Essay: Research Proposal: Why Pancreatic Cancer is often Diagnosed at A Later Stage Rather Than Earlier?

Abstract
Pancreatic cancer remains one of the cancers that are difficult to treat. Its survival rate is still very low. Diagnosis at its early stage rather than at advanced stage may increase the success rate of treating the disease. The proposed study will explore the literature to unravel the reason behind the late diagnostic of pancreatic cancer. The study will focus on examine how the early diagnosis of pancreatic cancer can increase the success rate of treating the disease, whether low understanding of clear signs and symptoms of pancreatic cancer leads to late stage diagnosis of the disease, and whether poor understanding of precipitating factors for pancreatic cancer are the main factor contributing to late diagnosis of the pancreatic cancer. Through the findings of this study, it will be possible to suggest the way forward in treating pancreatic cancer.
Introduction
Pancreatic cancer is a chronic disease with 5.8% five-year survival rate (Lemke et al., 2013). It is the fourth leading cause of cancer-related deaths in the United States (American Cancer Society, 2012; Sharma, Eltawil, & Renfrew, 2011). The overall age-adjusted mortality for pancreatic cancer is 10.8% for every 100,000 people per annum with 71 years median age at diagnosis (Dabizzi, Assef, & Raimondo, 2011). It is estimated that in 2012, there were about 44,000 new pancreatic cancer cases, a rare type of cancer entity when compared to other cancers of the gastrointestinal tract (Siegel et al., 2012). In 2013, approximately 45,000 people in the U.S. were diagnosed with pancreatic cancer (an increase of 1000 people). Of these, 38,000 died of the disease (Canto, Harinck, & Hruban, 2013). There are various types of pancreatic cancer. Adenocarcinoma, which accounts for about 90% of all pancreatic cancers cases, is the most common type of pancreatic malignancies in the United States (Sharma, Eltawil, & Renfrew, 2011). Canto, Harinck, and Hruban (2013) indicates that the lifetime risk of being diagnosed with pancreatic malignance is 1.47%. Interestingly, despite tremendous advances in cancer therapy and diagnostic, the survival rate remains relatively the same. This can partly be attributed to the fact that most patients with pancreatic cancer are diagnosed late or at advanced tumor stage and thus complete surgical resection of this tumor presents as the only cure. However, this surgical procedure can only be done in approximately 20% of patients diagnosed with this type of cancer (Hidalgo, 2010). Palliative treatment is provided to the remaining patients. More appalling is the fact that the survival rate in patients who receive palliative treatment is below six months (Lemke et al., 2013). Lemke et al. (2013) highlights three factors that lead to these alarming figures. Firstly, early specific symptoms of early pancreatic cancer are often unspecific or absent thus impeding early diagnosis of the disease. Secondly, the causes of pancreatic cancer remain largely unknown. Lemke et al. (2013) argues that this impedes the identification of the risk groups making it equally challenging to establish the preventive screenings for the disease, which for other malignancies such as colorectal breast cancer have been established (Lemke et al., 2013). Thirdly, pancreatic cancer has high metastasizing and invasive properties with a highly aggressive malignancy. On the contrary, Walter et al. (2011) argues that pancreatic cancer is highly resistant to most of conventional therapeutic regimes. Clearly, there are conflicting findings regarding the late and early diagnosis of pancreatic cancer and what informs them. However, it is undisputed that early diagnosis of pancreatic cancer can increase the success rate of treating the disease while late diagnosis of pancreatic disease reduces the success rate of treating the disease. This paper proposes a study to determine pancreatic cancer is often diagnosed late rather than early.
Research Question
‘ Why pancreatic cancer is often diagnosed at a later stage rather than at earlier stage’? Does early diagnosis of pancreatic cancer increase the success rate of treating the disease’? Does low understanding of clear signs and symptoms of pancreatic cancer lead to late stage diagnosis of the disease’? Does poor understanding of precipitating factors for pancreatic cancer the main factor contributing to late diagnosis of the pancreatic cancer?
