PubMed Health⌕ Search

Biomedical subjects

Shomik Sengupta

Publications and source records attributed to Shomik Sengupta.

At least 19 recordsLinked to original sources
PubMed2007

Early effects of pharmacological androgen deprivation in human prostate cancer.

OBJECTIVES: To assess the early histological effects of pharmacological androgen deprivation (AD), which have been assessed only over longer periods, as surgical castration leads rapidly to diminished cell proliferation and enhanced cell death within the prostate. PATIENTS AND METHODS: With Institutional Review Board approval, 35 patients were randomly assigned (seven in each group) to receive 0, 7, 14, 21 and 28 days of AD (flutamide, 250 mg orally three times/day, and one injection with leuprolide acetate 7.5 mg) before radical prostatectomy. The surgical specimens were assessed by conventional histology and immunohistochemistry, while macroarray analysis and quantitative real-time polymerase chain reaction (QRT-PCR) were used to examine gene expression. RESULTS: There were morphological changes within the prostatic tissues as early as 7 days after initiating AD, similar to the response to castration. There was tumour cell vacuolization indicating cellular injury, glandular atrophy and mononuclear cell infiltration as prominent and progressive effects but, by contrast with castration studies, there were no changes in epithelial proliferation or apoptosis. Macroarray analysis, validated by QRT-PCR and immunohistochemistry, showed up-regulation of numerous and potentially counter-effective genes involved in the cell cycle and apoptosis. CONCLUSIONS: Pharmacological AD induces significant involution within prostatic tissues over 7-28 days, but allows the persistence of some viable tumour cells capable of proliferation.

Adenocarcinoma↗
PubMed2006

Obesity and survival after radical prostatectomy: A 10-year prospective cohort study.

BACKGROUND: Obesity and prostate cancer are among the most common health problems affecting American men today. The authors' goal was to assess the impact of obesity on clinical and pathologic features of prostate cancer and long-term outcomes. METHODS: The authors performed a prospective cohort study on 5313 men who underwent radical prostatectomy between 1990 and 1999. Patient height and weight were measured at the time of surgery to calculate the body mass index (BMI). The patients were separated into 3 BMI groups: BMI <25, 25-29.9, and > or =30 kg/m2. The associations between BMI and age, prostate-specific antigen (PSA) level, and Gleason score were assessed with the Spearman rank correlation test. The associations between BMI and pathologic features were assessed with the Mantel-Haenszel chi 2 test. Fifteen-year biochemical progression-free survival, systemic progression-free survival, cancer-specific survival, and overall survival were estimated using the Kaplan-Meier method and evaluated using Cox models. RESULTS.: The median length of follow-up for the entire cohort was 10.1 years. Clinical and pathologic features appear worse in patients with a higher BMI. On univariate and multivariate analyses, it was found that BMI had no impact on biochemical progression, systemic progression, prostate cancer survival, or overall survival. CONCLUSIONS: Obese patients appear to have worse pathologic features at the time of prostatectomy. Despite these features, long-term oncologic outcomes, including cancer-specific survival, remain the same regardless of BMI. BMI appears to influence prostate cancer outcomes at the time of prostatectomy, as evidenced by more aggressive pathologic features. However, after prostatectomy, BMI does not appear to be an independent predictor of recurrence or survival.

Age Factors↗
PubMed2006

Mononuclear cell infiltration in clear-cell renal cell carcinoma independently predicts patient survival.

BACKGROUND: The impact of mononuclear cell infiltration on renal cell carcinoma (RCC) biology has been controversial, previously reported to be associated with either a favorable or unfavorable prognosis. The objective of the current study was to evaluate associations between mononuclear cell infiltration in routinely prepared paraffin-embedded specimens with survival in patients with clear-cell RCC. METHODS: A total of 306 patients were identified treated with nephrectomy for clear-cell RCC between 1990 and 1994. A single urologic pathologist, blinded to patient outcome, reviewed the specimens and quantified the extent of mononuclear cell infiltration as absent, focal, moderate, or marked. Cancer-specific survival was estimated using the Kaplan-Meier method. Associations of mononuclear cell infiltration with death from RCC were assessed using Cox proportional hazards regression models. RESULTS: At last follow-up, 173 of the 306 patients studied had died, including 96 patients who died from RCC. Mononuclear cell infiltration was absent in 165 (54%), focal in 70 (23%), moderate in 53 (17%), and marked in 18 (6%). Univariately, patients with specimens that had mononuclear cell infiltration were over 2 times more likely to die from RCC compared with patients whose specimens exhibited no mononuclear cell infiltration (risk ratio, 2.63; P < .001). After adjusting for the Mayo Clinic SSIGN (stage, size, grade, and necrosis) score, patients with specimens that had mononuclear cell infiltration exhibited a significantly increased likelihood of dying from RCC compared with patients whose specimens had no mononuclear cell infiltration (risk ratio, 1.61; P = .028). CONCLUSIONS: Mononuclear cell infiltration is associated with death from RCC even after multivariate adjustment. Routine documentation of mononuclear cell infiltration is recommended during the pathologic assessment of RCC.

