Pathologic characteristics of colorectal cancer in the elderly: a retrospective study of 947 surgical cases

Estrogen concentration and estrogen receptor-β expression in postmenopausal colon cancer considering patient/tumor background

PURPOSE

A large number of studies have suggested an inhibitory role of estrogens against colorectal cancer (CRC), but persistent controversy exists. CRC characteristics are affected by sex, age, and tumor locus, suggesting the need for a systematic study considering these factors. The purpose of this study was to verify the difference in the pathobiological role of estrogens in CRC according to patient/tumor backgrounds.

METHODS

Surgical specimens from 116 postmenopausal women (≥ 70 years/o, n = 74; < 70 years/o, n = 42) were studied. Estrogen receptor-β (ER-β), the main ER in the colorectal epithelium, was immunohistochemically examined. The concentrations of estradiol (E2) and estrone (E1) were examined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). These factors were compared according to the tissue type (cancerous or non-cancerous), patients' age, tumor backgrounds (locus, histology, pathological stage, status of mismatch repair protein = MMR), and clinical outcome.

RESULTS

ER-β-positivity, higher E2 concentration, deficient-MMR, and medullary/mucinous histology (Med/Muc) were closely related to right-sided tumors in women who were aged ≥ 70 years /o (R-Ca ≥ 70) and also closely related to each other. ER-β reduction compared with non-cancerous counterparts was observed only in left-sided tumors of patients < 70 years /o (L-Ca < 70), non-Med/Muc, or proficient-MMR tumors.

CONCLUSION

The present results suggest that estrogens do not suppress, but rather promote, R-Ca ≥ 70, Med/Muc, or deficient-MMR tumors, whereas estrogens suppress L-Ca < 70, non-Med/Muc, or proficient-MMR tumors, confirming the difference in pathobiological role of estrogens in postmenopausal colon cancer according to the patients' age and tumor background. This may at least partly explain the controversy regarding the association between estrogens and CRC.

Adjuvant Chemotherapy in Elderly Colorectal Cancer Patients

The value of adjuvant chemotherapy in elderly patients has been the subject of many overviews, with opinions varying from “not effective”, since randomized trials have not been performed, to “as effective as in young individuals”, based upon many retrospective analyses of randomized trials that have included patients of all ages. In the absence of randomized trials performed specifically with elderly patients, retrospective analyses demonstrate that the influence on the time to tumour recurrence (TTR) may be the same as in young individuals, but that endpoints that include death for any reason, such as recurrence-free survival (RFS), disease-free survival (DFS), and overall survival (OS), are poorer in the elderly. This is particularly true if oxaliplatin has been part of the treatment. The need for adjuvant chemotherapy after colorectal cancer surgery in elderly patients is basically the same as that in younger patients. The reduction in recurrence risks may be similar, provided the chosen treatment is tolerated but survival gains are less. Adding oxaliplatin to a fluoropyrimidine is probably not beneficial in individuals above a biological age of approximately 70 years. If an oxaliplatin combination is administered to elderly patients, three months of therapy is in all probability the most realistic goal.

Impact of older age on clinicopathological and prognostic features of colon cancer in postmenopausal women

To clarify the clinicopathological features of colorectal cancer in older people, systematic studies considering age, sex, and the tumor locus is needed. We focused on colon cancer in postmenopausal women (<70 years, n = 68 vs. ≥70 years, n = 85), and examined the effect of age on clinicopathological features. Rates of medullary carcinoma /mucinous carcinoma were higher and pathological stages at diagnosis were less advanced in patients ≥70 years compared with <70 years. Matching pathological stages, no significant difference in disease-free interval was observed according to age; however, disease-specific survival (DSS) was poorer in patients ≥70 years than <70 years, being significantly different in stage IV cases. Regarding post-metastasis/recurrence (met/rec) cases, chemotherapy and surgery for metastasis were less frequent in those aged ≥70 years than <70 years. Post-met/rec DSS was poorer in ≥70 years, those with microsatellite instability, and those without surgery for met/rec than in each counterpart; however, post-met/rec chemotherapy exhibited no effect. Multivariate analyses revealed that an older age and no surgery for metastasis were independent predictors of disease-specific death. These findings remained after excluding stage IV cases. Older age was a potent risk factor of rapid disease-specific death after met/rec.

