Critical analysis of mucin and signet ring cell as prognostic factors in an Asian population of 2,764 sporadic colorectal cancers
- 206 Downloads
Conflicting data on the clinicopathological characteristics as well as prognosis and survival of signet ring cell (SRC) and mucinous adenocarcinomas (MA) of the colorectum persist.
Consecutive patients (2,764) with sporadic colorectal cancer from 1999 to 2005 were evaluated. The clinicopathological characteristics of these patients were reviewed. Univariate analysis was performed, and survival curves were constructed using the Kaplan–Meier method. Multivariate analysis assessed independent prognostic factors.
The incidence of MA and SRC is 6% and 1.1%, respectively. MA and SRC tend to occur in patients aged ≤50 years (SRC 33%, MA 22%, ordinary adenocarcinomas (OA) 14%, p = 0.001) and are more commonly right-sided (MA 30%, SRC 27%, OA 19%, p = 0.001) than OA. SRC tend to be poorly differentiated (SRC 77%, MA 26%, OA 6%, p < 0.0001) and have a higher risk of recurrence (SRC 40%, MA 26%, OA 6%, p < 0.0001). SRC and MA are more likely to have locally advanced lesions (T3/T4; SRC 100%, MA 90%, OA 83%, p = 0.002) and lymph node metastases (SRC 89%, MA 61%, OA 52%, p < 0.0001) and present with an advanced stage at diagnosis (stage III/IV SRC 94%, MA 67%, OA 56%, p < 0.0001). SRC has poorer 5-year cancer-specific survival (CSS; 11.1%, 95% confidence interval (CI) 0–22.9%) compared with MA (46.8%, 95% CI 38.6–55.0%) and OA (58.7%, 95% CI 56.5–60.9%, p < 0.001). In a multivariate analysis, SRC is an independent poor prognostic factor (HR 1.9, 95% CI 1.1–3.0) but MA is not.
SRC and MA demonstrate clinicopathologic characteristics suggestive of a different biology compared with OA. In our dataset, SRC has a significantly poorer CSS whereas survival rates for MA are similar to OA. These characteristics are similar in both Asian and Western studies reported. Asian reports however suggest a lower incidence of MA.
KeywordsColorectal mucinous adenocarcinoma Signet ring cell Survival
The authors would like to thank the following people in the preparation of the manuscript: (a) Singapore Polyposis Registry coordinator: Ms Loi TT, Carol, RN Msc (Healthcare); (b) Senior Biostatistician, Department of Clinical Research Singapore General Hospital: Ms Fook-Chong MC, Stephanie, BSc MSc(McGill) CStat; (c) Rest of the contributory authors to the manuscript: Dr Ming-Hian Kam, Dr Hak-Mien Quah, Dr Jit-Fong Lim, Dr Kok-Sun Ho, and A/Prof Choong-Leong Tang.
- 1.Chia KS, Lee HP, Seow A, Shanmugaratnam K. Trends in cancer incidence in Singapore, 1968–1992. Singapore Cancer Registry Report No. 4:114Google Scholar
- 2.Hamilton SR, Aaltonen LA (2000) WHO classification of tumours: pathology and genetics of tumours of the digestive system. International Agency for Research on Cancer, LyonGoogle Scholar
- 11.Song W, Wu SJ, He YL, Cai SR, Zhang CH, Zhang XH, Zhan WH (2009) Clinicopathologic features and survival of patients with mucinous, signet-ring cell or non-mucinous adenocarcinoma: experience at an institution in southern China. Chin Med J (Engl) 122(13):1486–1491Google Scholar
- 19.AJCC (2002) Cancer staging manual, 6th edn. Springer, New YorkGoogle Scholar