Significance of the Study
Pancreatic cancer patients often face poor diagnosis. Majority (about 80%) are diagnosed when the disease is at its late and advanced stage. This contributes to low survival rate among these patients. Lemke et al. (2013) confirms that pancreatic cancer has a 5.8% five-year survival rate and that many patients diagnosed with it at advanced stage die within six months of diagnosis. Understanding the reasons why pancreatic cancer is often diagnosed at a later stage rather than at earlier stage is important for three main reasons. First, detecting the pancreatic cancer before it has widely spread can offer patients hope for a curative treatment and a chance for the long-term survival. Secondly, for patients with late or advanced disease, they may not be well enough to successful tolerate treatments that can help slow down the disease progression and prolong life. Thirdly, early diagnosis may allow the health practitioners more time to put in place measures that can help better manage side-effects and symptoms (Benson, Myerson, & Sasson, 2011).
Methodology
Data Collection and Data Analysis
To examine the relationship between early diagnosis of pancreatic cancer and the success rate of treating the disease, this study would employ a retrospective study design involving a cohort of 50 pancreatic cancer patients (including males and females) chart review from 2005-2015. A retrospective cohort study generally means looking back at the patient’s medical history. The researcher will compare medical records of patients who were diagnosed with pancreatic cancer during the early stages of the disease with those of patients who were diagnosed late with the disease and examine the differences in the success by which these patients were treated. As such, the patients will be divided into two: 25 patients diagnosed with early pancreatic cancer and 25 patients diagnosed with late pancreatic cancer. Seeking to determine the relationship between the understanding of clear signs and symptoms of pancreatic cancer and late stage diagnosis of the disease, the researcher will review these patients’ records while focusing on the stage of the disease at which the diagnosis was performed,
Literature Review
Nature of Pancreatic Cancer
Like other cancers that original from other organs, the classification of pancreatic tumors is based on the origin of the cell type, behavior and structure. The pancreas consists of various cell types (Benson, Myerson, & Sasson, 2011). The exocrine pancreas comprises of acinar cells and duct cells that release the gastric enzymes used in digestion and the endocrine pancreas that produce the ?? cells and other types of cells that produce hormones used for glucose metabolism and other functions (Ingkakul, Johnston, & Turner, 2011). Most of the exocrine pancreatic tumours are adenocarcinomas and originate in the lining of the pancreatic duct in the cells called epithelial cells. Adenocarcinomas account for approximately 90% of all the pancreatic cancers (Chiang et al., 2012). Mucinous tumour also a type of exocrine pancreatic cancer accounts for about 10% of pancreatic cancers. At diagnosis, these types of tumours are less invasive than other exocrine pancreatic cancers (Lemke et al., 2012). These tumours usually originate from the ductal epithelium of the pancreas, and form secretes mucin (the sac-like structures) within the pancreas (Jemal, Siegel, Xu, & Ward, 2010). The endocrine pancreatic cancers are less common. They account for less than 5% of the pancreatic tumours and occur at the rate of 5 per million person-years (Fang, Zhu, & Wang, 2012). These cancers originate from the pancreatic islets including ?? cells and ?? cells (Singh, Singh, & Chaudhary, 2010). These tumours do not ablate endocrine function rather they release high volumes of pancreatic hormones (Lemke et al., 2011). The two examples of endocrine pancreatic tumours: gastrinomas and insulinomas, are often detected from such symptoms as excessive hormone levels (Fang, Zhu, & Wang, 2012).
