Intraductal papillary mucinous neoplasms of the pancreas: clinical surveillance and malignant progression, multifocality and implications of a field-defect

Intraductal papillary mucinous neoplasms (IPMNs) are a heterogeneous group of mucin producing cystic tumors that involve the main pancreatic duct and/or branch ducts and may be associated with invasive carcinoma. Predicting the risk of malignant transformation of an IPMN lesion can be challenging. The Sendai criteria, based in large part on radiographic imaging features, help guide surgical intervention based on the stratification of cysts into high and low risk lesions for malignancy. Invasive carcinoma may develop in the index IPMN lesion or in a separate site within the pancreas, supporting the concept of a field defect in IPMN tumorigenesis. This stresses the importance of evaluation of the entire pancreas upon diagnosis of IPMN and continued surveillance of the residual pancreas following resection. Herein, the authors summarize the data presented at the 2012 ASCO Gastrointestinal Cancers Symposium regarding prevalence and site of invasive carcinoma detected in patients undergoing surveillance for IPMN (Abstract #152).

[Pancreatic ductal carcinoma concomitant with intraductal papillaly mucinous neoplasm]

IPMN is a slow-growing tumor and has a good prognosis, but is very often associated with a high incidence of pancreatic ductalcarcinoma(DC). Unlike IPMN, DC progresses rapidly, and has a poor prognosis. However, DC concomitant with IPMN has a better prognosis than DC without IPMN. The reason for the good prognosis of the former is undetermined, but perhaps it is the early detection of DC or its not so malignant behavior. It is important to thoroughly examine the entire pancreas for the potentialco -occurrence of DC in patients with IPMN.

Epithelial ovarian cancer and exposure to dietary nitrate and nitrite in the NIH-AARP Diet and Health Study

Ovarian cancer is a leading cause of cancer death among women in the United States and it has the highest mortality rate of all gynecologic cancers. Internationally, there is a five-fold variation in incidence and mortality of ovarian cancer, which suggests a role for environmental factors, including diet. Nitrate and nitrite are found in various food items and they are precursors of N-nitroso compounds, which are known carcinogens in animal models. We evaluated dietary nitrate and nitrite intake and epithelial ovarian cancer in the National Institutes of Health (NIH)-AARP Diet and Health Study, including 151 316 women aged 50-71 years at the time of the baseline questionnaire in 1995-1996. The nitrate and nitrite intake was assessed using a 124-item validated food frequency questionnaire. Through 31 December 2006, 709 incident epithelial ovarian cancer cases with complete dietary information were identified. Using Cox proportional hazards regression to estimate hazard ratios and 95% confidence intervals (CIs), women in the highest intake quintile of dietary nitrate had a 31% increased risk (95% CI: 1.01-1.68) of epithelial ovarian cancer, compared with those in the lowest intake quintile. Although there was no association for total dietary nitrite, those in the highest intake category of animal sources of nitrite had a 34% increased risk (95% CI: 1.05-1.69) of ovarian cancer. There were no clear differences in risk by histologic subtype of ovarian cancer. Our findings suggest that a role of dietary nitrate and nitrite in ovarian cancer risk should be followed in other large cohort studies.

Clinical course of colorectal cancer in patients with ulcerative colitis

BACKGROUND

Colorectal cancer that develops as a complication of ulcerative colitis (UC) is a serious problem that affects the patient's prognosis. Such cancer is characterized by development at an early age, a high incidence of multiple tumors, poorly differentiated carcinoma and mucinous carcinoma. Special attention should therefore be paid to the diagnosis and treatment of such cancer.

PATIENTS AND METHODS

One hundred and seventy-four patients with UC underwent surgery in our Department between July of 1985 and December of 2009. Of these, 22 had concomitant colorectal cancer. We performed a retrospective study to investigate these patients.

