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2013, Volume 29, Number 1, Page(s) 027-035
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DOI: 10.5146/tjpath.2013.01144
The Prognostic Value of Tumor-Stroma Proportion in Laryngeal Squamous Cell Carcinoma
Mehtat ÜNLÜ1, Hasan Oğuz ÇETİNAYAK2, Devrim ÖNDER3, Cenk ECEVİT4, Fadime AKMAN2, Ahmet Ömer İKİZ4, Emel ADA5, Bilge KARAÇALI3, Sülen SARIOĞLU1
1Department of Pathology, Dokuz Eylül University, Faculty of Medicine, İZMİR, TURKEY
2Department of Radiation Oncology, Dokuz Eylül University, Faculty of Medicine, İZMİR, TURKEY
3Department of Electrical and Electronics Engineering, Institute of Technology, İZMİR, TURKEY
4Department of Otorhinolaryngology, Dokuz Eylül University, Faculty of Medicine, İZMİR, TURKEY
5Department of Radiology, Dokuz Eylül University, Faculty of Medicine, İZMİR, TURKEY
Keywords: Laryngeal neoplasms, Prognosis, Stromal cell, Tumor
Abstract
Objective: Tumor-stroma proportion of tumor has been presented as a prognostic factor in some types of adenocarcinomas, but there is no information about squamous cell carcinomas and laryngeal carcinomas.

Material and Method: Five digital images of the tumor sections were obtained from 85 laryngeal carcinomas. Proportion of epithelial tumor component and stroma were measured by a software tool, allowing the pathologists to mark 205.6 μm2 blocks on areas as carcinomatous/stromal, by clicking at the image. Totally, 3.451 mm2 tumor areas have been marked to 16.785 small square blocks for each case.

Results: Median follow up was 48 months (range 3-194). The mean tumor-stroma proportion was 48.63+18.18. There was no difference for tumor-stroma proportion when tumor location, grade, stage and perinodal invasion were considered. Although the following results were statistically insignificant, the mean tumor-stroma proportion was the lowest (37.46±12.49) for subglottic carcinomas, and it was 52.41±37.47, 50.86+19.84 and 44.56±16.91 for supraglottic, transglottic and glottic cases. The tumor-stroma proportion was lowest in cases with perinodal invasion and the highest in cases without lymph node metastasis (44.72±20.23, 47.77±17.37, 50.05±17.34). Tumor-stroma proportion was higher in the basaloid subtype compared with the classical squamous cell carcinoma (53.76±14.70 and 48.63±18.38 respectively). The overall and disease-free survival analysis did not reveal significance for tumor-stroma proportion (p=0.08, p=0.38). Only pathological stage was an independent factor for overall survival (p=0.008).

Conclusion: This is the first series investigating tumor-stroma proportion as a prognostic marker in laryngeal carcinomas proposing a new method, but the findings do not support tumor-stroma proportion as a prognostic marker.

Introduction
All malignant epithelial tumors composed of epithelial cells are admixed with supportive tissue, named as “stroma” and this special tissue includes vascular-lymphatic channels and inflammatory cells as well as some type of fibrous tissue, so called desmoplasia. Desmoplastic stroma is composed of activated fibroblast-like cells and new extracellular matrix, induced by invasion of malignant cells1,2 and today, it is known that the tumor stroma has an important role in tumor progression, invasion and metastasis1,3,4. Tumor-stroma ratio or tumor-stroma proportion (TSP) has been presented as a prognostic factor in some types of carcinomas, including prostate, colorectal, esophageal and breast adenocarcinomas5-11. Additionally, desmoplasia is presented as a poor prognostic factor in colon and lung adenocarcinoma12-14 and in squamous cell carcinomas (SCC) of the skin and the desmoplastic variant of skin SCC is known as a very aggressive tumor15-18. There is no information about TSP of SCC and laryngeal carcinomas, in particular.