Surgical outcome and clinicopathological characteristics of emergency presentation elective cases of colorectal cancer

INTRODUCTION

The aim of this study was to evaluate the significance of clinicopathological characteristics of colorectal cancer patients undergoing emergency and elective surgery.

MATERIAL AND METHODS

In total, 116 tumors from patients treated surgically for colorectal cancer at four hospitals in Tehran between 2008 and 2013 were analyzed in the current study.

RESULTS

Our findings revealed that the emergency cases were significantly more likely to have an advanced TNM stage (p = 0.027) and histologic grade (p = 0.01) compared with the elective patients. Furthermore, the nature of surgery was significantly associated with vascular and perineural invasion (p = 0.021; p = 0.001). We also evaluated the association of gender, age, and tumor location with the nature of surgical presentation. However, no association was found between these parameters and the nature of surgery. Emergency was also correlated with greater length of hospital stay and higher rate of admission to the intensive care unit. The mortality rate was 20% in emergency cases, while patients with elective surgery had 5.63% perioperative mortality (p = 0.001). The emergency patients had a higher rate of mortality.

CONCLUSIONS

Our data indicated that colorectal cancer patients undergoing emergency surgery showed an advanced stage. The emergency patients had a higher rate of mortality than elective cases.

Colorectal cancer treatment in octogenarians: elective or emergency surgery?

Background

The purpose of this research was to assess the characteristics of octogenarian patients with colorectal cancer and compare specific outcomes due to different types of surgical procedures used to treat the disease.

Methods

A total of 346 octogenarian patients undergoing surgery for colorectal cancer between April 2000 and April 2010 were retrospectively assessed according to elective (n = 261) or emergent (n = 85) admission group. The two groups were compared for clinical variables, surgical procedures, morbidity and mortality, ICU admission, length of hospital stay and overall survival.

Results

The two groups had similar comorbidities. The emergent group had a more advanced Dukes’ stage, higher American Society of Anesthesiologists grading, lower anastomosis rate (40.2 vs 80.1%), higher stoma rate (30.6 vs 9.6%), more complications (71.8 vs 43.3%), nine days longer length of hospital stay and higher (82.4% vs 36.4%) ICU admission rate. Overall mortality was 9.5%, with a higher mortality rate in the emergent group (30.6%) than the elective group (3.1%).

Conclusions

Octogenarians who undergo elective colorectal cancer surgery have better results than those requiring emergent surgery, but both are quite acceptable and we recommend surgical intervention should not be delayed.

Proximal shift of colorectal cancer along with aging

INTRODUCTION

Although several reports have documented the increased incidence of right-sided colorectal cancer (CRC) in the elderly, especially in women, the gender-specific, age-related changes in the characteristics of CRCs, especially related to the cancer localization, have not been fully investigated. This study evaluated the age-related changes in the clinicopathologic features of CRCs, according to the gender.

MATERIALS AND METHODS

A total of 1059 consecutive patients with CRCs who were admitted to the authors' surgical department between February 2005 and June 2012 were retrospectively reviewed. The patients were divided into male (n = 632) and female (n = 427) groups and then according to the age group, and the correlation between the age group and the other clinicopathologic features was analyzed by univariate and multivariate analysis.

RESULTS

The number of concomitant adenomas found was significantly increased along with increasing age in men, and the presence of concomitant adenoma was the only independent age-related factor of male CRC in the multivariate analysis (P = .0044). In contrast, in women, the location of the CRC progressively shifted to the right side (proximal colon) with increasing age, and the presence of right-sided CRC was the only independent factor of female CRC in the multivariate analysis (P < .0001).

CONCLUSION

There was a significant gender-specific difference in the age-related changes in the characteristics of CRC. Increasing the number of concomitant adenomas and the shift of CRC localization to the proximal colon were the gender-specific characteristics of male and female CRC, respectively.