RESULT

The incidence of colorectal cancer as a complication of UC was 12.6%. The male:female ratio was 14:8, and the average age at surgery was 54.6 (32-79) years. In addition, when examining the lesion type of UC, it was revealed that the total colitis type accounted for 77.3% of colorectal cancer cases in UC patients. Regarding the site of development of colorectal cancer, 14 out of the 22 patients had cancer in the distal end. The average period from the development of UC to the diagnosis of colorectal cancer was 14.7 (0.6-40.5) years. The cumulative incidence rates over 10 and 20 years were 5.1% and 17.5%, respectively. Histologically, poorly differentiated adenocarcinoma and mucinous carcinoma were confirmed in 38.1% of the patients, and dysplasia was also confirmed in 53.8%. In addition, multiple tumors were confirmed at a rate as high as 27.3%. Cancer detection through surveillance has increased, and colorectal cancer was detected in 13 out of the 22 patients by routine surveillance. In cases where cancer was detected by surveillance colonoscopy, 46.2% of lesions were early cancer. We therefore consider that surveillance is useful. However, we experienced a case that could not be diagnosed by endoscopy that was successfully diagnosed by fluoroscopy. The case was noted to have stricture.

CONCLUSION

The cumulative incidence rates over 10 and 20 years were 5.1% and 17.5%, respectively. Since the average period from the onset of UC to the diagnosis of colorectal cancer was 14.7 years, routine surveillance examinations are necessary for patients with a history of UC of at least 10 years. In addition, patients with strictures must be examined using both colonoscopy and fluoroscopy because diagnosis with colonoscopy alone may be inadequate.

Mucinous carcinomas of the ovary and colorectum: different organ, same dilemma

Mucinous carcinomas are uncommon histological types that affect several organ sites. Primary mucinous carcinomas of the ovary are distinct from other ovarian carcinoma types, but they can pose a particular challenge for correct diagnosis from metastases, which most usually originate from the colorectum. Correct diagnosis is the mainstay of treatment, because standard practice states that protocols are tailored to the primary organ site. Little is known of mutational alterations in primary and metastatic mucinous carcinomas of the ovary, and few markers exist that can discriminate between them. We reviewed commonalities between ovarian and colorectal mucinous carcinomas with respect to aetiology, molecular alterations, differential diagnosis, and implications for treatment. Although primary mucinous carcinomas of the ovary and colorectum share similar mutational patterns and unfavourable outcomes at advanced stage, compared with their non-mucinous counterparts, important differences exist with respect to mucin localisation and specific molecular alterations. Technologies--eg, next-generation sequencing--could aid identification of additional driver molecular changes that will help clarify the relation between mucinous carcinomas from different organ sites. Perhaps, then, we can consider moving towards testing and adoption of therapeutic approaches tailored to molecular characteristics of mucinous carcinomas, irrespective of organ site, so patients' survival can be optimised.

[Relationship between histologic type and location of gastric adenocarcinoma in the Rebagliati Hospital]

INTRODUCTION

There is epidemiologic evidence that suggest the relation between the histological type and location of gastric adenocarcinoma. Knowing that there is a predominance of Helicobacter pylori infection in the antral region and this is considered an environmental factor; make us suppose that there is a relation among intestinal type and distal location.

OBJECTIVE

The aim of this study is to investigate the relation among histological type and location of gastric cancer, using the Lauren classification and the Japanese Gastric Cancer Association classification.

METHOD

During the period between January 1st 2007 and December 31th 2010, 460 patients with the proven diagnostic of adenocarcinoma were admitted for surgical treatment at the gastric cancer specialized ward of Rebagliati National Hospital, Lima, Peru.

RESULTS

Female was more frequent in diffuse type (39% vs. 33%; p: 0,153), the mean age among intestinal type is greater than diffuse type (70,7 vs. 62,6 años; p<0,001). There is association among poorly differentiated with upper location (22% vs. 12,7%; p = 0,009), signet cell with middle location (50% vs. 32,5%; p: 0,006), tubular type with distal location (57,6% vs. 42,8%; p: 0,002), intestinal type with distal location (58,3% vs. 44,1%; p: 0,004), and diffuse type with upper location (19,3% vs. 12,5%; p: 0,049).

CONCLUSION

Adenocarcinomas histologically differentiated or intestinal type are associated with distal location. Poorly differentiated type and signet ring cell type are associated with upper and middle location respectively.

