Journal of Digestive Disorders And Diagnosis
Current Issue
Volume No: 1 Issue No: 1

Case-report Article | Open Access
  • Available online freely| Peer Reviewed
  • Adenosquamous Cell Carcinoma Of The Stomach 18F-FDG PET/CT Diagnosis And Review Of Literature

    M Darouichi 1
        S Jovanovic 2     P Constanthin 3    

    1 Department of radiology 

    2 Institute medical champel 

    3 Department Neurosciences UniversityGeneva Switzerland 

    Abstract

    Adenosquamous carcinoma of the stomach (ASCS) is extremely rare with less than one hundred cases published in the world literature. It is defined by combined adenocarcima and squamous cells carcinoma of the stomach. ASCS is clinically aggressive and has a poor prognosis, even when discovered at an early stage. This intriguing entity is characterized by non specific symptoms or radiological signs. Integrate 18F-fluorodeoxyglucose positron emission tomography/computed tomography 18F FDG.PET/CT is useful morphologic and functional modalities for evaluating primary tumor, local extend and invasion beyond gastric wall or distant metastatic and eventually for management. Diagnosis of ASCS requires immunohistochemical confirmation. We report a 77-year-old man who was admitted to hospital because of epigastric pain, vomiting and melena since more than a month. Gastroscopy with biopsies had initially suggested gastric squamous cell carcinoma .Thoracic and abdominal computed tomography scan (CT) showed a huge mass in the gastric body, largely necrotic, infiltrating the adjacent structures without metastases. Partial gastrectomy with resection of the proximal 2/3 of the stomach, the spleen, the body and tail of pancreas and the left transverse colon was performed. Immunohistochemical analysis demonstrated ASCS with mixed adenocarcinomatous and squamous cells carcinoma with invasion of gastric lymph nodes. Unfortunately, two months after surgery, a CT of the abdomen revealed diffuse metastasis and the patient died three months later.

    In light of this case, we discuss the pathogenesis, staging and monitoring of this rare entity by combined 18F-FDG PET/CT with review of the literature.

    Author Contributions

    Received Sep 29, 2016;     Accepted Oct 18, 2016;     Published Nov 01, 2016;

    Academic Editor: Divey Manocha

    Affilation: Upstate Medical University

    Copyright© 2016 M Darouichi, et al.
    License
    Creative Commons License   This work is licensed under a Creative Commons Attribution 4.0 International License. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

    Competing interests

    The authors have declared that no competing interests exist.

    Funding Interests:

    Citation:

    M Darouichi, S Jovanovic, P Constanthin (2016) Adenosquamous Cell Carcinoma Of The Stomach 18F-FDG PET/CT Diagnosis And Review Of Literature Journal of Digestive Disorders And Diagnosis. - 1(1):20-27
    DOI 10.14302/issn.2574-4526.jddd-16-1311

    Introduction

    Introduction

    Adenosquamous carcinoma (ASCS) is an exceedingly rare neoplasm of the stomach. This tumor consists in varying proportions of adenocarcinoma and squamous cell carcinomas. The incidence of this entity varies between 0, 04 and 0, 07% of gastric cancer and less one hundred cases are described in the literature. We present one case of ASCS in a 77 year-old man. In light of this observation we discuss than several hypothesis of pathogenesis and the fundamental role of combined fluorine-18 fluorodeoxyglucose imaging PET and computed tomography (18F-FDG.PET/CT) in staging and monitoring this unusal tumor.

    Discussion

    Discussion

    Among carcinomas of the stomach, adenocarcinomas are the most prevalent type, and adenosquamous carcinoma (ADSC) or squamous cells carcinoma are excedentely rare representing respectively 0.07 and 0, 04 % of all gastric carcinomas, according to the WHO criteria of histological classification of stomach tumors 1. These aggressive tumors occur in patients with an average age between 50 and 70 years and with a male-female ratio 4:1 2.

    ASCS consists a mix of varying proportion of adenocarcima cells and squamous cells carcinoma, but the later component by definition should exceed 25% of tumor gastric mass 3. This is also entity is most commonly developed at the sites where adenocarcinoma typically arise such as stomach, intestine 4 and uterus 5 but it's reported in the esophagus 6, anus and vagina where squamous cells carcinoma are more frequently encountered.

    Many authors now believe that this kind of carcinoma results from two theories, either transforming or collision 7. In the first one, the adenocarcinoma is transforming into squamous cells carcinoma. The collision theory proposes that adenocarcinoma and squamous cell carcinoma arise independently from different sites and ultimately coalesce 8.

    Furthermore, Boswell and Helwig 9 considered these following criteria to allow the diagnosis of SSC: 1. Keratinizing cells with typical pearl formation, 2. Mosaic pattern of cells arrangement in which cell borders are sharp, 3. Intercellular bridges and 4. High concentration of sulfhydryl indicates the presence of keratin or prekeratin.