Deficient HER3 expression in poorly-differentiated colorectal cancer cells enhances gefitinib sensitivity

Poorly-differentiated colorectal cancers (PD-CRC) show high metastatic potential and poor prognosis. However, molecular characteristics of PD-CRC remain unknown to date, particularly in molecular targeting therapy for patients with PD-CRC. In this study, we examined the expression of EGFR, HER2 and HER3 in PD-CRC by immunohistochemical analysis of archived clinical specimens of primary tumors and investigated the sensitivity of PD-CRC cell lines to gefitinib, a tyrosine kinase inhibitor for EGFR in vitro. We found that HER3 expression of PD-CRC among members of the HER family was significantly lower than that of well to moderately differentiated CRC (WMD-CRC) and 37% of the PD cases showed a EGFR+/HER2+/HER3- expression pattern. COLM-5 cells, a PD-CRC-derived cell line, which exhibits EGFR+/HER2+/HER3- expression pattern and recapitulates the typical histology of PD-CRC in xenografted tumors, showed high gefitinib sensitivity both in vitro and in vivo, compared with WMD-CRC cell line (COLM-2). Treatment with gefitinib resulted in the upregulation of p27Kip1 expression and induction of G1 cell cycle arrest, concomitantly associated with inactivation of PI3K/Akt signaling in COLM-5 cells and marked inhibition of xenografted tumors in nude mice, but not evident in COLM-2 cells. Treatment with sodium butyrate, an HDAC inhibitor that induces differentiation, upregulated the expression of HER3 associated with enhancement of the PI3K/Akt signaling, attenuated gefitinib-mediated p27Kip1 upregulation and reduced gefitinib sensitivity in COLM-5 cells in vitro. Furthermore, enforced expression of HER3 in COLM-5 cells resulted in significant resistance to gefitinib treatment both in vitro and in vivo. These findings suggest that deficient HER3 expression plays an important role in gefitinib sensitivity and that a malignant subset of PD with EGFR+/HER2+/HER3- phenotype is a potential candidate for a target of anti-EGFR molecular therapy such as gefitinib.

Role of methylation of the hMLH1 gene promoter in the development of gastric and colorectal carcinoma in the elderly

The occurrence of malignant neoplasms increases with advancing age. Although aging and carcinogenesis are basically different processes, they share phenomena such as the accumulation of DNA damage and abnormal proteins. Recent advances in molecular biology have shown an accumulation of genetic and epigenetic changes in both aging and carcinogenesis, as well as the alteration of metabolism, immunosenescence and shortened telomeres. DNA methylation is a representative epigenetic phenomenon and is frequently involved in controlling gene functions during development and tumorigenesis. We herein focused on methylation of genes in the development of gastrointestinal carcinomas in the elderly. The proportion of gastric and colorectal carcinomas with hypermethylation of the hMLH1 promoter increases with age, reaching 25-30% of all carcinomas of the stomach and large intestine in elderly patients. These tumors have clinicopathological and molecular characteristics such as loss of hMLH1 expression, microsatellite instability, poorly differentiated histology, peritumoral inflammatory cell infiltration, low incidence of lymph node metastasis and favorable prognosis. However, methylation-related carcinogenesis accounts for up to approximately one-third of tumors, and other mechanisms; for example chromosomal instability as a result of telomere dysfunction, are responsible for the development of most carcinomas in the elderly.

Characterization of a novel lymph node metastasis model from human colonic cancer and its preclinical use for comparison of anti-metastatic efficacy between oral S-1 and UFT/ LV