Clinicopathological characteristics of mucinous and non-mucinous adenocarcinoma in the colon and rectum in Rajavithi Hospital, Thailand

BACKGROUND

The clinicopathological characteristics of colorectal mucinous adenocarcinoma (MA) are still controversial. Most of the reports suggested that MA were associated with worse clinicopathological behavior and poorer prognosis than non-mucinous adenocarcinoma (NMA) while the others showed no difference.

OBJECTIVE

To compare clinicopathological characteristics and tumor recurrence of MA patients with those in NMA patients.

MATERIAL AND METHOD

During the period of 2000 to 2009 in Rajavithi Hospital, a total of 427 colorectal adenocarcinoma patient records consisting of 407 NMA and 20 MA were included in this study. Mean age, tumor location, TNM staging at diagnosis, T-stage, N-stage, preoperative CEA level and recurrent rate of MA patients were compared with those of NMA patients.

RESULTS

The distribution of MA patients for gender, mean age, tumor location, TNM stage and preoperative CEA level were similar to those of NMA patients (all p > 0.05). Only the tumor recurrence in MA was significantly more common than that in NMA (p = 0.020, OR = 3.28 (1.14-9.43)), whereas the TNM stage was not significantly different from NMA (p = 0.530). The metastatic site and pattern of metastasis also showed no statistical significance (p = 0.125).

CONCLUSION

The prognosis of MA is poorer than NMA. This may be associated with mucinous histological type itself.

Intraductal papillary mucinous neoplasm (IPMN) and chronic pancreatitis: overlapping pathological entities? Two case reports

CONTEXT

Intraductal papillary mucinous neoplasms (IPMNs) are a recently classified pancreatic neoplasm with an increasing incidence. IPMN is often misdiagnosed as chronic pancreatitis because of symptoms of relapsing abdominal pain, pancreatitis, and steatorrhea and imaging findings of a dilated pancreatic duct of cystic lesions that are frequently confused with pseudocysts. Early recognition of IPMN allows for prompt surgical resection before malignant transformation.

CASE REPORTS

We report two cases of patients with long histories of chronic pancreatitis (more than 15 years) that went on to develop IPMN. Both patients presented with symptoms of abdominal pain, nausea, steatorrhoea and eventually weight loss. Biochemical and radiological findings were suggestive of chronic pancreatitis although no clear causes for this were identified. Both patients were followed up with multiple repeat scans with no reported sinister findings. Many years after the initial diagnosis of chronic pancreatitis, radiological investigations identified pathological changes suggestive of neoplastic development and histology confirmed IPMN.

CONCLUSIONS

The cases demonstrate the ongoing challenges in diagnosing and managing IPMN effectively; highlights the important aspects of epidemiology in differentiating chronic pancreatitis and IPMN; continues the discussion surrounding the relationship between IPMN and chronic pancreatitis.

Influence of age on PPV of sonographic BI-RADS categories 3, 4, and 5

PURPOSE

The purpose of this retrospective study was to calculate the positive predictive value (PPV) of sonographic Breast Imaging Reporting and Data System (BI-RADS) categories 3, 4, and 5 in different age groups to investigate whether age influences the PPV of the BI-RADS category in breast ultrasound.

MATERIALS AND METHODS

From our sonography-guided core biopsy database of breasts between 2006 and 2008, we identified 2817 BI-RADS category 3, 4, and 5 lesions with known pathological diagnosis in 2587 women, all of whom underwent the earlier breast assessment via ultrasound with a sonographic BI-RADS lexicon and later sonography-guided core biopsy. All lesions were classified into three age groups (< 45, 45 - 59, and > 59 years). The age-related PPVs of each BI-RADS category among three age groups were calculated on the basis of pathological diagnoses and were compared using a χ(2)-test.

RESULTS

The overall PPV of each BI-RADS category was 2.2 % in category 3, 6.5 % in category 4a, 35.2 % in category 4b, 79.6 % in category 4c, and 99.6 % in category 5. The age-related PPVs of category 3 varied significantly among the three age groups (0.9 % versus 3.9 % versus 2.0 % p = 0.048), and notably, the age-related PPV in group 2 was higher than the others. Additionally, there was a significant positive association between the age-related PPVs and increasing age in categories 4a and 4b (4a, p < 0.0001 and 4b, p = 0.0139), but not in categories 4c and 5 (4c, p = 0.1853 and 5, p = 0.2871).