    In spite of that, the exact histogenesis of the ASCS is not yet clear; however, multiple hypotheses are postulated 10: 1. Squamous metaplasia of an adenocarcinoma; 2. Cancerization of metaplastic non neoplastic squamous cells; 3. Cancerization of ectopic squamous epithelium; 4. Differentiation of multipotential undifferentiated cancer cells toward both squamous and glandular cells and 5. Collision of concurrent adenocarcinoma and squamous cell carcinoma.

    Our present case seems to support these hypotheses theories for 4 reasons: the tumor showed keratinizing cell masses, mosaic patterns, intercellular bridges and adenocarcinoma components.

    Preoperative diagnosis of ASCS of the stomach is difficult and is challenging. There are no specific clinical symptoms or defining radiological imaging that would differentiate this neoplasm from the more common gastric tumors.

    The symptoms are nonspecific including vague abdominal pain, melena, diarrhea and weight loss 11 and ASCS is usually found at an advanced stage with invasion of the neighboring structures with local lymph nodal and other organs metastasis.

    The American Joint Committee on Cancer (AJCC), staging system is widely used for the characterization of disease, burden and prognosis in gastric cancer 12. Thereby, the combined 18F-FDG PET/CT may be useful in the preoperative assessment and therapeutic monitoring of patients with gastric cancers 13. It helps in detection of primary tumor; extension of disease in stomach and surrounding structures, local and distant lymph node and solid organ metastasis and peritoneal dissemination 14.

    Over the last two decades, thin section with multiplanar reconstruction CT scan combined to 18F-FDG PET have dramatically increased the impact of management of gastric tumors at different stages. Correlating anatomic information and functional modalities help for diagnosis, pre operative staging of the ASCS and for monitoring treatment effect.

    CT scan is an accurate anatomical imaging for determination of preoperative T stage. In spite, 18F-FDG PET cannot be helpful in determinated the exact T stage because prominent uptake averaged across several millimeters, a distance too great to give confidence when assessing barrier invasion on the surface of organs such as present case 15.

    Moreover, CT Scan identify positive lymph nodes metastasis based on size, shape, central necrosis and heterogeneity confirms metastatic involvement in stage I and II but cannot distinguish between reactive hyperplasia or metastatic enhancement 15. Whereas, 18F-FDG PET detects lymph node metastases in stage III and IV beyond compartment I and II and also small lymph nodes (less than 1 cm) which are metabolically active of metastatic disease 16.

    For metastases, 18F FDG PET may be more accurate than the anatomical imaging modalities in the detection of metabolic distant metastases, and liver metastases smaller than 1 cm missed during the portal venous or arterial phase on CT scan 17. The limitations of 18F FDG PET are not tumor-specific as it is also positive by inflammatory cells or peritoneal metastases 18 and small lung metastases (less than one cm) 18. In a recent study 19, the sensitivity of CT and 18F-FDG PET in the evaluation of pulmonary nodules was 93% and 57%, respectively.

    Despite technical advances in gastroenterology and imaging in the early detection of ASCS, the diagnosis is often made after the tumor has already metastasized to the regional and distant lymph nodes, liver or lung, such as in our patient. Accurate preoperative diagnosis of ASCS is made with great difficulties since there are no imaging studies that would differentiate it from squamous cell carcinoma, adenocarcinoma, lymphoma, gastrointestinal stromal tumor (GIST) or more benign stomach neoplasm 20. In any case the diagnosis of ASCS is mainly based on the histological exams and requires immunohistochemical assessment of tumor tissue.

    Complete resection of the gastric tumor and adjacent lymph nodes represents the only effective curative treatment 21. The role of radiotherapy and chemotherapy after surgery is controversial but suggested by some authors to reduce the risk of recurrence 22.

    Despite the recent advances in diagnosis and therapy, the mortality with ASCS sremains substantial. Patient's outcome after resection of ASCS is generally poor. The typically advanced stages at the time of initial diagnosis explain this outcome. ADSC of the stomach is more aggressive than other histological types of gastric carcinomas 23. The median survival from the time of diagnosis is shorter than for adenocrcinoma and squamous cell carcinoma 24. Moreover, ASCS has a high rate or early metastases despite good differentiation 25.

    It is not surprising that survival was not prolonged in our patient who had an ASCS and a rapid systemic metastasis less than three months after.

    Conclusion

    Conclusion

    The ASCS is a rare malignancy, characterized by a particularly aggressive potential and poor prognosis. It is often found at the stage of digestive complications with extensive visceral invasion and metastasis. Early diagnosis of ASCS has important implications for surgical management at presentation and afterward. The combined use of CT and 18F-FDG PET may be useful in the preoperative staging and helpful in the follow up of patients undergoing chemotherapy but the diagnosis remains based on immunohistochemical exams.