Although lymph node metastasis (LNM) is the most critical prognostic factor in colorectal cancer patients, the anti-LNM efficacy of chemotherapeutic agents is largely unknown because of the limitations of reproducible human colorectal cancer LNM models. Here, we developed a new LNM model from a recently established colorectal cancer cell line (COLM-5) and compared the anti-LNM efficacy of two oral formulations of 5-fluorouracil (5-FU) derivatives, S-1 and UFT/leucovorin (LV). COLM-5 cells is a poorly differentiated adenocarcinoma cell line with unique features such as left-sided, beta-catenin cytoplasmic localization, and microsatellite stable phenotype. COLM-5 cells expressed vascular endothelial growth factor (VEGF-C) and exhibited peritumoral lymphangiogenesis. Consequently, they showed high LNM potential at an incidence of approximately 90% when subcutaneously injected into nude mice, allowing use for preclinical study. When chemotherapy with S-1 or UFT/LV started from the micrometastasis stage, not the advanced macroscopic metastasis stage, anti-LNM efficacy of S-1 was significantly higher than that of UFT/LV at the dosage in which antitumor activity of the two drugs against primary subcutaneous tumor was comparable. COLM-5 cells showed expression pattern of 5-FU metabolizing enzymes such as high dihydropyrimidine dehydrogenase (DPD) and low thymidylate synthase (TS)/orotate phosphoribosyltransferase (OPRT) both in vitro and in vivo. These results suggest that the preferential anti-LNM activity of S-1 compared with UFT/LV against high-DPD COLM-5 tumors is due to the higher DPD inhibitory activity of 5-chloro-2, 4-dihydroxypyrimidine (CDHP) present in S-1 than uracil in UFT. The COLM-5 model would be an excellent tool for understanding the basic mechanism of LNM and for preclinical study on the anti-LNM efficacy of the drugs.

[Implication of late diagnosis for survival of patients with colorectal carcinoma]

BACKGROUND/AIM

Colorectal cancer (CRC) is one of the most frequent diseases and early diagnosis has a potential role to improve survival. The aim of this study was to analyze influence of delay in diagnosis on survival in patiens with colorectal cancer.

METHODS

A total of 119 patients with pathohystological diagnosis of CRC were included in the study. They were operated at our Department for Surgery from 2000 to 2002. They were divided into two groups according to the duration of symptoms: early operated patients - EOP (symptoms were presented for 3 months) and late operated patients - LOP (duration of symptoms was more than 3 months). Follow-up period was 5 year.

RESULTS

Weight loss, intermittent abdominal pain and anorexia were more frequent in LOP (p < 0.01). Young age, blood in stool, and tumor localized in rectum were dominant characteristics in EOP (p < 0.05). Overall delay in diagnosis was 2.19 +/- 0.79 months in EOP and 11.37 +/- 5.68 months in LOP. There was highly statistically significant difference between these two groups (p < 0.01). Overall survival was 44.75%. Five years survival was 65.9% in the group of EOP and 26.5% in the group of LOP (chi2 = 28.16, p < 0.01) Weight loss was dominant characteristics in the patients who did not survive five years (chi2 = 14.26, p < 0.01). A period of 2 months in delay in diagnosis is "cut-off' value in prediction of death (sensitivity of 75.5% and specificity of 90.3%).

CONCLUSION

A delay in diagnosis and stage of the disease are highly significant factors of patients with CRC survival. In everyday medical practice higher importance should be put on weight loss, intermittent abdominal pain, change in bowel habits, as well as on syderopenic anaemia.

Clinicopathological and molecular characteristics of gastric and colorectal carcinomas in the elderly

The occurrence of malignant neoplasms increases with advancing age. Although aging and carcinogenesis are basically different processes, there are phenomena common to each such as accumulation of DNA damage and abnormal proteins. Gastric and colorectal carcinomas are representative tumors in which the prevalence and the number of patients increase significantly with age. Compared with gastric and colorectal cancers occurring in younger patients, those occurring in older patients have clinicopathological differences in tumor location, gender distribution, histological type, histological diversity, multiplicity, incidence of lymph node metastasis, and prognosis. In the elderly there are peculiar types of carcinoma such as medullary-type poorly differentiated colorectal adenocarcinoma and solid-type poorly differentiated gastric adenocarcinoma, both of which occur in older women. Methylation, apoptosis, and telomere dysfunction play important roles in the development of gastric and colorectal cancers in the elderly.