CONCLUSION

The incidence of female breast cancer differs not only in different sonographic BI-RADS categories, but also in different age groups. Therefore, more attention should be paid to the special age group that we found for sonographic BI-RADS categories 3, 4a, and 4b.

Mucinous adenocarcinoma of the colon - a histochemical study

Colorectal carcinoma is a major cause of cancer associated with a high rate of morbidity and mortality in the western world. One of the pathologic features considered to be important for prognostic is mucin production. Many authors confirmed that colon carcinomas with high mucin content tend to re-occur locally and carry a poor prognosis. For histochemical evaluation of mucin content, we investigated 149 patients who underwent surgical resection of sporadic colon adenocarcinomas, all over a 5-year period. For histological classification we used the WHO recommendation (2000) and to be more accurate we sub-classified mucinous adenocarcinomas by morphometrical analysis in three categories: pure mucinous, with extracellular mucin more than 80% of the tumoral volume; mixed type, with 50-80% extracellular mucin; and mixed type with less than 50% extracellular mucin. For histochemical investigation, we used stains such as: mucicarmine, PAS ÷ Alcian Blue and High Iron Diamine ÷ Alcian Blue. Our study proved the predominance of mixed mucinous adenocarcinomas with less than 50% extracellular mucin, followed by the pure mucinous type. From the biochemical composition's point of view, the predominant cases were those with acidic mucins, especially in pure mucinous adenocarcinomas (>90%), while those with mixtures of acidic and neutral mucins were present in 62% of the cases. In addition, our study showed the prevalence of sialomucins over sulphomucins (68%), particularly in pure mucinous adenocarcinomas (77%). Clinical pure mucinous forms were detected mainly in advanced stages, but in terms of lymph node metastasis rate, they were secondary after mixed type with 50-80% extracellular mucin.

Distribution of a single nucleotide polymorphism of insulin-like growth factor-1 in colorectal cancer patients and its association with mucinous adenocarcinoma

PURPOSE

To analyze the difference in the distribution of an insulin growth factor-1 (IGF-1) polymorphism (-2995 C/A) between young and old colorectal cancer (CRC) patients.

METHODS

Information from 950 CRC patients undergoing surgery at the Taipei Veterans General Hospital between 2000 and 2005 was collected. The IGF-1 polymorphism was analyzed in patients in extreme age ranges at the time of CRC onset (i.e., under the 20th and above the 80th percentiles, respectively). Associations between clinicopathological variables and the IGF-1 polymorphism were analyzed.

RESULTS

Young CRC patients had a higher frequency of advanced disease (58.7%) and mucinous adenocarcinoma (20%) than old CRC patients. Among old CRC patients, the frequency of the AA genotype of IGF-1 was 12.7% (24/189), which was significantly higher than in young patients (4.2%). Other clinicopathological factors including tumor location, differentiation, lymphovascular invasion, and TNM stage were not associated with the AA genotype of IGF-1. Mucinous differentiation (but not the other clinicopathological factors) was significantly associated with the CA/AA genotype of IGF-1 (39/195).

CONCLUSIONS

Older patients had a higher frequency of the AA genotype of IGF-1(-2995 C/A), while younger patients more often had advanced disease and mucinous adenocarcinoma.

CYP17 (T-34C) and CYP19 (Trp39Arg) polymorphisms and their cooperative effects on breast cancer susceptibility

BACKGROUND

Breast cancer is the commonest cancer among women in industrialized countries. Most sporadic breast carcinomas are likely to be caused by low-penetrance genes. Genes encoding enzymes involved in estrogen and carcinogen metabolism are among these low-penetrance genes. In this study, for the first time the T/C (A1/A2) polymorphism at the 5' untranslated region (UTR) of CYP17 and the Arg/Trp (T/C) polymorphism at codon 39 of CYP19 among genes regulating endogenous estrogen levels was studied.

PATIENTS AND METHODS

Fifty-five female breast cancer patients and ninety-one controls took part in the study. DNA was extracted from paraffin-embedded tissues for the patients and from blood cells for the controls. The distribution of genotypes was determined using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) techniques.

RESULTS

The frequency of the TC genotype of CYP19 was significantly higher in the patient group (p<0.001, kappa(2): 12.31, OR: 7.30, 95% CI: 2.29-25.64). CYP17 frequencies were similar to those in Caucasian populations. In combined analysis, when the high risk alleles were evaluated together, the results reached significance (p=0.006, kappa(2)=7.01, OR: 2.53, %95 CI: 1.26-5.07) for the A2 allele of CYP17 and the C allele of CYP19, being more frequent in the patient group compared to the control. The risk possesed by the TC varient of CYP19 was reduced when evaluated with A1, the protective allele of CYP17 (p=0.082). The cumulative protective effects of both A1 allele and the TT genotype were ascertained to occur significantly less frequently in the patient group (p=0.001, kappa(2): 10.53, OR: 8.47, %95 CI: 1.9-37.04).

CONCLUSION

The results were consistent with the individual studies of CYP17 and CYP19 in the literature, however, in combined analysis of the alleles of the two genes, the frequency of high risk alleles was higher and the frequencies of low risk alleles were lower in the patient group. The CYP17 A1 + CYP19 TT haplotype may be protective for breast cancer.

Risk factors for epithelial ovarian cancer by histologic subtype

Previous epidemiologic studies suggest that the major histologic subtypes of epithelial ovarian cancer may have different risk factor profiles; however, no known prospective study has systematically examined differences in risk by subtype. The authors used Cox proportional hazards regression, stratified by histologic subtype and time period, to examine the association between ovarian cancer risk factors and incidence of serous invasive, endometrioid, and mucinous ovarian cancers in the US Nurses' Health Study (1976-2006) and Nurses' Health Study II (1989-2005). For each exposure, they calculated P-heterogeneity using a likelihood ratio test comparing models with separate estimates for the 3 subtypes versus a single estimate across subtypes. Analysis included 221,866 women and 721 cases with the histologies of interest (496 serous invasive, 139 endometrioid, 86 mucinous). In analyses of reproductive/hormonal exposures, the associations with age, duration of breastfeeding, age at natural menopause, and duration of estrogen use differed significantly by subtype (all P-heterogeneity < or =0.05). The associations with several nonreproductive exposures also appeared to vary by subtype, but only the association with smoking differed significantly (P-heterogeneity = 0.03). Results suggest that associations with several ovarian cancer risk factors vary by subtype, and these differences are consistent with known similarities between each major histologic subtype and its normal tissue counterpart.

Intraductal papillary mucinous tumors of the pancreas

Intraductal papillary mucinous tumors (IPMTs) are benign and malignant lesions that arise from the epithelial lining of main pancreatic duct and/or branch pancreatic ducts, with excessive mucin production (especially hyperplastic/adenomatous variety). Based on the degree of cytoarchitectural atypia on microscopic examination, IPMTs are classified as benign, borderline, carcinoma in situ and invasive tumors. Imaging examinations are very important to establish the diagnosis. Two or more tests are usually required. Transabdominal ultrasound, endoscopic ultrasound, computed tomography, magnetic resonance cholangiopancreatography and endoscopic retrograde cholangio-pancreatography have been used for the diagnosis of IPMTs. The correct diagnosis, achieved until recently only with endoscopic retrograde cholangiopancreatography, can be currently obtained with non-invasive imaging modalities, particularly computed tomography and magnetic resonance imaging. Confirmation of the diagnosis requires, however, endoscopic-ultrasound fine-needle aspiration biopsy, followed by cytological or microhistological exams. The natural evolution of IPMTs is still not clear and the management is consequently still evolving.

[Epidemiological study, pathologic evaluation and prognostic factors of colorectal mucinous vs non-mucinous adenocarcinoma (a series of 196 patients)]

BACKGROUND

Colorectal carcinoma is one of the main causes of cancer death in the worldwide with a decrease survival rate in relationship with a later diagnosis of advanced disease.

AIMS

This study highlights the particular epidemiological, clinicopathological and immunohistochemical colorectal cancer profile. Indeed, our results differ markedly from that reported in the literature.

METHODS

We underwent a retro and prospective study interesting 196 patients with colorectal carcinoma diagnosed in the pathological and cytological laboratory of Mongi Slim Hospital (Tunisia). Age at diagnosis, mode of presentation, sex, tumour location, macroscopic and histological features, TNM and Astler Coller stage were assessed and evaluated.

RESULTS

We report here a particular epidemiological pattern which is characterised by younger age of the patients, equally distribution between men and women, predominant sporadic carcinomas and preponderance of rectosigmoid location. The poorer degree of differentiation and mucinous subtype are correlated with an advanced stage. It is also correlated with more frequent vascular embols, neural invasion and metastatic nodes. Furthermore, immunohistochemical analysis of galectin-3 showed a significant difference between mucinous and non mucinous adenocarcinoma.

CONCLUSION

Based on the presented data, the epidemiological pattern and the anatomic distribution especially in the rectosigmoid region suggest diet and lifestyle to be primordial risk factors of colorectal tumorigenesis.

Pancreatic neuroendocrine tumors among patients with intraductal papillary mucinous neoplasms: real association or just a coincidence?

CONTEXT

Intraductal papillary mucinous neoplasms (IPMNs) are being recognized with increased frequency and are the most common indication of pancreatic surgery at specialized centers. Many IPMN patients are found to have non-IPMN related pancreatic tumors like pancreatic neuroendocrine tumors (PNTs).

OBJECTIVE

To study the prevalence of PNTs among patients with IPMN.

METHODS

Patients who underwent surgical resection for IPMN were retrospectively reviewed for presence of histologically proven PNTs. The PNTs were evaluated for the patient demographics, imaging characteristics, histology, and surgical staging.

RESULTS

Between January 2002 and October 2007, 104 patients underwent surgery for pancreatic IPMN. Among these, 4 patients (3.8%) were diagnosed with concomitant PNTs (1 male, 3 females; median age 72 years). Three patients had branch duct type-IPMN (cyst size: 19 mm, 15 mm and 27 mm), and one had main duct type-IPMN. Only one branch duct IPMN had adenocarcinoma, other three had low grade/borderline dysplasia. The median size of PNT was 10 mm (range 8-16 mm) and all were missed on the cross sectional imaging. Three patients were recognized by endoscopic ultrasound (EUS) and the fine needle aspiration confirmed the diagnosis in 1/3. Only one patient had metastatic PNT to lymph node, the other three were low grade lesions.

CONCLUSION

IPMN and PNT can coexist. The prevalence of PNT among IPMN patients is low (3.8%). Our study is limited by small sample size. Large studies with large number of patients are needed to further explore this association.

Breast cancer and cyclin D1 gene polymorphism in Turkish women

BACKGROUND

Cyclin D1 protein plays an important part in regulating the progress of the cell during the G(1) phase of the cell cycle. It has been suggested that G870A polymorphism at the exon4/intron4 splicing region of the CCND1 gene may play a role in tumorigenesis and invasiveness.

PATIENTS AND METHODS

A case-control study was performed to test the association between G870A polymorphisms in the CCND1 gene and breast cancer risk and cancer progression. For this purpose, 38 patients with breast cancer and 64 healthy women controls were included in the study. The CCND1 G870A polymorphisms in our study groups were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) using peripheral blood samples.

RESULTS

A significant difference was found in the distribution of the GG, AG and AA genotypes between the patient group and the control group (p=0.021). A lower risk (odds ratio 0.435, 95% confidence interval 0.223-0.846) was found to be associated with heterozygote AG individuals when compared with homozygote allele carriers in breast cancer. The cyclin D1 A870G genotype was associated with capsular invasion (p=0.02).

CONCLUSION

The risk of breast cancer development and prognosis may be associated with genetic variation in the CCND1 genotype, which may be used as a biomarker for further studies.

Young-age onset of colorectal cancer in Israel

AIM

The study was conducted to investigate the differences in clinical-pathological, ethnic, and demographic presentations and the expression of mismatch repair proteins in a cohort of young-onset (</=50 years) versus late-onset Israeli patients (>50 years) with colorectal cancer.

MATERIALS AND METHODS

Clinical, demographic, and histopathological data of patients with colorectal cancer were collected retrospectively from medical records and pathology reports.

RESULTS

Ninety patients, 50 years of age or younger with a mean age of 42 years were compared with a group of 190 patients above 50 years of 50 (see Table 1). Sixty percent of the young-onset patients were females, compared to 40% in the older age group (P = 0.02). Twenty-one percent of the young-onset patients were Arabs as compared to 2% of older-onset patients (P = 0.001). Younger patients displayed a higher percentage of mucinous cancers and a higher percentage of diagnosis at an advanced stage of disease; 40% of young-onset versus 31% of older-onset patients presented Duke's stages C and D (P = 0.02).

CONCLUSIONS

Younger age of onset colorectal cancer in our cohort of Israeli patients is associated with higher percentage of Arab patients, mucinous cancers, female gender, and advanced stage at diagnosis.

[Colon cancer in Iceland 1955-2004. Study on epidemiology, histopathology and gender difference]

OBJECTIVE

Colon cancer is the third most common cancer in Iceland. The aim of this study was to analyze the epidemiology and histopathology of colon cancer in Iceland, resection rate and the difference between men and women.

MATERIAL AND METHODS

Pathology and autopsy reports for all patients diagnosed with colon cancer between 1955 and 2004 where reviewed. All the histopathology material was re-evaluated. Demographical information and pathological findings were registered. Age-standardized incidence was calculated for both men and women. Gender difference was evaluated. Time trend was evaluated by linear regression.

RESULTS

After re-evaluation 2293 cases remained (1148 males and 1145 females). The incidence increased for men from 7.5, to 22.2/105 and for women from 8.6 to 15.1/105. Most tumors were located in the sigmoid colon (35%). Surgical rate increased from 50% to 85%. Adenocarcinomas where 84% and mucinous adenocarcinoma 7%. Altogether 7% of cases were TNM-stage I, 32% were stage II, 24% stage III, 21% in stage IV and stage was unknown in 16% of cases. Slight gender difference was observed regarding grade, vessel invasion, depth of invasion and anatomic subsite.

CONCLUSION

Incidence of colon cancer increased considerably, mainly for men. Surgical rate and pathology of colon cancer is similar to that reported elsewhere except that there are somewhat fewer cases in TNM-stage I. Little gender difference was observed in the pathological parameters analysed.

[Frequency and clinicopathological associations of K-ras mutations in Venezuelan patients with colo-rectal cancer]

Mutations in the K-ras oncogene are common in colo-rectal cancer, which affect the biological behaviour and may influence the susceptibility to therapy in these tumors. The objective of this work was to identify the types of K-ras mutations observed in referred patients with colo-rectal cancer and to relate them to their degree of histological differentiation and clinical stage. Histopathological and clinical data were obtained from medical records. DNA was obtained from both, fresh tissue and tumor tissue embedded in paraffin. The K-ras gene was amplified through the polymerase chain reaction (PCR) and the amplified fragments were digested with restriction enzymes. We found mutations in codons 12 and 13 of the K-ras oncogene in 23.33% of patients. Of these, 28.57% were located at codon 12, 57.14% were at codon 13 and 14.29% at both codons. They were more frequent in tumors located in the left hemicolon and, according to their histological type, were more frequent in well differentiated adenocarcinomas (58.70%) and in mucinous (28.57%). The identified mutations were more frequent in advanced stages (C2) of Dukes' classification. The molecular analysis of the K-ras oncogene made mutations evident, which could be useful in the diagnosis and prognosis of colorectal tumors. The frequency of mutations found in this work is similar to some of those reported worldwide; however, they differ in the more frequent type of mutation, which, in our study, was located at codon 13 in more than 50% of the cases.

Body mass index and risk of ovarian cancer

BACKGROUND

Convincing epidemiologic evidence links excess body mass to increased risks of endometrial and postmenopausal breast cancers, but the relation between body mass index (BMI) and ovarian cancer risk remains inconclusive. Potential similarities regarding a hormonal mechanism in the etiology of female cancers highlight the importance of investigating associations according to menopausal hormone therapy (MHT) use. However, to the authors' knowledge, data addressing whether the relation between BMI and ovarian cancer differs by MHT use are very sparse.

METHODS

The authors prospectively investigated the association between BMI and ovarian cancer among 94,525 US women who were followed between 1996 through 1997 to December 31, 2003. During 7 years of follow-up, 303 epithelial ovarian cancer cases were documented.

RESULTS

Compared with normal weight women (BMI of 18.5-24.9 kg/m(2)), the multivariate relative risk (MVRR) of ovarian cancer for obese women (BMI of >or=30 kg/m(2)) in the cohort as a whole was 1.26 (95% confidence interval [95% CI], 0.94-1.68). Among women who never used MHT, the MVRR for obese versus normal weight women was 1.83 (95% CI, 1.18-2.84). In contrast, no relation between BMI and ovarian cancer was apparent among women who ever used MHT (MVRR = 0.96; 95% CI, 0.65-1.43; P interaction = 0.02). Exploratory analyses also suggested a positive association between BMI and ovarian cancer among women without a family history of ovarian cancer (MVRR comparing obese vs normal weight women = 1.36; 95% CI, 1.00-1.86), but no relation with BMI was apparent among women with a positive family history of ovarian cancer (MVRR = 0.74; 95% CI, 0.34-1.62 [P interaction = .02]).

CONCLUSIONS

Based on the results of the current study, the authors suspect that obesity is associated with enhanced ovarian cancer risk through a hormonal mechanism.

A retrospective review with long term follow up of 11,400 cases of pure mucinous breast carcinoma

BACKGROUND

Pure mucinous breast carcinoma (PMBC) is a rare histologic type of mammary neoplasm. It has been associated with a better short-term prognosis than infiltrating ductal carcinoma (IDC) but identical long-term survival curves have been reported. The value of tumor size for TNM staging has been challenged because of the mucin content of the lesions. This study presents a large PMBC series with 20 years follow up as compared to IDC. The relative significance of a variety of common prognostic factors is calculated for this uncommon histology.

MATERIALS AND METHODS

A retrospective analysis of all PMBC cases reported in the SEER database between 1973 and 2002 was conducted. Overall survival (OS) and disease specific survival (DSS) were calculated at 5, 10, 15 and 20 years of follow up. Those curves were compared with all the IDC cases reported into the database during the same period. The prognostic significance of gender, race, laterality, age at diagnosis, T and N status, estrogen and progesterone receptors and administration of radiation therapy was calculated by univariate and multivariate analysis.

RESULTS

There were 11,422 PMBC patients reported. The median age at diagnosis was 71 years (Range 25-85). Fifty three percent of the tumors were well differentiated, 38% were moderately differentiated and the remaining 9% were poorly differentiated or anaplastic. The majority of the tumors were located in the upper outer quadrant (44%) the other 56% were roughly evenly divided between the upper inner, lower inner, lower outer and central quadrants. Eighty six percent of the patients had only localized disease at the time of surgery without nodal or distant disease while 12% had regional nodal involvement and 2% had distant metastases. The PMBC cases showed a better differentiation with lesions of lesser grade and more frequent ER/PR expression, smaller size and lesser nodal involvement when compared to the IDC cases of the same period. Kaplan Meier survival curves revealed a 5 years. breast cancer specific survival rate of 94%. Although slowly decreasing with time, 10, 15 and 20 years survival were 89%, 85% and 81% respectively compared to 82% (5 year), 72% (10 year), 66% (15 year) and 62% (20 year) for IDC. There were no significant differences in overall survival. Multivariate analysis by Cox regression revealed the nodal status (N) to be the most significant prognostic factor followed by age, tumor size (T), progesterone receptors and nuclear grade. Disease specific survival curves stratified for nodal status revealed a highly significant difference between node negative and node positive patients. The addition of radiation therapy after surgery did not significantly improve overall survival.

CONCLUSIONS

This large retrospective comparative analysis confirms the less aggressive behavior of PMBC compared to IDC. This favorable outcome is maintained after 20 years. This tumor presents typically in older patients and is rarely associated with nodal disease. Positive nodal status appears to be the most significant predictor of worse prognosis.