Risk Factors For Pancreatic Cancer
The exact risk factors for pancreatic cancer are poorly understood. However, there are studies that have identified certain factors reported to increase the likelihood of a person developing pancreatic cancer. According to American Cancer Society (2012) risk factors for pancreatic cancers include obesity, a family history of the disease (pancreatic cancer), personal or individual history of Hereditary Pancreatitis and chronic pancreatitis, tobacco use, age, race and diabetes. Smoking is reported to lead to about 20 to 30 % of the pancreatic cancer cases (Arora, 2010). Arora (2010) indicates that smokers are twice more likely to have pancreatic carcinoma than those who do not. The risk of developing pancreatic carcinoma increases with age. Leenders, Chuang, and Dahm (2012) indicated that most people diagnosed with the disease aged 60 and above. The incidence of developing pancreatic cancer is higher in African-Americans compared to persons of Hispanic, Asian or Caucasian descent. Also Ashkenazi Jews have higher incidence when it comes to developing pancreatic cancer possible because of mutation involving BRCA2 genes of breast cancer found in approximately 1% of people in this background. Obese individuals have about 20% higher chances of developing pancreatic cancer compared to individuals with normal weight. Leenders, Chuang, and Dahm (2012) indicate that the risk of developing the disease is higher in people who develop obesity during the childhood.
Individuals with pancreatitis have high likelihood of developing the disease. Pancreatitis is common among heavy alcohol consumers. Various autoimmune disorders and mumps virus can also lead to chronic pancreatitis. Chuan, Gallo, and Michaud (2011) shows that if an individual’s first relatives including the father, child, sibling, or mother had a pancreatic carcinoma then such a person has about 2 to 3 times risk of developing the disease. Parkin et al. (2011) indicates that the risk of developing pancreatic disease increases with a large number of first relatives is affected with the disease. The risk also increases if there a family history of colon or familial breast cancer, hereditary pancreatitis or familial melanoma. About 10% of cases of pancreatic cancer are reported to relate to the family history of pancreatic cancer (Cogliano, Baan, & Straif, 2011). Canto, Harinck, and Hruban (2013) found that about 10% of pancreatic cancer patients family history of pancreatic cancer. During 2004 and 2008, American Cancer Society (2012) reported the highest rates of pancreatic cancer among African-American men (21.3% per100, 000) and women (17.6% per100, 000). White men (16.9% per 100,000) had the second highest rates of pancreatic cancer (American Cancer Society (2012). American Cancer Society (2012) suggested that the burden of disease in these population and the differences in these three populations may be associated with the highest rates of diabetes mellitus and cigarette smoking among African-American men against white men and relatively higher body mass index (BMI) among African-American women compared to White women. The U.S. Preventive Services Task Force does not recommend screening for pancreatic adenocarcinoma (Canto, Harinck, and Hruban (2013). However, there are professional organizations that have recommended screening persons with increased risk of developing adenocarcinoma. Canto, Harinck, and Hruban (2013) suggested that those with more than two first-degree relatives with adenocarcinoma or pancreatic cancer should be screened for pancreatic cancer. Canto, Harinck, and Hruban (2013) also suggests that those with more than three blood relatives one of whom is the first-degree relative should be screened for pancreatic cancer. Canto, Harinck, and Hruban (2013) further indicates that some genetic factors such as Lynch syndrome, BRCA2, P16 mutations, PALB2, and Peutz-Jeutz-Jeghers Syndrome motivate testing for pancreatic cancer especially when the patient has a first-degree relative who had pancreatic cancer.