Among all cancers, carcinoma of the larynx accounts for 2.2% in men and 0.4% in women, with an increase at the latter group, probably due to changing habits of smoking19. Most of the laryngeal carcinomas originate from the supraglottic and glottic region. Although glottic carcinomas frequently remain localized for a long time, supraglottic and subglottic carcinomas tend to spread into the pre-epiglottic region and pyriform sinus as well as base of the tongue and subglottic SCC may spread to the thyroid gland, hypopharynx, esophagus and tracheal wall. Many unfavorable prognostic factors are defined for laryngeal carcinomas, including advanced stage, subglottic localization, high microscopic grade, high number and size of involved lymph nodes, and presence of extranodal extension, epidermal growth factor receptor expression, tumor budding and DNA aneuploidy20-25. In this study the prognostic value of TSP is investigated in laryngeal SCC for the first time, in a series of patients treated with surgery and radiotherapy.

  • Top
  • Abstract
  • Introduction
  • Methods
  • Results
  • Disscussion
  • References
  • Methods
    Eighty-five patients with laryngeal carcinoma who were evaluated in this study were all diagnosed and treated at Dokuz Eylül University Hospital and had complete followup information. Patients were treated by partial or total laryngectomy and neck dissection, followed by adjuvant radiotherapy and close/involved margins or neck involved with multiple nodes or perinodal invasion patients received concomitant cisplatin-based chemotherapy.

    Age, gender, tumor location, clinical tumor stage and lymph node stage, type of surgery, pathological tumor and lymph node stage and the number of metastatic lymph nodes, perinodal invasion, tumor grade, treatment scheme with radio/chemotherapy time and localization of loco/regional recurrence and distant metastasis were determined from the medical records of the patients. Second primary tumors, time of disease-related and all-cause death, and the date of the last follow-up time were recorded.

    Histopathological evaluation
    Hematoxylin and eosin (H&E) stained sections of the patients with SCC were re-evaluated and 5 digital images were taken from adjacent tumor areas including deepest invasive margin, from the regions with most abundant stromal component, for each case by a 3-CCD color video camera (Olympus DP70, Olympus Optical Co. Ltd., Tokyo, Japan), connected to a light microscope (Olympus BX51, Olympus Optical Co. Ltd., Tokyo, Japan) at an original magnification of x20 and they were stored at a personal computer, only excluding large necrotic regions.

    Image Analysis
    TSP was measured at the images mentioned above by a novel software tool developed in C++ with a Graphical User Interface for the Windows operating system Histopathological Image Atlas Editor (HIAE), allowing the pathologists to mark square blocks of the target area in two types by left or right clicking by mouse and automatically calculating the proportion of the marked areas. The two types were tumor or stroma in this study. The area of square regions, delineated by the software program automatically, which could be marked by the pathologist, was 205.6 μm2. The final result for each case was calculated by the mean of the TSP’s of five images which were obtained by examining a 3.451 mm2 area which corresponds to 16.785 square blocks in total. The selection of each case took about fifteen minutes. A screen snapshot of the HIAE is presented in Figure 1. In this figure, the main window of the HIAE displaying a histopathology slide under examination is presented. Individual square regions that were marked by the expert were merged and framed onto the image and also the coverage percentage of the markings was presented by a pie chart. In this case, the areas selected as red are the tumor and the yellow are stromal components.


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    Figure 1: An image sample of selected tumor area with the software Histopathological Image Atlas Editor.

    Statistical analysis
    The cases were grouped by TSP as low and high according to the mean of the TSP values of all the cases. Statistical analysis was conducted by Scientific Package for Social Sciences (SPSS 11). For comparison of these groups, nonparametric tests such as chi-Square were applied. The overall and disease free survival analysis was plotted by the Kaplan Meier method. For comparison of the survival of different groups, the log rank test was applied for unvaried analysis with 95% confidence interval and Cox-regression for multivariate analysis. Localization of tumor, clinical and pathological, tumor and lymph node stage, number of metastatic lymph nodes, perinodal invasion, and differentiation were evaluated as variables.