Carcinoma, Renal Cell↗
PubMed2006

Trends in distribution and prognostic significance of Gleason grades on radical retropubic prostatectomy specimens between 1989 and 2001.

BACKGROUND: The objectives of the current study were to examine time trends in the prevalence of Gleason grades of prostate cancer on radical retropubic prostatectomy (RRP) specimens and to assess the resultant impact on prognosis. METHODS: The authors examined the prevalence over time of each grade and Gleason score (GS) on RRP specimens from 8750 patients who were treated between 1989 and 2001. Biochemical recurrence-free survival (BRFS), which was estimated by using Kaplan-Meier methodology, was examined in subgroups of patients defined by tumor grade and era of surgery. RESULTS: The prevalence of Grade 3 prostate cancers increased (86% vs. 49% for primary Gleason grade and 71% vs. 47% for secondary Gleason grade; 1999-2001 vs. 1989-1990, respectively), whereas the prevalence of Grade 2 tumors decreased (0.4% vs. 38% for primary Gleason grade and 1.3% vs. 28% for secondary Gleason grade, respectively) over the study period, leading to fewer GS 4 and 5 tumors and more GS 6 and 7 tumors. BRFS improved over time for patients who had GS 5 tumors (hazards ratio [HR], 0.92 per year; P = .003) and GS 6 tumors (HR, 0.93; P < .001) but remained unchanged for GS 7 tumors (HR 0.99; P = .462) and GS 8-10 tumors (HR 1.02; P = .360). Patients who were treated in the recent era (1997-2001) had greater differentiation of BRFS based on GS or Gleason grade compared with patients who were treated earlier (1989-1991). CONCLUSIONS: The current results confirmed that there were changes in the prevalence of Gleason grades on RRP specimens between 1989 and 2001. A chronological change in pathologic grading classification is suggested by evolving prognostic implications, which must be accounted for when comparing outcomes from different eras.

Adult↗
PubMed2006

Tumor B7-H1 is associated with poor prognosis in renal cell carcinoma patients with long-term follow-up.

B7-H1 participates in T-cell costimulation functioning as a negative regulator of immunity. Recent observations suggest that B7-H1 is expressed by renal cell carcinoma (RCC) tumor cells and is associated with poor prognosis. However, outcome analyses have been restricted to patients with fresh-frozen tissue and limited follow-up. We report the clinical effect of B7-H1 in RCC patients with a median of 10 years of follow-up. Between 1990 and 1994, 306 patients underwent nephrectomy for clear cell RCC and had paraffin tissue available for review. We did immunohistochemistry with anti-B7-H1 and conducted outcome analyses. Among the 306 patients, 73 (23.9%) harbored tumors with B7-H1 expression. Patients with tumor B7-H1 were at a significantly increased risk of both death from RCC [risk ratio (RR), 3.92; P < 0.001] and overall mortality (RR, 2.37; P < 0.001). The 5-year cancer-specific survival rates were 41.9% and 82.9% for patients with and without tumor B7-H1, respectively. In a multivariate model, tumor B7-H1 remained associated with cancer-specific death even after adjusting for tumor-node-metastasis stage, grade, and performance status (RR, 2.00; P = 0.003). In the subset of 268 patients with localized RCC, tumor B7-H1 was significantly associated with metastatic cancer progression (RR, 3.46; P < 0.001) and death from RCC (RR, 4.13; P < 0.001) even after adjusting for stage, grade, and performance status (RR, 1.78, P = 0.036). RCC patients with tumor B7-H1 are at significant risk of rapid cancer progression and accelerated rates of mortality. B7-H1 may function as a key determinant in RCC, abrogating immune responses directed against this immunogenic tumor.