Staging and Diagnosis
Patients with pancreatic cancer often tend to remain asymptomatic or present with nonspecific symptoms including loss of appetite, fatigue and malaise until the disease has spread extensively and when jaundice, severe abdominal pains of weight loss appear. Late diagnosis makes it even difficult for surgical resection to be done. According to Lemke et al. (2013) about 85% of the pancreatic cancers are unresectable because of late diagnosis. Similarly, patients with unresectable tumors have a medium survival of between 6 and 10 months (Sharma, Eltawil and Renfrew, 2011). Symptoms that inform physicians to suspect pancreatic cancer include weight loss, epigastric pain, and jaundice (Canto, Harinck, and Hruban, 2013). Signs and symptoms alone are not sufficient to suspect and diagnose pancreatic cancer. Hidalgo (2010) sampled 70 patients suspected to have pancreatic cancer, and found out that 30 to had the disease, 16-irritable bowel syndrome, 9-other types of intra-abdominal cancers, 8-pancreatitis, and 7-other conditions. Hidalgo concluded that are other important clinical information including biopsies, laboratory values, and imaging tests should be explored to differentiate pancreatic cancer from these conditions. Dabizzi, Assef and Raimondo (2011) suggest that Multidetector computer tomography (MDCT) scan should be the first test to be performed to patients with symptoms suggesting pancreatic adenocarcinoma. Vincent, Herman, and Schulick (2011) holds that MDCT provides 3D (three dimensional) multiplanar reconstructions images makes it possible use a standardized pancreas protocol to determine the extent, spread and tumor size. However, this test is limited in its ability as it cannot detect small peritoneal/hepatic metastases and it does not as well differentiate benign and malignant pancreatic lesions (Vincent, Herman, & Schulick, 2011). Furthermore, MDCT can increase the patient’s risk to cancer since it does expose the patient to radiations (Tamm, Balachandran, & Bhosale, 2012).
Other imaging and procedures used to aid in aid in diagnosing pancreatic adenocarcinoma include positron emission topography-computed topography (PET-CT), encosccopic ultrasound with fine-needle aspiration (EUS-FNA) and magnetic imaging (MRI). The use of EUS-FNA involves orally introducing and advancing a specialized ultrasound probe via the upper gastrointestinal tract to the pancreas. The proximity of the ultrasound probe to the pancreas makes it possible for the probe to access and image the pancreas, the associated lymph nodes and related vasculature.
A small aspiration of suspicious lesions can be obtained to allow for cytologic evaluation. EUS-FNA can potentially differentiate benign from any malignant lesions. It can also characterize other types of lesions such as cystic pancreatic lesions (Tamm, Balachandran, & Bhosale, 2012). EUS-FNA has limitations including dependence on the endoscopist’s skills, invasiveness of the procedure, and the inability to assess distant metastases (Vincent, Herman, & Schulick, 2011). EUS-FNA is also relatively new. This may lead to a large variation in the technical skills of the endoscopist. EUS-FNA can potentially harm the patient by causing bleeding, adverse effects such as sedation, and perforation. PET involves scanning the whole body with a view to determining where there is the concentration of radioisotope tracer. It is used for distant metastases detection. The Fluorodeoxyglucose (FDG is the type of radioisotope tracer that is commonly used (Lemke et al., 2013). This radioisotope tracer can potentially locate metabolically active sites such as sites with inflammation and malignant tumors and can be useful in distinguishing pancreatic tumors and other metabolically active masses from malignant tumors. Combined CT and FGD-PET can add precise CT anatomic localization to functional PET data. These two methods are concurrently acquired and date from the two merged. Magnetic Resonance Imaging is the alternative to MDCT. It is the initial imaging test used in patients suspected to have pancreatic cancer.
Most pancreatic adenocarcinoma cases are often diagnosed at a late/advanced stage. This precludes surgical resection (American Cancer Society, 2012). American Cancer Society (2012) asserts that when pancreatic cancer is diagnosed at late stage, there is about 2% 5-year survival. The 2010 AJCC (American Joint Committee on Cancer) System is the system that is commonly used for staging pancreatic cancer (Tamm et al., 2013).
Limitation of the Study
Although a lot remains to be done, this study will generate important findings regarding the best way forward to managing pancreatic cancer. In other words, given the limitation of the data collection and processing method, the researcher can nevertheless confirm that this study has some limitations. Although the proposed study may yield some preliminary findings, there are flaws in its design. Several caveats must be noted with regard to the proposed study.
The major limitation of the proposed study concerns factors that lead to late diagnosis rather than early diagnosis of pancreas cancer. There may be relevant factors that influence the late diagnosis of the disease. However, it will be beyond the scope of the proposed study to extend the discussion to the ongoing debates. Factors leading to late diagnosis of pancreatic cancer are still at large tentative.
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