  • Top
  • Abstract
  • Introduction
  • Methods
  • Results
  • Disscussion
  • References
  • Results
    The study population consisted of 81 (95.3%) males and 4 (4.7%) females. The mean age of the patients was 57 years (range, 36–86 years). Eight (9.4%) patients underwent partial and 77 patients (90.6%) underwent total laryngectomy. Eighty-one patients had classical SCC and 4 (4.7%) were of the basaloid subtype. Some clinical and prognostic features are given in Table I. Thirty-five cases (41.2%) were supraglottic, 27 (31.8%) were glottic, 4(4.7%) were subglottic, and 19 (22.4%) were transglottic. Pathological T stages were as follows: T2 for 5 patients (5.9%), T3 for 41 patients (48.2%), and T4 for 39 patients (45.9%). Thirty-one patients (48.2%) had no lymph node metastasis (pN0), and the numbers of pN1, pN2, and pN3 cases were 18 (21.2%), 25 (29.4%), and 1 (1.2%) respectively. Twenty patients (23.5%) had perinodal invasion. All patients were considered for post-operative radiotherapy for the following reasons: pT stages 3 and 4, pN (+), patients with pT2 and a positive surgical margin, and/or subglottic extension. All patients received adjuvant radiotherapy, and received concomitant chemotherapy according to the criteria described above.


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    Table I: Demographical and prognostic distributions of all cases according to proportion of tumor-stroma

    Median follow up was 48 months (range 3-194). The mean TSP was 48.63+18.18. There was no difference for TSP when sex, tumor location, tumor grade, pathological and clinical tumor and lymph node stage, and perinodal invasion were considered (p=0.36, p=0.21,p=0.24, p=0.41, p=0.40, p=0.83, respectively). Although statistically insignificant, the mean TSP was the lowest for subglottic carcinomas compared with supraglottic, transglottic and glottic cases (37.46+12.49, 52.41+37.47, 50.86+19.84 and 44.56+16.91, respectively). Also TSP was lowest in cases with perinodal invasion compared with cases with metastasis but no perinodal invasion and highest in cases without lymph node metastasis (44.72+20.23, 47.77+17.37, 50.05+17.34, respectively). The mean value of TSP was higher in basaloid subtype compared with the classical SCC cases (53.76±14.70 and 48.63±18.38, respectively).

    The overall and disease free survival analysis did not reveal significance with log rank for sex, tumor location, tumor grade, clinical tumor and pathological lymph node stage, and perinodal invasion as well as TSP, but significance for clinical lymph node stage (p=0.036), pathological T stage (p=0.01), pathological stage (p=0.016) and number of metastatic lymph nodes (p=0.00) (Figure 2, Table II). Only pathological stage was an independent factor with coxregression for overall survival with 95% confidence interval (p=0.008, hazard ratio=1.003; lower: 1.001, upper: 1.005) among the latter four features with statistical significance.


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    Figure 2: Graphic for overall survival.


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    Table II: Overall survival analysis with Log rank and “p” value. The standard error was calculated with 95% confidence interval

  • Top
  • Abstract
  • Introduction
  • Methods
  • Results
  • Disscussion
  • References
  • Discussion
    Recent findings highlight the importance of TSP as a prognostic marker in some types of cancer5-11. High proportion of stroma seems to be a poor prognostic marker5-11.

    The importance of tumor-stroma interaction was recognized a long time ago. Stephan Paget, a surgeon and son of Sir James Paget who is recognized as the founder of scientific medical pathology, proposed the “seed and soil” hypothesis in 1889. He concluded that “the best work in pathology of cancer is done by who are studying the nature of the seed (the cancer cell); the observations of the soil (the secondary organ) may also be useful”26. During the last three decades there is increasing evidence that support the role of tumor stroma in tumor invasion, metastasis, progression and prognosis.

    In 1993 Dingemans et al. presented the infiltrative phenotype of colon carcinoma cells when transplanted into granulation tissue while they formed encapsulated and well differentiated tumors at undisturbed subcutaneous tumors in an experimental model27. This study presented direct evidence for the importance of tumor stroma in the prognostic phenotypical features of tumor growth like the infiltrative pattern. Many other factors about tumor stroma have also been described. The tumor microenvironment consists of extracellular matrix, immune and inflammatory cells, blood vessel cells and myofibroblasts28. The myofibroblasts, fibroblastic cells adjacent to cancer cell nests expressing α-smooth muscle actin, seem to be very important contributors of the tumor stroma through the secretion of matrix metalloproteinases (MMP) and their inhibitors (TIMP), cytokines and chemokines along with the neoplastic cells29. Degradation of the matrix and the MMPs are crucial for invasion and metastasis30. It is suggested that platelet-derived growth factor (PDGF) and transforming growth factor-β (TGF-β) expression induce myofibroblastic cell proliferation31,32. Myofibroblasts are derived either from the bone-marrow or the multiple resident precursors; the endothelial cells, smooth muscle cells, adipocytes and stellate cells29.