Microsatellite-unstable mucinous colorectal carcinoma occurring in the elderly: comparison with medullary type poorly differentiated adenocarcinoma

Mucinous carcinoma and poorly differentiated adenocarcinoma of the large intestine have a high frequency of microsatellite instability, and their occurrence increases gradually with age. To elucidate the clinicopathological and immunohistochemical features of microsatellite-unstable mucinous carcinoma and compare the tumor with medullary type poorly differentiated adenocarcinoma, the clinicopathological status and expression of mucin core and hMLH1 proteins were studied in 15 microsatellite-unstable and 20 microsatellite-stable mucinous colorectal carcinomas occurring in elderly patients, and compared with 23 cases of medullary type poorly differentiated adenocarcinoma in which 21 cases were microsatellite-unstable. Thirteen (87%) of 15 microsatellite-unstable carcinomas exhibited absent hMLH1 expression compared with three (15%) of 20 microsatellite-stable carcinomas (P < 0.01). The proportion (87%) of positive MUC5AC expression in microsatellite-unstable mucinous carcinoma was significantly higher than that (45%) in microsatellite-stable mucinous carcinoma (P = 0.01). Compared with microsatellite-stable mucinous carcinoma, microsatellite-unstable mucinous carcinomas were significantly associated with a proximal location, intra- and peritumoral inflammatory cell infiltration, frequent MUC5AC expression, a low incidence of lymph node metastasis and absent hMLH1 protein expression, which is not different to medullary type poorly differentiated adenocarcinoma except for MUC2 expression and age-related occurrence. These results suggest that microsatellite-unstable mucinous carcinoma occurring in the elderly shares clinicopathological and molecular features with medullary type poorly differentiated adenocarcinoma and that microsatellite instability with absent hMLH1 expression plays an important role in the development of these two carcinomas.

Age-related alteration in the association of microsatellite instability with absent hMLH1 expression and histological types of colorectal carcinoma

Microsatellite instability (MSI) is present in approximately 15-20% of sporadic colorectal cancers. However, despite the increased prevalence of absent hMLH1 expression and MSI in colorectal cancer in the elderly, few attempts have been made to define it in detail. The aim of the present paper was to correlate age-related alterations in absent hMLH1 expression and MSI with various histological types of colorectal carcinoma. hMLH1 expression and microsatellite status were studied in 184 colorectal carcinomas (49 well-differentiated, 49 moderately differentiated, 49 poorly differentiated adenocarcinomas, and 37 mucinous carcinomas). The prevalence of absent hMLH1 expression was higher in poorly differentiated adenocarcinoma (63%) and mucinous carcinoma (43%) than in well- (8%) and moderately (12%) differentiated adenocarcinomas. MSI was found more frequently in poorly differentiated adenocarcinoma (69%) and mucinous carcinoma (41%) than in well- and moderately differentiated adenocarcinomas (8% and 6%, respectively). Age-related differences in absent hMLH1 expression and MSI were found only in poorly differentiated adenocarcinoma, in which the prevalence of medullary-type carcinoma increased with advancing age. These results indicate that an age-related increase of medullary-type tumors in poorly differentiated adenocarcinoma may play an important role in the increase of absent hMLH1 expression and MSI in colorectal carcinoma.

The impact of age on post-operative outcomes of colorectal cancer patients undergoing surgical treatment

Background

the purpose of study was to evaluate the impact of age on outcomes in colorectal cancer surgery.

Methods

patients on hospital database treated for colorectal cancer during the period 1995 – 2002 were divided into two groups: Group 1 – patients of 75 years or older (n = 154), and Group 2 – those younger than 75 years (n = 532).

Results

In Group 1, for colon cancers, proximal tumors were significantly more common (23% vs. 13.5%, p < 0.05), complicated cases were more frequent (46 % vs. 33%, p = 0.002), bowel obstruction more common at presentation (40% vs. 26.5%, p = 0.001), and more frequent emergency surgery required (24% vs. 14%, p = 0.003). Postoperative overall morbidity was higher in the elderly group, but with no differences in surgical complications rate. Overall 5 year survival was 39% vs. 55% (p = 0.0006) and cancer related 5 year survival was 44% vs. 62% (p = 0.0006). Multivariate Cox analysis showed that age was not an independent risk factor for postoperative mortality.