Antigens, CD↗
PubMed2006

The preoperative erythrocyte sedimentation rate is an independent prognostic factor in renal cell carcinoma.

BACKGROUND: Prognostic nomograms are used increasingly in clinical trials and to guide surveillance for patients with renal cell carcinoma (RCC). An elevated erythrocyte sedimentation rate (ESR) reportedly has been associated with a poor prognosis among patients with RCC, but the ESR is not incorporated into existing nomograms. Hence, the current study was conducted to expand on prior observations pertaining to the ESR as a prognostic indicator in patients with RCC. METHODS: The authors identified 3008 patients who underwent nephrectomy for RCC between 1970 and 2002. Disease-specific survival was estimated using the Kaplan-Meier method, and its association with the ESR and other clinical and pathologic features was evaluated using Cox proportional hazards regression analysis. RESULTS: A preoperative ESR was available for 1075 patients (35.7%), 501 of whom (46.6%) exhibited an elevated ESR, including 437 of 881 patients (49.2%) with clear cell RCC, 41 of 134 patients (30.6%) with papillary RCC, and 20 of 48 patients (41.7%) with chromophobe RCC. An elevated ESR was associated with adverse clinical, laboratory, and pathologic profiles for all three histologic subtypes. The risk ratios (RRs) and 95% confidence intervals (95% CIs) for death because of clear cell RCC, papillary RCC, and chromophobe RCC for patients with an elevated ESR were 3.6 (95% CI, 1.1-1.9), 3.8 (95% CI, 1.4-10.6), and 10.3 (95% CI, 1.2-89.5), respectively. The association between an elevated ESR and death from clear cell RCC persisted even after multivariate analysis (RR of 1.5; 95% CI, 1.2-2.0). CONCLUSIONS: An elevated ESR in patients with RCC suggested the presence of aggressive disease and poorer outcomes after surgical treatment. For patients with clear cell RCC, the ESR provided useful information above and beyond traditional prognostic algorithms, and it may be valuable for preoperative prognostication.

Adult↗
PubMed2006

Detectable prostate specific antigen between 60 and 120 days following radical prostatectomy for prostate cancer: natural history and prognostic significance.

PURPOSE: Following radical retropubic prostatectomy for prostate cancer, if the serum prostate specific antigen fails to become undetectable, occult micrometastatic disease is suspected. We assessed the natural history of disease progression, and predictors of recurrence and survival in this group of patients. MATERIALS AND METHODS: We identified 303 men treated with radical retropubic prostatectomy for prostate cancer between 1990 and 1999, who had a detectable prostate specific antigen between 60 and 120 days postoperatively. Systemic recurrence-free and cancer specific survival were estimated using the Kaplan-Meier method, and analyzed using Cox proportional hazards models. RESULTS: Clinical and pathological features were more adverse among men whose postoperative prostate specific antigen was detectable. These men had poorer systemic recurrence-free survival and cancer specific survival compared to men with an undetectable postoperative prostate specific antigen, and even men whose prostate specific antigen subsequently became detectable. These differences persisted after multivariate adjustment for preoperative prostate specific antigen, specimen Gleason score, seminal vesicle and margin status. With a median followup of 8.5 years, 50 systemic recurrences and 26 deaths from cancer were observed. Gleason score and the prostate specific antigen doubling time were multivariate predictors of systemic recurrence, while Gleason score, margin status and seminal vesicle invasion were predictors of death from cancer. CONCLUSIONS: A detectable prostate specific antigen immediately following radical retropubic prostatectomy confers an increased risk of progression and death, but only in a subset of patients, who may be identified on the basis of pathological features and prostate specific antigen doubling time. In future such patients may be suitable for trials of systemic therapy.

Adult↗
PubMed2006

Impact of familial and hereditary prostate cancer on cancer specific survival after radical retropubic prostatectomy.

PURPOSE: Men with a family history of prostate cancer are at higher risk for prostate cancer. There are conflicting data regarding the impact of hereditary forms of prostate cancer on long-term outcomes after radical prostatectomy. We examined the impact of familial and hereditary prostate cancer treatment in the prostate specific antigen era. MATERIALS AND METHODS: Patients who underwent radical prostatectomy for prostate cancer from 1987 to 1997 were surveyed (3,560 responders) to determine the family history of prostate cancer. Patients were categorized as having familial prostate cancer if they had at least 1 first-degree relative with prostate cancer. Hereditary prostate cancer was defined as nuclear families with 3 cases of prostate cancer, families with prostate cancer in each of 3 generations and families with 2 men diagnosed before age 55 years. Sporadic prostate cancer was defined as patients with no family history. Clinical and pathological features, and long-term outcome measures, including biochemical recurrence-free, systemic progression-free and cancer specific survival, were compared among patients with familial, hereditary and sporadic prostate cancer. RESULTS: A total of 865 and 133 patients were categorized as having familial prostate cancer and hereditary prostate cancer, respectively. Preoperatively prostate specific antigen was higher in patients with hereditary prostate cancer than in the other 2 groups (p = 0.04). Ten-year biochemical progression-free, systemic progression-free and cancer specific survival were equivalent. CONCLUSIONS: Except for preoperative prostate specific antigen, clinicopathological features and long-term oncological outcomes are equivalent after radical prostatectomy in patients with familial, hereditary and sporadic prostate cancer.

Adult↗
PubMed2006

Simple graphic method for estimation of prostate-specific antigen doubling time.

The prostate-specific antigen doubling time (PSADT) is of prognostic value in patients with prostate cancer, but computerized algorithms are usually required for PSADT estimation. We present here a simple graphic tool that can be used to estimate the PSADT on the basis of two increasing PSA measurements, separated by 3 to 12 months.

Humans↗
PubMed2006

The management of superficial transitional cell carcinoma of the bladder.

Superficial transitional cell carcinomas (TCC) of the urinary bladder, defined as those that are restricted to the mucosa or the lamina propria, represent a common condition with a wide spectrum of biologic significance. High-grade superficial TCC, particularly in the presence of lamina propria invasion, has a significant risk of occult or subsequent progression to muscle-invasive or metastatic disease. Such high-risk lesions merit aggressive therapy with repeat resection followed by intravesical therapy, usually in the form of bacille Calmette-Guérin. Criteria for failure of intravesical therapy are not well defined, but persistent cytologic or cystoscopic abnormalities at 6 months are worrisome. Salvage intravesical therapy may sometimes be successful, but early cystectomy should be strongly considered, especially in younger patients. Close surveillance of patients with high-risk superficial TCC is essential.

Carcinoma, Transitional Cell↗
PubMed2006

Conventional assessment of needle biopsy specimens is more useful than digital image analysis of proliferation and DNA ploidy in prediction of positive surgical margins at radical prostatectomy.

OBJECTIVES: The preoperative prediction of the likelihood of positive surgical margins (+SMs) at radical retropubic prostatectomy (RRP) may be useful for counseling and determining the surgical approach. The aim of this study was to assess the additional value of digital image analysis (DIA) of ploidy and proliferation on needle biopsies, in addition to the known preoperative predictors of +SMs at RRP. METHODS: We identified 454 patients treated by RRP at our institution from 1995 to 1998 for prostate cancer verified by transrectal ultrasound-guided biopsy, with a specimen adequate for DIA. Patients receiving preoperative hormonal therapy were excluded. The clinical features, transrectal ultrasound-guided biopsy findings, and DIA evaluation of MIB-I immunostaining and DNA ploidy were assessed in a multivariate logistic regression model to predict for +SMs at RRP. RESULTS: The mean +/- SD age at treatment was 64.5 +/- 6.5 years, the percentage of positive cores was 40.4% +/- 24.3%, the median prostate-specific antigen level was 6.3 ng/mL (range 0.6 to 112.0), median biopsy Gleason score was 6 (range 4 to 9), and median percentage of diploid nuclei was 67% (range 0% to 100%). Of the 454 patients, 185 (40.7%) had +SMs; this finding was time dependent (1995 to 1996, 45% and 1997 to 1998, 31%; P = 0.004). Univariately, preoperative prostate-specific antigen, biopsy Gleason score, extent of cancer on biopsy, MIB-1 expression, percentage of diploid or nondiploid nuclei, and year of surgery were predictive for +SMs. On multivariate analysis, the preoperative prostate-specific antigen level, biopsy Gleason score, percentage of positive cores, and year of surgery remained significant. CONCLUSIONS: The results of our study have shown that the likelihood of +SMs at RRP is best predicted on the basis of conventional prognostic factors. The DIA features of needle biopsies did not provide additional predictive power.

Adult↗
PubMed2006

Permanent prostate brachytherapy: pathologic implications as assessed on radical prostatectomy specimens of broadening selection criteria for monotherapy.

OBJECTIVES: To assess the impact of clinical selection criteria on pathologic features among patients treated by radical retropubic prostatectomy and to evaluate the implications of broadening eligibility for permanent prostate brachytherapy monotherapy. METHODS: A consecutive series of 423 patients with prostate cancer, who underwent diagnostic biopsy and subsequent radical retropubic prostatectomy, were selected for this study. Four subgroups were defined using the American Brachytherapy Society selection criteria, including prostate size limits (group 1), no prostate size limits (group 2A), a modified set of criteria (group 2B), and clinical Stage T1-T2 (group 3). The rates of extraprostatic extension, seminal vesicle invasion, and lymph node involvement were compared. RESULTS: Adverse pathologic features at radical retropubic prostatectomy were noted in 8 (9.3%) of 86 patients in group 1, 11 (5.6%) of 195 patients in group 2A, 35 (12.0%) of 292 patients in group 2B, and 90 (21.8%) of 413 patients in group 3. The rates of extraprostatic extension, seminal vesicle invasion, and lymph node involvement appeared comparable among groups 1 (5.8%, 3.5%, and 0.0%, respectively), 2A (3.6%, 2.1%, and 0.0%, respectively), and 2B (6.9%, 3.8%, and 1.4%, respectively), but were greater in group 3 (9.7%, 7.8%, and 4.4%, respectively). CONCLUSIONS: Judicious broadening of the clinical selection criteria may allow a greater number of patients to be eligible for permanent prostate brachytherapy monotherapy by including patients whose risk of having adverse pathologic features is comparable to that of patients currently deemed suitable for permanent prostate brachytherapy monotherapy. Prospective assessment of oncologic outcomes of such an approach is required.

Adult↗
PubMed2006

Rare expression of KIT and absence of KIT mutations in high grade renal cell carcinoma.

PURPOSE: RCCs with sarcomatoid differentiation have been reported to frequently express KIT protein, suggesting that imatinib mesylate (STI-571 or Gleevectrade mark) may be effective treatment for these aggressive tumors. We determined the frequency of KIT expression and mutation in a large series of high grade RCCs. MATERIALS AND METHODS: We identified 194 patients who underwent nephrectomy for unilateral, sporadic nuclear grade 4 RCC between 1970 and 2002, including 123 with sarcomatoid differentiation. Sections from representative paraffin embedded tissue blocks were immunostained in an autostainer using ethylenediaminetetraacetic acid antigen retrieval, a polyclonal KIT antibody and the avidin-biotin peroxidase complex method. Mutational analysis was performed in all immunopositive and select negative cases by polymerase chain reaction amplification of KIT exons 9, 11, 13 and 17. RESULTS: Only 7 tumors (3.6%) showed KIT expression, including 5 of the 123 (4.1%) with sarcomatoid differentiation. Four of the 7 tumors showed focal staining only. No mutations were identified in the 7 positive cases or in 8 randomly selected negative samples. Death from RCC occurred in all 7 patients with KIT positive tumors at a median of 0.6 years (range 0.3 to 2.3) and in 139 of 187 with KIT negative tumors at a median of 0.8 years (range 0 to 10.2). CONCLUSIONS: KIT expression was identified in less than 5% of high grade RCCs with or without sarcomatoid differentiation but none of the tumors showed KIT mutations. These findings indicate that imatinib therapy is unlikely to be effective in patients with high grade RCC.

Carcinoma, Renal Cell↗
PubMed2006

Impact of patient age at treatment on outcome following radical retropubic prostatectomy for prostate cancer.

PURPOSE: Historically young patients with prostate cancer have been found to have poorer outcomes. Recent studies suggest favorable pathological findings and improved survival in younger patients undergoing RRP. We assessed age at treatment as a predictor of post-RRP survival. MATERIALS AND METHODS: We identified 5,509 patients treated with RRP for prostate cancer at our institution between 1987 and 1995. Age at treatment was classified into categories of younger than 55, 55 to 59, 60 to 64, 65 to 69 and 70 years or older. CSS, sPFS and biochemical PFS were estimated by the Kaplan-Meier method and analyzed using Cox proportional hazard models. RESULTS: Younger patients had lower preoperative prostate specific antigen, and tumor grade and stage. CSS, sPFS and biochemical PFS were similar across age groups but overall survival decreased with older age at treatment. After multivariate adjustment the risk of cancer death was lower in patients 70 years or older (RR 0.53, 95% CI 0.30 to 0.90), while the risk of progression was lower in all age groups compared to that in men younger than 55 years (RR 0.57 to 0.62). On stratified subset analysis sPFS was progressively worse with younger age in patients with high risk pathological findings. However, the addition of age to multivariate models incorporating preoperative prostate specific antigen, pathological features and adjuvant therapy failed to improve their predictive value for CSS and sPFS. CONCLUSIONS: Despite more favorable clinicopathological features younger patients undergoing RRP for prostate cancer have survival similar to that of older counterparts. Given the greater proportionate impact of prostate cancer on survival, it is particularly important to pursue aggressive treatment in younger patients.

Age Factors↗
PubMed2006

Increasing prostate specific antigen following radical prostatectomy and adjuvant hormonal therapy: doubling time predicts survival.

PURPOSE: Adjuvant hormonal therapy may be beneficial in patients who are treated with RRP and found to have adverse pathological findings. We assessed the natural history of detectable PSA in such patients with particular emphasis on the prognostic usefulness of PSADT. MATERIALS AND METHODS: We identified 903 patients treated with RRP and adjuvant hormonal therapy (started less than 90 days postoperatively) for prostate cancer at our institution between 1990 and 1999. PSADT was calculated by log linear regression in men with 2 or more PSA measurements available at least 90 days apart. CSS and sRFS were estimated by the Kaplan-Meier method and analyzed using Cox proportional hazard models. RESULTS: At a median followup of 9.1 years PSA had become detectable in 369 of 771 patients (47.9%) who achieved an undetectable nadir. PSADT evaluable in 463 patients was less than 12 months in 68 (14.6%) and more than 10 years in 283 (61.1%). N stage and Gleason score were significantly associated with sRFS and CSS. PSADT was a significant predictor of sRFS and CSS in N+ and N0 cases with a cancer death HR of 0.55 (95% CI 0.43 to 0.71) and 0.50 (95% CI 0.31 to 0.79), respectively. The association between PSADT and survival persisted after multivariate adjustment for preoperative PSA, specimen Gleason score and seminal vesicle invasion. CONCLUSIONS: This study demonstrates that many patients have slow progression despite increasing PSA following RRP and adjuvant hormonal therapy. Nodal status, cancer grade and PSADT are predictive of sRFS and CSS, and may be a useful means of selecting patients for future adjuvant therapy trials.

Androgen Antagonists↗
PubMed2006

Malignant hypertension during cryoablation of an adrenal gland tumor.

The authors report a case of hypertensive crisis during cryoablation of an adrenal metastasis. This case is of particular interest not only because of the nature of the complication but also because of the timing of the hypertensive crisis. Based on their observations, the authors suggest that it may be prudent to pretreat this patient population with alpha-adrenergic blocking medications (eg, phenoxybenzamine), as is typically done for patients with neuroendocrine tumors such as pheochromocytoma. Preemptive intervention with these medications requires close collaboration between radiology and anesthesia care teams.

Adrenal Gland Neoplasms↗
PubMed2006

Does butyrate protect from colorectal cancer?

Butyrate, the four-carbon fatty acid, is formed in the human colon by bacterial fermentation of carbohydrates (including dietary fiber), and putatively suppresses colorectal cancer (CRC). Butyrate has diverse and apparently paradoxical effects on cellular proliferation, apoptosis and differentiation that may be either pro-neoplastic or anti-neoplastic, depending upon factors such as the level of exposure, availability of other metabolic substrate and the intracellular milieu. In humans, the relationship between luminal butyrate exposure and CRC has been examined only indirectly in case-control studies, by measuring fecal butyrate concentrations, although this may not accurately reflect effective butyrate exposure during carcinogenesis. Perhaps not surprisingly, results of these investigations have been mutually contradictory. The direct effect of butyrate on tumorigenesis has been assessed in a number of in vivo animal models, which have also yielded conflicting results. In part, this may be explained by methodological differences in the amount and route of butyrate administration, which are likely to significantly influence delivery of butyrate to the distal colon. Nonetheless, there appears to be some evidence that delivery of an adequate amount of butyrate to the appropriate site protects against early tumorigenic events. Future study of the relationship between butyrate and CRC in humans needs to focus on risk stratification and the development of feasible strategies for butyrate delivery.

Animals↗