    Recently tumor stromal cells have been shown to participate in the Warburg effect in a reverse pattern, through the stimulation of the hydrogen peroxide secretion by the tumor cells inducing pseudohypoxia in the tumor microenviroment. The stromal cells then produce and present L-lactate and ketone as well as nucleotides, fatty acids and amino acids, such as glutamine to the tumor cells as a result of aerobic glycolysis and mitophagy33,34. All these above mentioned data support the stroma as an important predictor of tumor behavior.

    The association of hypoxia, fibrosis and poor prognosis has been recognized in various tumors for some time35. The production of more growth factors by more stromal cells and the encapsulation of the tumor cells by fibrosis not allowing the penetration of the immune response were proposed to explain this association along with the mechanisms described above32,33,37,38. Depending upon all these findings, the morphological quality and quantity of tumor stroma is evaluated in different tumors as prognostic markers. The properties of the stroma are described as a prognostic marker in rectal cancer by Ueno et al who proposed mature, intermediate and immature categories12. They identified more tumor budding, which is also a poor prognostic factor in colorectal carcinomas as well as poor prognosis in cases with immature stroma12,38,39.

    The quantity of stroma or stromal components was also described as prognostic features. Sis et al. reported desmoplasia measured by computer assisted image analysis in van Gieson stained sections as a poor prognostic factor in colorectal carcinoma13. Mesker et al. proposed carcinoma stroma ratio as a prognostic marker in colorectal carcinomas6. They estimated the TSP in tumor sections and the scored lowest percentage was considered as decisive. In this study, 50% was accepted as the cutoff point for dichotomatous categorization, and they identified tumor percentage as an independent prognostic factor in Cox regression analysis. This was followed by the study in oesophageal adenocarcinoma by Courrech Staal et al., the same method was applied but in this study “tumor-stroma ratio” terminology was used instead of percentage and the tumor stroma ratio was identified as a highly significant prognostic factor9. Moorman et al10 and de Kruijf et al.8 presented the prognostic value of tumor-stroma ratio in triple negative breast adenocarcinomas with methods similar to Mesker et al6. The importance of the tumor stroma ratio is also validated by the morphometric study by West et al. in colorectal adenocarcinomas7.

    The above mentioned findings are in favor of TSP as a prognostic factor for adenocarcinomas, but there is no information about SCC other than articles about desmoplasia. The association of desmoplastic response and unfavorable prognostic histopathological findings and recurrences were described for skin SCC14-17. de Diego SJI (40) could not detect any relationship between desmoplasia with local recurrence in laryngeal and hypopharyngeal carcinomas, but Prim et al.41 presented the desmoplasia at metastatic lymph nodes as a prognostic marker. Zidar et al. reported well differentiated SCC morphology and desmoplasia association in laryngeal SCC but they did not present prognostic data42. Tumor budding, a poor prognostic finding related to the type of desmoplasia in colorectal carcinomas, is also described as a prognostic marker for laryngeal SCC12,25. Based on the lack of information about TSP in laryngeal carcinomas and the above mentioned findings, we investigated if there was any relationship between TSP and histopathological findings and survival in laryngeal SCC.

    Two methods were applied in the previous series in order to determine TSP. de Kruijf et al.8, and Courrech Staal et al.9 applied the methodology described by Mesker WE et al.6, and they used semiquantitative measurements depending upon the estimation of the pathologists by visual inspection, while West et al.7 performed point counting with a grid of 300 points and counted tumorstroma proportion in a 9 mm2 tumor region. While the former authors had selected the deepest invasive border of the neoplastic lesions at the most stroma rich regions, West et al7 preferred selecting areas from the luminal surface with greatest tumor cell density. These methodological differences highlight the requirement for a standard method for these measurements. In our series, we evaluated the cases as described by Mesker et al, including the invasive border but also we developed and used software allowing precise measurement in a short time. The cut point was 50% in previous series as described originally by West et al. and we used the mean value of 48.63 which was pretty close to this value7.

    The prognostic factors in laryngeal carcinomas include tumor location, tumor type, pathological T and N stage, grade, lymphovascular invasion, perineural invasion and perinodal invasion20-23,41,42. In this series, some of the robust prognostic markers like tumor location, grade, tumor and lymph node stage were not identified as prognostic factors as well as TSP and only pathological stage was an independent prognostic factor for overall survival. Although there are conflicting results about SCC of the larynx in terms of desmoplasia, histopathological prognostic features and prognosis, considering the results in this series it is hard to conclude that the TSP is not a prognostic marker in laryngeal carcinomas40-42. Although statistically insignificant, the lower TSP identified associated with lymph node metastasis and perinodal invasion as well as subglottic localization, which are poor prognostic factors in laryngeal carcinomas, suggests that further evaluation may provide significant results.

    It seems TSP is an important factor that needs further evaluation in SCC as well as adenocarcinomas. Although we could not find statistical significance in this series for TSP, the quantitative method described in this series might be helpful for determining TSP in other series.

  • Top
  • Abstract
  • Introduction
  • Methods
  • Results
  • Discussion
  • References
  • References

    1) De Wever O, Mareel M: Role of tissue stroma in cancer cell invasion. J Pathol 2003, 4:429-447 [ PubMed ]

    2) Ohtani H: Stromal reaction in cancer tissue: pathophysiologic significance of the expression of matrix-degrading enzymes in relation to matrix turnover and immune/inflammatory reactions. Pathol Int 1998, 1:1-9 [ PubMed ]

    3) Halvorsen TB, Seim E: Association between invasiveness, inflammatory reaction, desmoplasia and survival in colorectal cancer. J Clin Pathol 1989, 2:162-166 [ PubMed ]

    4) Tuxhorn JA, Ayala GE, Smith MJ, Smith VC, Dang TD, Rowley DR: Reactive stroma in human prostate cancer: induction of myofibroblast phenotype and extracellular matrix remodeling. Clin Cancer Res 2002, 9: 2912-2923 [ PubMed ]

    5) Yanagisawa N, Li R, Rowley D, Liu H, Kadmon D, Miles BJ, Wheeler TM, Ayala GE: Stromogenic prostatic carcinoma pattern (carcinomas with reactive stromal grade 3) in needle biopsies predicts biochemical recurrence-free survival in patients after radical prostatectomy. Hum Pathol 2007, 11:1611-1620 [ PubMed ]

    6) Mesker WE, Junggeburt JM, Szuhai K, de Heer P, Morreau H, Tanke HJ, Tollenaar RA: The carcinoma-stromal ratio of colon carcinoma is an independent factor forsurvival compared to lymph node status and tumor stage. Cell Oncol 2007, 5:387-398 [ PubMed ]

    7) West NP, Dattani M, McShane P, Hutchins G, Grabsch J, Mueller W, Treanor D, Quirke P, Grabsch H: The proportion of tumour cells is an independent predictor for survival in colorectal cancer patients. Br J Cancer 2010, 10:1519-1523 [ PubMed ]

    8) de Kruijf EM, van Nes JG, van de Velde CJ, Putter H, Smit VT, Liefers GJ, Kuppen PJ, Tollenaar RA, Mesker WE: Tumor-stroma ratio in the primary tumor is a prognostic factor in early breast cancer patients, especially in triple-negative carcinoma patients. Breast Cancer Res Treat 2011,3:687-696 [ PubMed ]

    9) Courrech Staal EF, Wouters MW, van Sandick JW, Takkenberg MM, Smit VT, Junggeburt JM, Spitzer-Naaykens JM, Karsten T, Hartgrink HH, Mesker WE, Tollenaar RA: The stromal part of adenocarcinomas of the oesophagus: does it conceal targets for therapy? Eur J Cancer 2010,4:720-728 [ PubMed ]

    10) Moorman AM, Vink R, Heijmans HJ, van der Palen J, Kouwenhoven EA:The prognostic value of tumour-stroma ratio in triple-negative breast cancer. Eur J Surg Oncol 2012,4:307-313 [ PubMed ]

    11) Maeshima AM, Niki T, Maeshima A, Yamada T, Kondo H, Matsuno Y: Modified scar grade: a prognostic indicator in small peripheral lung adenocarcinoma. Cancer 2002, 12:2546-2554 [ PubMed ]

    12) Ueno H, Jones AM, Wilkinson KH, Jass JR, Talbot IC: Histological categorisation of fibrotic cancer stroma in advanced rectal cancer. Gut 2004,4:581-586 [ PubMed ]

    13) Sis B, Sarioglu S, Sokmen S, Sakar M, Kupelioglu A, Fuzun M: Desmoplasia measured by computer assisted image analysis: an independent prognostic marker in colorectal carcinoma. J Clin Pathol 2005,1:32-38 [ PubMed ]

    14) Quaedvlieg PJ, Creytens DH, Epping GG, Peutz-Kootstra CJ, Nieman FH, Thissen MR, Krekels GA: Histopathological characteristics of metastasizing squamous cell carcinoma of the skin and lips. Histopathology 2006, 3:256-264 [ PubMed ]

    15) Brantsch KD, Meisner C, Schönfisch B, Trilling B, Wehner-Caroli J, Röcken M, Breuninger H: Analysis of risk factors determining prognosis of cutaneous squamous-cell carcinoma: a prospective study. Lancet Oncol 2008, 8:713-720 [ PubMed ]

    16) Häfner HM, Breuninger H, Moehrle M, Trilling B, Krimmel M: 3D histology-guided surgery for basal cell carcinoma and squamous cell carcinoma: recurrence rates and clinical outcome. Int J Oral Maxillofac Surg 2011, 9:943-948 [ PubMed ]

    17) Breuninger H, Brantsch K, Eigentler T, Häfner HM: Comparison and evaluation of the current staging of cutaneous carcinomas. J Dtsch Dermatol Ges 2012, [ PubMed ]

    18) Salmon PJ, Hussain W, Geisse JK, Grekin RC, Mortimer NJ. Sclerosing squamous cell carcinoma of the skin, an underemphasized locally aggressive variant: a 20-year experience. Dermatol Surg 2011,5:664-670 [ PubMed ]

    19) Rafferty MA, Fenton JE, Jones AS:The history, aetiology and epidemiology of laryngeal carcinoma. Clin Otolaryngol Allied Sci. 2001, 26:442-446 [ PubMed ]

    20) Silvestri F, Bussani R, Stanta G, Cosatti C, Ferlito A: Supraglottic versus glottic laryngeal cancer: epidemiological and pathological aspects. ORL J Otorhinolaryngol Relat Spec 1992, 1:43-48 [ PubMed ]

    21) Barona de Guzmán R, Martorell MA, Basterra J, Armengot M, Alvarez-Valdés R, Garin L: Prognostic value of histopathological parameters in 51 supraglottic squamous cell carcinomas. Laryngoscope 1993, 5:538-540 [ PubMed ]

    22) Ozdek A, Sarac S, Akyol MU, Unal OF, Sungur A: Histopathological predictors of occult lymph node metastases in supraglottic squamous cell carcinomas. Eur Arch Otorhinolaryngol 2000, 389-392 [ PubMed ]

    23) Oosterkamp S, de Jong JM, Van den Ende PL, Manni JJ, Dehing-Oberije C, Kremer B: Predictive value of lymph node metastases and extracapsular extension for the risk of distant metastases in laryngeal carcinoma. Laryngoscope 2006, 11:2067-2070 [ PubMed ]

    24) Akman FC, Dag N, Ataman OU, Ecevit C, Ikiz AO, Arslan I, Sarioglu S, Ada E, Kinay M; Dokuz Eylül Head and Neck Tumour Group (DEHNTG): The impact of treatment center on the outcome of patients with laryngeal cancer treated with surgery and radiotherapy. Eur Arch Otorhinolaryngol 2008, 101:245-255 [ PubMed ]

    25) Sarioglu S, Acara C, Akman FC, Dag N, Ecevit C, Ikiz AO, Cetinayak OH, Ada E; for Dokuz Eylül Head and Neck Tumour Group (DEHNTG:Tumor budding as a prognostic marker in laryngeal carcinoma. Pathol Res Pract 2010, 2:88-92 [ PubMed ]

    26) Paget S: The distribution of secondary growths in cancer of the breast. 1889. Cancer Metastasis Rev 1989, (2):98-101 [ PubMed ]

    27) Dingemans KP, Zeeman-Boeschoten IM, Keep RF, Das PK: Transplantation of colon carcinoma into granulation tissue induces an invasive morphotype. Int J Cancer 1993, 6:1010-1016 [ PubMed ]

