation between CTC and FIGO stage found by both studies.


  Conclusion Top


  1. CTCs allow differentiation between malignant and nonmalignant ovarian masses.
  2. CTCs are well correlated with FIGO stage.
  3. CTCs are absent in benign and borderline ovarian tumors.
  4. CTCs are correlated with ovarian cancer grade and lymph nodes' histopathology.


Recommendation

We recommend using CTCs in the diagnosis of suspected ovarian masses, as it differentiates between malignant and nonmalignant ovarian masses and allows prediction of FIGO stage, thereby helps in accurate prediction of prognosis.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

1.
Jemal A, Siegel R, Ward E, Hao Y, Xu J, Thun MJ. Cancer statistics, 2009. CA Cancer J Clin 2009; 59:225–249.  Back to cited text no. 1
    
2.
Baldwin LA, Huang B, Miller RW, Tucker T, Goodrich ST, Podzielinski I, et al. Ten-year relative survival for epithelial ovarian cancer. Obstetr Gynecol 2012; 120:612–618.  Back to cited text no. 2
    
3.
Yap TA, Carden CP, Kaye SB. Beyond chemotherapy: targeted therapies in ovarian cancer. Nat Rev Cancer 2009; 9:167–181.  Back to cited text no. 3
    
4.
Wimberger P, Heubner M, Otterbach F, Fehm T, Kimmig R, Kasimir-Bauer S. Influence of platinum-based chemotherapy on disseminated tumor cells in blood and bone marrow of patients with ovarian cancer. Gynecol Oncol 2007; 107:331–338.  Back to cited text no. 4
    
5.
Chen XL, Ding J. Individualized cancer chemotherapy integrating drug sensitivity tests, pathological profile analysis and computational coordination – an effective strategy to improve clinical treatment. Med Hypotheses 2006; 66:45–51.  Back to cited text no. 5
    
6.
Aceto N, Bardia A, Miyamoto DT, Donaldson MC, Wittner BS, Spencer JA, et al. Circulating tumor cell clusters are oligoclonal precursors of breast cancer metastasis. Cell 2014; 158:1110–1122.  Back to cited text no. 6
    
7.
Lim SH, Becker TM, Chua W, Caixeiro NJ, Ng WL, Kienzle N, et al. Circulating tumour cells and circulating free nucleic acid as prognostic and predictive biomarkers in colorectal cancer. Cancer Lett 2014; 346:24–33.  Back to cited text no. 7
    
8.
Turner AM, McGowan L, Millen A, Rajesh P, Webster C, Langman G, et al. Circulating DBP level and prognosis in operated lung cancer: an exploration of pathophysiology. Eur Respir J 2013; 41:410–416.  Back to cited text no. 8
    
9.
Kolostova K, Cegan M, Bobek V. Circulating tumour cells in patients with urothelial tumours: enrichment and in vitro culture. Can Urol Assoc J 2014; 8:E715–E720.  Back to cited text no. 9
    
10.
Driemel C, Kremling H, Schumacher S, Will D, Wolters J, Lindenlauf N, et al. Context-dependent adaption of EpCAM expression in early systemic esophageal cancer. Oncogene 2014; 33:4904–4915.  Back to cited text no. 10
    
11.
Morris KL, Tugwood JD, Khoja L, Lancashire M, Sloane R, Burt D, et al. Circulating biomarkers in hepatocellular carcinoma. Cancer Chemother Pharmacol 2014; 74:323–332.  Back to cited text no. 11
    
12.
Medina-Villaamil V, Martínez-Breijo S, Portela-Pereira P, Quindós-Varela M, Santamarina-Cainzos I, Antón-Aparicio LM, et al. Circulating MicroRNAs in blood of patients with prostate cancer. Acta Urol Esp 2014; 38:633–639.  Back to cited text no. 12
    
13.
Sang M, Wu X, Fan X, Sang M, Zhou X, Zhou N. Multiple MAGE-A genes as surveillance marker for the detection of circulating tumor cells in patients with ovarian cancer. Biomarkers 2014; 19:34–42.  Back to cited text no. 13
    
14.
Aktas B, Kasimir-Bauer S, Heubner M, Kimmig R, Wimberger P. Molecular profiling and prognostic relevance of circulating tumor cells in the blood of ovarian cancer patients at primary diagnosis and after platinum-based chemotherapy. Int J Gynecol Cancer 2011; 21:5.  Back to cited text no. 14
    
15.
Guo YX, Neoh KH, Chang XH, Sun Y, Cheng HY, Ye X, et al. Diagnostic value of HE4+circulating tumor cells in patients with suspicious ovarian cancer. Oncotarget 2018; 9:7522–7533.  Back to cited text no. 15
    
16.
Pradeep S, Kim SW, Wu SY, Nishimura M, Chaluvally-Raghavan P, Miyake T, et al. Hematogenous metastasis of ovarian cancer: rethinking mode of spread. Cancer Cell 2014; 26:77–91.  Back to cited text no. 16
    
17.
Yaqoob I, Hashem IA, Gani A, Mokhtar S, Ahmed E, Anuar NB, et al. Big data: from beginning to future. Int J Inform Manage 2016; 36:1231–1247.  Back to cited text no. 17
    
18.
Wei JJ, William J, Bulun S. Endometriosis and ovarian cancer: a review of clinical, pathologic, and molecular aspects. Int J Gynecol Pathol 2011; 30:553.  Back to cited text no. 18
    
19.
Zhang X, Li H, Yu X, Li S, Lei Z, Li C, et al. Analysis of circulating tumor cells in ovarian cancer and their clinical value as a biomarker. Cell Physiol Biochem 2018; 48:1983–1994.  Back to cited text no. 19
    
20.
Lou E, Vogel RI, Teoh D, Hoostal S, Grad A, Gerber M, et al. Assessment of circulating tumor cells as a predictive biomarker of histology in women with suspected ovarian cancer. Lab Med 2018; 49:134–139.  Back to cited text no. 20
    
21.
National Institute for Health and Care Excellence (NICE). Ovarian cancer: recognition and initial management. Clinical guideline [CG122]. Available from:. https://www.nice.org.uk/guidance/cg122. [Last accessed on 2019 May 15].  Back to cited text no. 21
    
22.
Redman C, Duffy S, Bromham N, Francis K. Recognition and initial management of ovarian cancer: summary of NICE guidance. BMJ 2011; 2011:342.  Back to cited text no. 22
    


    Figures

  [Figure 1]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5]



 

Top
 
 
  Search
 
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

 
  In this article
Abstract
Introduction
Patients and methods
Results
Discussion
Conclusion
References
Article Figures
Article Tables

 Article Access Statistics
    Viewed482    
    Printed22    
    Emailed0    
    PDF Downloaded64    
    Comments [Add]    

Recommend this journal


[TAG2]
[TAG3]
[TAG4]