    References

    1. Jalif AR, López OJ, Díaz de Battaglini SM, Bur EG. (1984) Gastric adenoacanthoma Report of a case and review of the literature Acta Gastroenterol Latinoam. 14(1):79-84.
    2. Blázquez S, Raventós A, Díaz ML, García-Fontgivell JF, Martínez S (2005) Sirvent JJ: Adenosquamous gastric carcinoma in Caucasian patient Rev Esp Enferm Dig. 97:211-212.
    3. Mingazzini PL, Barsotti P, Malchiodialbedi F. (1983) Adenosquamous carcinoma of the stomach: Histological, histochemical and ultrastructural observations Histopathology. 7:433-443.
    4. Cagir B, Nagy MW, Topham A, Rakinic J, Fry RD (1973 Aug) Adenosquamous carcinoma of the colon, rectum, and anus: epidemiology, distribution, and survival characteristics Am J Clin Pathol. 60(2):208-17.
    5. Morrison DL. (1966 Aug) Adenoacanthoma of the uterine body J Obstet Gynaecol Br Commonw. 73(4):605-610.
    6. Francioni F, Tsagkaropoulos S, Telha V, Barile La Raia R, De Giacomo T (2012 Apr) Adenosquamous carcinoma of the esophagogastric junction Case report. 33(4):123-5.
    7. Mori M, Iwashita A, Enjoji M. (1986) Squamous cell carcinoma of the stomach: report of three cases Am J Gastroenterol. 81:339-342.
    8. Straus R, Heschel S, Fortmann DJ. (1969) Primary adenosquamous carcinoma of the stomach, A case report and review Cancer. 24:985-995.
    9. Boswell JT, Helwig EB. (1965) Squamous cell carcinoma and adenocanthoma of the stomach Cancer. 18: 181-192.
    10. Kazuhiro Yoshida. et al. (1996) Early Gastric Cancer of Adenosquamous Carcinoma Type: Report of a Case and Review of Literature Jpn J Clin Oncol. 26: 252-257.
    11. Manna ED, Seixas AA, de Araújo RP, Ferro MC. (1998) Primary adenosquamous carcinoma of the stomach Rev Assoc Med Bras. 44:152-154.
    12. (2010 Jun) The American Joint Committee on Cancer: the 7th ed of the AJCC cancer staging manual and the future of TNM Ann Surg Oncol. 17(6):1471-4. doi: 10.1245/s10434-010-0985-4.
    13. Smyth EC, Shah MA. (2011 Dec 14) Role of 18F 2-fluoro-2-deoxyglucose positron emission tomography in upper gastrointestinal malignancies World J Gastroenterol. 17(46):5059-74. doi: 10.3748/wjg.v17.i46.5059.
    14. Mukai K, Ishida Y, Okajima K, Isozaki H, Morimoto T et al. (2006) Usefulness of preoperative FDG-PET for detection of gastric cancer Gastric Cancer. 9: 192-196 63.
    15. Koga H, Sasaki M, Kuwabara Y et al. (2003) An analysis of the physiological FDG uptake pattern in the stomach Ann Nucl Med. 17: 733-738.
    16. Yun M, Lim JS, Noh SH, Hyung WJ, Cheong JH et al. (2005) Lymph node staging of gastric cancer using (18)F-FDG PET: a comparison study with CT J Nucl Med. 46: 1582-1588.
    17. Yang QM, Kawamura T, et al. (2008) PET-CT suitable for predicting lymph node status for gastric cancer? Hepatogastroenterology. 55: 782-785.
    18. Lim JS, Kim MJ, Yun MJ. et al. (2006) Comparison of CT and 18F-FDG pet for detecting peritoneal metastasis on the preoperative evaluation for gastric carcinoma Korean J Radiol. 7: 249-256.
    19. Jared A.Christensen. et al. (2006) Characterization of the Solitary Pulmonary Nodule: 18F-FDG PET Versus Nodule-Enhancement CT, AJR 187:1361-1367.
    20. Tian J, Chen L, Wei B. et al. (2004) The value of vesicant 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) in gastric malignancies Nuclear Medicine Communications. 25(8):825-31.
    21. Gouzi JL, Huguier M, Fagniez PL. et al. (1989) Total versus subtotal gastrectomy for adenocarcinoma of the gastric antrum: a French prospective controlled study Ann Surg. 209:162-166.
    22. Ott K, Fink U, Becker K. et al. (2003) Prediction of response to preoperative chemotherapy in gastric carcinoma by metabolic imaging: results of a prospective trial Journal of Clinical Oncology. 21(24):4604-10.
    23. Quan J, Zhang R, Liang H, Li F, Liu H (2013 May) The clinicopathologic and prognostic analysis of adenosquamous and squamous cell carcinoma of the stomach Am Surg. 79(5):E206-8.
    24. Toyota N, Minagi S, Takeuchi T, Sadamitsu N. (1996 Feb) Adenosquamous carcinoma of the stomach associated with separate early gastric cancer (type IIc) J Gastroenterol. 31(1):105-8.
    25. Aoki Y, Tabuse K, Wada M, Katsumi M, Uda H (1978) Primary adenosquamous carcinoma of the stomach: experience of 11 cases and its clinical analysis Gastroenterol Jpn. 13:140-145.
    Affiliations:
    Affiliations: