Abstract
PURPOSE: This study was designed to evaluate the accuracy of preoperative staging by transrectal ultrasonography (TRUS) and to clarify the limitations and pitfalls of TRUS by clinicopathologic analysis for staging errors. MATERIALS AND METHODS: Results of TRUS for 164 consecutive patients with rectal cancer were compared prospectively with histopathologic findings according to the newest TNM classification. Clinicopathologic factors that may influence staging errors were analyzed by reviewing both resected specimens and hard copies of TRUS. RESULTS: There were 13 patients histopathologically staged as pTis, 21 as pT1, 34 as pT2, 84 as pT3, 12 as pT4, 73 as pN0, and 91 as pN1–3. Of these, 85, 86, 56, 93, 75, 74, and 77 percent, respectively, were correctly staged by TRUS. Excluding 12 cases with incomplete examinations because of annular constricting tumors, overstaging of tumor invasion depth was mostly caused by tumor invasion close to the deeper uninvolved layer, inflammatory cell aggregation, desmoplastic change, and hypervascularity around the tumor, mimicking tumor invasion on TRUS. The understaging was mostly the result of microscopic invasion beyond the estimated layers and difficulties in examination because of the tumor location being close to the anal canal or on the Houston's valves or the tumor shapes being polypoid or bulky and fungating. Overstaging in lymph node status was caused by reactive lymph node swelling and understaging by the presence of only small involved node and metastasis in the extramesorectal nodes. CONCLUSIONS: An awareness of the limitations and pitfalls of TRUS, as demonstrated by the present study, should improve staging accuracy and contribute to optimum clinical decision-making.
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Saitoh N, Okui K, Sarashina H, Suzuki M, Arai T, Nunomura M. Evaluation of echographic diagnosis of rectal cancer using intrarectal ultrasonic examination. Dis Colon Rectum 1986;29:234–42.
Yamashita Y, Machi J, Shirouzu K, Morotomi T, Isomoto H, Kakegawa T. Evaluation of endorectal ultrasound for the assessment of wall invasion of rectal cancer: report of a case. Dis Colon Rectum 1988;31:617–23.
Rifkin MD, Ehrlich SM, Marks G. Staging of rectal carcinoma: prospective comparison of endorectal US and CT. Radiology 1989;170:319–22.
Konishi F, Ugajin H, Ito K, Kanazawa K. Endorectal ultrasonography with a 7.5 MHz linear array scanner for the assessment of invasion of rectal carcinoma. Int J Colorectal Dis 1990;5:15–20.
Glaser F, Schlag P, Herfarth CH. Endorectal ultrasonography for the assessment of invasion of rectal tumours and lymph node involvement. Br J Surg 1990;77:883–7.
Tio TL, Coene PP, van Delden OM, Tytgat GN. Colorectal carcinoma: preoperative TNM classification with endosonography. Radiology 1991;179:165–70.
Milsom JW, Lavery IC, Stolfi VM,et al. The expanding utility of endoluminal ultrasonography in the management of rectal cancer. Surgery 1992;112:832–41.
Katsura Y, Yamada K, Ishizawa T, Yoshinaka H, Shimazu H. Endorectal ultrasonography for the assessment of wall invasion and lymph node metastasis in rectal cancer. Dis Colon Rectum 1992;35:362–8.
Herzog U, von Flue M, Tondelli P, Schuppisser JP. How accurate is endorectal ultrasound in the preoperative staging of rectal cancer? Dis Colon Rectum 1993;36:127–34.
Solomon MJ, McLeod RS. Endoluminal transrectal ultrasonography: accuracy, reliability, and validity. Dis Colon Rectum 1993;36:200–5.
Beynon J, Mortensen NJ, Foy DM, Channer JL, Rigby H, Virjee J. Preoperative assessment of mesorectal lymph node involvement in rectal cancer. Br J Surg 1989;76:276–9.
Hildebrandt U, Klein T, Feifel G, Schwarz HP, Koch B, Schmitt RM. Endosonography of pararectal lymph nodes,in vitro andin vivo evaluation. Dis Colon Rectum 1990;33:863–8.
Beynon J, Mortensen NJ, Foy DM, Channer JL, Virjee J, Goddard P. Pre-operative assessment of local invasion in rectal cancer: digital examination, endoluminal sonography or computed tomography? Br J Surg 1986;73:1015–7.
Waizer A, Powsner E, Russo I,et al. Prospective comparative study of magnetic resonance imagingversus transrectal ultrasound for preoperative staging and follow-up of rectal cancer: preliminary report. Dis Colon Rectum 1991;34:1068–72.
Thaler W, Watzka S, Martin F,et al. Preoperative staging of rectal cancer by endoluminal ultrasound vs. magnetic resonance imaging, preliminary results of a prospective comparative study. Dis Colon Rectum 1994;37:1189–93.
International Union Against Cancer. TNM atlas, illustrated guide to the TNM/pTNM-classification of malignant tumours. 3rd ed. Berlin: Springer-Verlag, 1989.
International Union Against Cancer. TNM classification of malignant tumours. 4th ed. Berlin: Springer-Verlag, 1992.
Boyce GA, Sivak MV, Lavery IC,et al. Endoscopic ultrasound in the pre-operative staging of rectal carcinoma. Gastrointest Endosc 1992;38:468–71.
Kimmey MB, Martin RW, Haggitt RC, Wang KY, Franklin DW, Silverstein FE. Histologic correlates of gastrointestinal ultrasound images. Gastroenterology 1989;96:433–41.
Akasu T, Sunouchi K, Sawada T, Tsioulias GJ, Muto T, Morioka Y. Preoperative staging of rectal carcinoma: prospective comparison of transrectal ultrasonography and computed tomography [abstract]. Gastroenterology 1990;98:A268.
Hulsmans FJ, Tio TL, Fockens P, Bosma A, Tytgat GN. Assessment of tumor infiltration depth in rectal cancer with transrectal sonography: caution is necessary. Radiology 1994;190:715–20.
Hildebrandt U, Beynon J, Feifel G, Mortensen NJ. Endorectal sonography. In: Feifel G, Hildebrandt U, Mortensen NJ, eds. Endosonography in gastroenterology, gynecology and urology. Berlin: Springer-Verlag, 1990:81–130.
Hulsmans FJ, Bosma A, Mulder PJ, Reeders JW, Tytgat GN. Perirectal lymph nodes in rectal cancer:in vitro correlation of sonographic parameters and histopatho-logic findings. Radiology 1992;184:553–60.
Milsom JW, Czyrko C, Hull TL, Strong SA, Fazio VW. Preoperative biopsy of pararectal lymph nodes in rectal cancer using endoluminal ultrasonography. Dis Colon Rectum 1994;37:364–8.
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Supported in part by a Grant-in-Aid for Cancer Research from the Ministry of Health and Welfare in Japan.
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Akasu, T., Sugihara, K., Moriya, Y. et al. Limitations and pitfalls of transrectal ultrasonography for staging of rectal cancer. Dis Colon Rectum 40 (Suppl 10), S10–S15 (1997). https://doi.org/10.1007/BF02062014
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DOI: https://doi.org/10.1007/BF02062014