    28) Zhang W, Huang P: Cancer-stromal interactions: role in cell survival, metabolism and drug sensitivity. Cancer Biol Ther 2011, 2:150-156 [ PubMed ]

    29) De Wever O, Demetter P, Mareel M, Bracke M: Stromal myofibroblasts are drivers of invasive cancer growth. Int J Cancer 2008, 10:2229-2238 [ PubMed ]

    30) Sarioglu S, Ozer E, Kirimca F, Sis B, Pabuccuoglu U. Matrix metalloproteinase-2 expression in laryngeal preneoplastic and neoplastic lesions. Pathol Res Pract. 2001;197:483-486 [ PubMed ]

    31) Shao ZM, Nguyen M, Barsky SH: Human breast carcinoma desmoplasia is PDGF initiated. Oncogene 2000, 38:4337-4345 [ PubMed ]

    32) De Wever O, Mareel M: Role of tissue stroma in cancer cell invasion. J Pathol 2003, 4:429-447 [ PubMed ]

    33) Witkiewicz AK, Kline J, Queenan M, Brody JR, Tsirigos A, Bilal E, et al: Molecular profiling of a lethal tumor microenvironment, as defined by stromal caveolin-1 status in breast cancers. Cell Cycle 2011, 10:1794-1809 [ PubMed ]

    34) Witkiewicz AK, Whitaker-Menezes D, Dasgupta A, Philp NJ, Lin Z, Gandara R, Sneddon S, Martinez-Outschoorn UE, Sotgia F, Lisanti MP: Using the "reverse Warburg effect" to identify high-risk breast cancer patients: stromal MCT4 predicts poor clinical outcome in triple-negative breast cancers. Cell Cycle 2012, 6:1108-1117 [ PubMed ]

    35) Colpaert CG, Vermeulen PB, Fox SB, Harris AL, Dirix LY, Van Marck EA: The presence of a fibrotic focus in invasive breast carcinoma correlates with the expression of carbonic anhydrase IX and is a marker of hypoxia and poor prognosis. Breast Cancer Res Treat 2003,2:137-147 [ PubMed ]

    36) Cooper R, Sarioglu S, Sokmen S, Fuzun M, Kupelioglu A, Valentine H, Gorken IB, Airley R, West C: Glucose transporter-1 (GLUT-1): a potential marker of prognosis in rectal carcinoma? Br J Cancer 2003, 5:870-876 [ PubMed ]

    37) Kouniavsky G, Khaikin M, Zvibel I, Zippel D, Brill S, Halpern Z, Papa M: Stromal extracellular matrix reduces chemotherapy-induced apoptosis in colon cancer cell lines. Clin Exp Metastasis 2002, 1:55-60 [ PubMed ]

    38) Sert Bektaş S, Inan Mamak G, Cırış IM, Bozkurt KK, Kapucuoğlu N: Tumor budding in colorectal carcinomas. Turk Patoloji Derg 2012, 1:61-66 [ PubMed ]

    39) Ueno H, Hashiguchi Y, Kajiwara Y, Shinto E, Shimazaki H, Kurihara H, Mochizuki H, Hase K: Proposed objective criteria for "grade 3" in early invasive colorectal cancer. Am J Clin Pathol 2010, 2:312-22 [ PubMed ]

    40) de Diego Sastre JI, Prim Espada MP, Hardisson Hernáez D, Gavilán Bouzas J: The impact of extracapsular spread and desmoplasia on local recurrence in patients with malignant tumors of the larynx and hypopharynx. Acta Otorrinolaringol Esp 1999 6:459-462 [ PubMed ]

    41) Prim MP, De Diego JI, Hardisson D, Madero R, Nistal M, Gavilán J: Extracapsular spread and desmoplastic pattern in neck lymph nodes: two prognostic factors of laryngeal cancer. Ann Otol Rhinol Laryngol 1999,7: 672-676 [ PubMed ]

    42) Zidar N, Gale N, Kambic V, Fischinger J: Proliferation of myofibroblasts in the stroma of epithelial hyperplastic lesions and squamous carcinoma of the larynx. Oncology 2002,4:381-385 [ PubMed ]

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  • References
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