Conclusion

Preoperative complications and co-morbidities, more advanced disease, and higher postoperative nonsurgical complication rates adversely affect postoperative outcomes after surgery for colorectal cancer in the elderly.

The impact of the risk factor "age" on the early postoperative results of surgery for colorectal carcinoma and its significance for perioperative management

The risks and benefits of surgery for colorectal cancer in old patients have not been unequivocally defined. The present investigation was carried out in 309 hospitals as a prospective multicenter study. In the period between 1 January 2000 and 31 December 2001, a total of 19,080 patients were recruited for the study; 16,142 (84.6%) patients were younger than 80 years (<80) and 2932 (15.4%) were 80 years and older (> or =80). Significant differences between the age groups were observed for general postoperative complications (22.3% for <80 years; 33.9% for > or =80). Specific postoperative complications were identical in both groups. Overall, significantly elevated morbidity and mortality rates were found with increasing age (morbidity: 33.9% vs. 43.5%; mortality: 2.6% vs. 8.0%). The distribution of tumor stages revealed a significantly higher percentage of locally advanced tumors in the older age group (stage II: 28.0% vs. 34.4%). In contrast, no increase in metastasizing tumors was found in the older age group (stage IV: 17.4% vs. 14.1%). Logistic regression showed that, in concert with a number of other parameters, age is a significant influencing factor on postoperative morbidity and mortality. The increase in postoperative morbidity and mortality rates associated with aging is a result of the increase in general postoperative complications, in particular, pneumonia and cardiovascular complications. Age as such does not represent a contraindication for surgical treatment. The short-term outcome and quality of life are of overriding importance for the geriatric patient.

Cancer and aging: symposium of the 27th annual meeting of the Japanese society for biomedical gerontology, Tokyo

Although many hypotheses have been proposed to explain the strong link between aging and cancer, the exact mechanisms responsible for the increased frequency of occurrence of cancer with advancing age have not been fully defined. Recent evidence indicates that malregulation of the apoptotic process may be involved in some aging process as well as in the development of cancer. Although it is still under debate how apoptosis is expressed during aging in vivo, this phenomenon is an important factor in unwinding the complicated mechanisms that link cancer and aging. In this review, we report on the discussion at the symposium of the 27th annual meeting of the Japanese society for biomedical gerontology, regarding recent findings from aging and carcinogenesis studies using animal models, the characteristics of cancer in patients with Werner's syndrome, the epigenetic changes in human cancers and aging, and the characteristics of human cancers in the elderly. It was concluded that apoptosis plays a role in the aging process and carcinogenesis in vivo, likely as an inherent protective mechanism against various kinds of damages to genes/chromosomes.

Expression level of Wnt signaling components possibly influences the biological behavior of colorectal cancer in different age groups

Advancing of age apparently influences the behavior of colorectal cancer (CRC). The pattern of activation and expression of Wnt target genes may influence the behavior of the cancer. In the present study, the level of activation of some elements of Wnt signaling was evaluated and correlated with the patient's age and clinicopathological characteristics of the tumor. Beta-catenin and c-Myc mRNA expressions were evaluated by semiquantitative real-time PCR, and subcellular localization of the beta-catenin protein was evaluated by immunohistochemistry. Patients aged 70-84 tended to have locally advanced disease more frequently than younger patients. The same group of patients also more frequently had high nuclear expression of beta-catenin protein and higher expression of c-Myc mRNA. Beta-catenin mRNA had a rather constant expression with advancing of age. High nuclear expression of beta-catenin and high expression of c-Myc were apparently also correlated with locally advanced disease. We concluded that the level of Wnt signaling activation might influence the behavior of the disease in different age groups.

Should patients over 85 years old be operated on for colorectal cancer?

BACKGROUND

The aim of this study is to evaluate risk factors for mortality, morbidity, and long-term survival in very old patients with colorectal cancer compared with old patients.

METHODS

Patients operated on with colorectal cancer aged 75 years old or older were divided into 2 groups: Group A (75-84 years, n = 93) and Group B (>or=85, n = 21).

RESULTS

The serum albumin level, oxygen pressure in arterial blood gases, and forced expiratory volume in 1 second in Group B were significantly lower than in Group A, respectively (P = 0.0094, 0.0264, 0.0363). Pulmonary complications were developed significantly more frequently in Group B than in Group A (P = 0.0019). Group B had a significantly higher mortality rate than Group A (P = 0.0477). There was no significant difference between the 2 groups in the 2- and 5-year survival rates.

CONCLUSIONS

Very old patients with colorectal cancer should not be denied surgery on account of chronological age alone, although the perioperative risks for the very old are very high.

Hypermethylation of the hMLH1 promoter with absent hMLH1 expression in medullary-type poorly differentiated colorectal adenocarcinoma in the elderly

To clarify the significance of hMLH1 promoter hypermethylation in the development of medullary-type poorly differentiated colorectal adenocarcinoma, we studied the status of promoter methylation and hMLH1 expression in 23 medullary-type and 12 pleomorphic-type carcinomas, as well as the pathology and microsatellite status. In medullary-type carcinomas, the percentages of cases with promoter methylation (83%) and an absence of hMLH1 expression (91%) were significantly higher than in pleomorphic-type carcinomas (14 and 17%), respectively. The rate of microsatellite instability in the medullary type was significantly higher than that of the pleomorphic type (87 vs 40%, P<0.01). Compared with pleomorphic-type carcinomas, medullary-type carcinomas were significantly associated with hMLH1 promoter methylation, absent expression of hMLH1 protein, microsatellite instability, as well as a proximal location, a Crohn's-like lymphoid reaction, a low incidence of lymph node metastasis, and a favorable outcome. Medullary-type carcinomas accumulated with advancing age, especially in the female. These results indicated that hMLH1 hypermethylation, concurrent with a lack of its protein expression, may play an important role in the development of medullary-type poorly differentiated colorectal adenocarcinomas in the elderly.

N/A

N/A

Poor prognosis of colorectal cancer in patients over 80 years old is associated with down-regulation of tumor suppressor genes

GOALS, BACKGROUND: The elderly population has been increasing during the last half a century and it would be important to know how aging influences the occurrence and biologic behavior of cancers.

STUDY

We investigated clinicopathologic characteristics of colorectal cancer in 1354 patients who underwent colorectal cancer resection and compared the results between extremely elderly patients (over 80 years old) and middle-aged/elderly patients (40 to less than 80 years old). Furthermore, we also examined expression of tumor suppressor genes and Cox-2 using frozen samples of colorectal cancer obtained from 62 patients ranging in age from 45 to 87 years.

RESULTS

The results obtained in the extremely aged patients were: (1) higher ratio of women, (2) higher incidence at the proximal site, (3) higher incidence of cases with deeper invasion, (4) higher incidence of cases with lymph node metastasis (5) poorer survival rate as compared with middle-aged/elderly patients, and (6) lower mRNA expression levels of p27 and p53.

CONCLUSIONS

These findings taken together suggest that poor prognosis of colorectal cancer in patients over 80 years is associated with down-regulation of mRNA expression of some tumor suppressor genes.

Incidence of apoptosis increases with age in colorectal cancer

The incidence of cancer increases with advancing age, but the biological behavior of cancer is known to be less aggressive in elderly people. Thus, the proliferative activity and extent of apoptosis of cancer cells were assessed in samples from 163 cases of colorectal cancer focusing on the age of patients, using Ki-67 labeling index (LI) and apoptotic index (AI) by terminal deoxynucleotidyl transferase (TdT)-mediated d-UTP nick end labeling method and staining for activated caspase-3. The Ki-67 LI of colorectal cancer ranged from 2.33 to 80.4% (mean 32.2%), while the AI ranged from 0.00 to 14.8% (mean 3.57%). Concerning the aging effect, linear and positive correlations were found for the Ki-67 LI of cancer with age (p<0.05) and the AI of cancer with age (p<0.05). However, in normal colorectal mucosa, aging of patients revealed a significant correlation only with the AI but not with the Ki-67 LI. The AI in earlier stages of cancers (stages 0 and 1) revealed a significant difference between younger cases (age<65) and more elderly cases (age>/=65) (p<0.05), however, the Ki-67 LI did not exhibit a significant difference. Therefore, an increased frequency of apoptosis in colorectal cancer tissues, especially in the earlier stages, may possibly explain the slower growth of colorectal cancers in the elderly. Next, the expressions of several regulatory molecules for the proliferation/apoptosis of tumor cells were determined. The results demonstrated a tendency for stronger and more frequent expressions of c-myc, Bak and Bax despite a rather weaker expression of Bcl-2 in cancer tissues from the elderly compared with those from the younger patients. The potential roles of these regulatory molecules on age-change in the proliferation/apoptosis of colorectal cancers are discussed.

Major colorectal cancer resection should not be denied to the elderly

AIMS

Adjuvant therapy after surgery for colorectal cancer is often denied to the elderly for various reasons. This study was to determine morbidity and mortality risk after surgery in the elderly and whether this is affected by adjuvant therapy.

METHODS

Data were collected prospectively and entered on a database for all patients undergoing resection of colorectal cancer between January 1994 and July 2000. A total of 304 patients were included, 65 aged 80 years and over.

RESULTS

There were 84 deaths, 21 (30%) in the over 80s, and 63 (26%) in the under 80s (P=0.51). The 'in-hospital' mortality was 10.1% in the over 80s and 3.8% in the under 80s (P=0.056). In the over 80s the colon was more affected than the rectum (P=0.002). The over 80s were less likely to be offered adjuvant therapy, 7.2% vs 42.1% (P<0.001). The 5 year survival (all-cause mortality) in the over 80s was 58.5% and 47.6% in the under 80s (P=0.25). Cox's regression analysis of all patients identified the following factors to be independently related to overall survival: age>80 years, post-operative leak, increasing Dukes stage and distant recurrence of disease.

CONCLUSION

This study has demonstrated that surgery should not be denied to elderly patients with colorectal cancer as despite a higher post-operative morbidity and mortality rate and with the absence of adjuvant therapy, favourable long-term outcome can be achieved by resectional surgery alone.

Surgical pathology of colorectal cancer in Filipinos: implications for clinical practice

BACKGROUND

A number of studies published in the Philippine literature have demonstrated certain peculiar clinicopathologic characteristics of colorectal cancer among Filipinos. This study presents the latest data and analyzes their implications for clinical practice.

STUDY DESIGN

The pathology reports of all patients who underwent operation for colorectal cancer at the Philippine General Hospital over a period of 7 years were reviewed.

RESULTS

One thousand two hundred seventy-seven patients were included. The male to female ratio was almost 1:1. The majority of patients were in the sixth and seventh decades of life, with a mean age of 55.3 years. Patients 40 years of age and younger made up 17% of the total. The site of cancer in order of frequency was rectum (49.8%), left colon (27.9%), and right colon (21.4%). Cancers of the right colon were more common in women, and rectal cancers were more frequent in men. Seventy-six percent of the tumors were well to moderately differentiated adenocarcinomas, and 6.7% were poorly differentiated. Mucinous and signet ring carcinomas were found in 11% and 1% of cases, respectively. Forty-four percent of patients had localized disease at the time of operation, 54% had regional disease, and 2% had disseminated disease. Associated predisposing conditions noted were polyps (4.7%), schistosomiasis (3%), and tuberculosis (1.5%).

CONCLUSIONS

Colorectal cancer in Filipinos exhibits a number of unique clinicopathologic features, such as a higher proportion of early age of onset tumors, more advanced stage at presentation, an association with chronic granulomatous diseases, and relatively rare occurrence with polyps. This might suggest the possibility of a different pathway for tumor development of colorectal cancer in this population of patients. Also, current screening guidelines advocated for the Western population might not be appropriate for Filipinos.