Exploring Strategies for Earlier Colon Cancer Detection in Sub-Saharan Africa

Sub-Saharan Africa: Sub-Saharan AfricaYoanna S. Pumpalova, MD, took a geographically challenging route before arriving at her position as Assistant Professor of Medicine in the Department of Hematology and Oncology at Columbia University Irving Medical Center. In addition to her teaching responsibilities, she specializes in gastrointestinal oncology and is committed to furthering the field of global oncology by partnering with academic institutions in sub-Saharan Africa to conduct research aimed at improving local cancer outcomes. Pumpalova was born in Bulgaria and at the age of 7 moved to Malta with her parents to escape the constraints of communism and economic turmoil in the mid 1990s. “My father was a professional soccer player in Bulgaria and had an opportunity to transition to coaching in Malta. I learned to speak English there,” she recalled. “When I was 13, our family moved to Princeton, NJ, where my father developed a youth soccer program. Coming to the United States from Malta was an easier transition than from Bulgaria to Malta, because we already had learned the language. That was a big advantage. With Princeton University being right there, there was a large international community in the town, so Princeton was a very nice place to live and go to high school.”Yoanna S. Pumpalova, MD: Yoanna S. Pumpalova, MDFinding her way to medicine was an outgrowth of her secondary school education. “I had an awesome biology teacher at Princeton High School—Dr. Baum was super dynamic and very inspirational. Later I went to Barnard College, which has a very strong pre-med program that I was part of. I really liked science and I loved talking to people, so medicine was a reasonable choice,” she said. That choice took her to Weill Cornell Medical School, which is where she had the opportunity to develop and pursue her global health interest. “Cornell had a well-developed, student-led global health curriculum,” Pumpalova noted. “It consisted of extra lectures, small groups, and journal clubs that I could do adjacent to the regular curriculum. I also had the opportunity to go to Ghana for a summer between my first and second years of medical school. We worked on a pediatric malaria project, which was very interesting.” At that point, she wasn't sure of her future specialization, but she “liked the thinking process behind internal medicine.” She was one of just two residents per year selected for the Stanford Internal Medicine and Global Health residency program. “As Global Health Internal Medicine residents, we did more elective time in things like tropical medicine, participated in global health journal clubs, and I spent a total of 12 weeks overseas at the Uganda Cancer Institute in Kampala.” Pumpalova said that, as she looked back, she realized “going to sub-Saharan Africa as a resident, as opposed to a medical student, was very different. By the time I went, I had already been taking care of patients at Stanford for a year and a half. Knowing what we can offer patients here and seeing the limitations of what could be offered in Uganda, made it challenging to provide direct patient care in East Africa. It was difficult to see very advanced disease in a lot of very young patients and truly experience the limitations of what could be offered to them there. It was not because of a lack of knowledge from the provider side, but a lack of access to most medications that are available in richer countries such as the U.S. and throughout Western Europe. It's one thing to know that conceptually and intellectually—we all know that access to cancer drugs is a big problem. But seeing it upfront and personal is different and jarring—a culture shock.” Cancer Care in Africa While in Uganda, Pumpalova worked at Mulago Hospital, one of the largest public hospitals in East Africa. “There are some medications that patients can access for free in the public hospital, but the vast majority of cancer drugs require payment out-of-pocket,” she explained. “There are some limited cancer drugs, very standard chemotherapy that, in theory, is available free of charge on formulary, but it is very limited and they often run out. “Oftentimes, patients and families are given a prescription and told to buy the drugs in a private pharmacy and bring them back to the infusion center. You run into these issues where maybe the family is able to pay for a few months and then they don't have enough money to continue treatment. Then a few months later, they may be able to pay for a bit more.” Pumpalova said there is a misconception by doctors in the U.S. that patients with cancer in sub-Saharan Africa get no treatment at all. “Certainly for people who cannot pay, that may be true in some instances. But what is also true, and less well-understood by people who haven't practiced in these settings, is that there are actually a lot of people who are spending down their family's savings to get chemotherapy, and often this is in the palliative setting and not curative. “Some of the work that I did in Uganda was trying to determine if patients with metastatic or Stage IV cancer understand their diagnosis, and that the chemo that they're getting, for the most part, is with palliative intent,” she explained. “We found that oftentimes they did think that this treatment was going to cure them.” Currently, Pumpalova is focusing her global health research work in South Africa, one of the richest countries in sub-Saharan Africa. “South Africa has a very well-developed public health care sector, which serves 85 percent of the population, and many chemotherapy drugs are available to patients free of charge. Although cancer care in South Africa is still limited compared to what we're able to offer in the United States, even in the curative-intent setting, access is much better than in most of sub-Saharan Africa, including Uganda.” If South Africa is considered a rich country, why is access to life-saving cancer treatments still limited? It mostly comes down to cost. “The World Health Organization compiles an Essential Medicines list—something that gets debated and discussed a lot—naming which drugs are life-saving to the point where every country should really have them available. There are a number of chemotherapy drugs on that list,” detailed Pumpalova. “Countries then look at that WHO list and make their own calculation as to what they can afford to provide. It really has to do with the cost of drugs and then how much money the government is able to put toward chemotherapy drugs versus other things—or just health care in general versus all the other things they're trying to fund.” Access & Outcomes One might reasonably conclude that lack of access to cancer drugs translates to poorer patient outcomes. “Yes,” Pumpalova confirmed, “cancer outcomes are much worse in sub-Saharan Africa. A patient with Stage III breast cancer in sub-Saharan Africa will have a much shorter overall survival compared to a similar patient in the United States. This is not only because patients in South Africa often cannot access the same drugs as patients in the U.S. Patients also face many barriers to accessing health care, and there is very little cancer screening, so patients tend to be diagnosed later in their disease. “One of the studies I've been part of—a cohort study that is a collaboration between Columbia and the University of Witwatersrand in Johannesburg—is following a very large cohort of women with breast cancer in Johannesburg and in Durban. There are now almost 5,000 cases in this cohort study, and just a very small percent—less than 5 percent—are diagnosed with Stage I breast cancer,” Pumpalova said. “Stage I breast cancer almost doesn't exist outside of countries where we screen for breast cancer in an organized way. In the United States, the overwhelming majority of patients are diagnosed with Stage I or Stage II breast cancer. And even when we match stage for stage, the breast cancer outcomes in sub-Saharan Africa are worse.” In her clinical work, Pumpalova sees patients with lower gastrointestinal cancers. “I'm a GI oncologist with a specific focus on colorectal and anal cancer. My research now focuses on the best way to diagnose colorectal cancer at an earlier stage in low-resource settings,” she told Oncology Times. “We know that colorectal cancer incidence and prevalence are highest in the most economically developed countries, like the U.S., Australia, and countries in Western Europe. Colorectal cancer is a clear marker of an epidemiologic transition, and its incidence and prevalence increase with economic development. As countries become more economically strong, their population becomes more sedentary, more obese, and consumes more alcohol and more red meat. All of these are risk factors for colorectal cancer. “So, as countries become more economically developed, we see an increase in colorectal cancer incidence. Countries like South Africa, which is rapidly developing from an economic standpoint, are very interesting for me. Although colorectal cancer incidence and prevalence in such countries is currently much lower than it is in the United States, the rate of rise in these countries is very high. They're on a trajectory where colorectal cancer will become a more important and prevalent cancer over time. My research focuses on what the early signs and symptoms of colorectal cancer are, and what we can do from an implementation science standpoint to help clinicians identify and diagnose patients earlier, when their disease is still curable.” Toward that end, Pumpalova and fellow researchers are characterizing how most patients in places like South Africa present when they are diagnosed with colorectal cancer. “Some of our work is descriptive—at what age do patients with colorectal cancer present? With what symptoms do they present? What are the barriers for them? If they've had symptoms for 6 months or 12 months, what are the reasons they've waited as long as they did to present?” So far, it appears that presentation “is very similar to what we see here in the United States. There's bleeding in the stool, pain in the abdomen, changes in stool or bowel habits, weight loss, and anemia. Those tend to be the most common presentations. However, the delays to presentation are quite staggering, with many patients waiting 6-12 months prior to presenting for care.” Screening Opportunities Pumpalova further explained that, unlike the United States where screening for colorectal cancer is common, there is no such screening in South Africa or any country in sub-Saharan Africa. “One of the studies that I have initiated in South Africa investigates whether we can use the stool FIT test (fecal immunochemical test)—which detects a microscopic amount of blood in the stool—to identify which symptomatic patients in South Africa are most likely to be diagnosed with colorectal cancer and to prioritize them for diagnostic colonoscopy. There's limited access to people who can do colonoscopies in South Africa and a lot of low- and middle-income countries, so trying to figure which patients need a colonoscopy most urgently is imperative. “In the U.S., we use FIT to screen for colorectal cancer in asymptomatic patients, but there is excellent data from the UK and Canada that this low-cost test can be used to triage symptomatic patients as well. The main question of our ongoing study: Can we use a combination of FIT and the symptoms that patients are presenting with to come up with an algorithm that tells us which patients should be prioritized for a colonoscopy?” It's still too soon to know, said Pumpalova, noting that the study has just opened with an enrollment of three patients in the city of Durban. “We're also opening the study in Johannesburg. We're taking patients who are scheduled for colonoscopy, interviewing them about their symptoms, and doing the stool test to see if we can predict what is going to be found on the colonoscopy.” The study is being done in collaboration with the University of KwaZulu-Natal in Durban and the University of Witwatersrand in Johannesburg, co-led by Pumpalova and collaborators at those institutions. She said it is also important to expand the capacity for more colonoscopies and train more people on how to do that procedure in sub-Saharan Africa. “There is no question that the capacity for colonoscopy in the public hospitals in South Africa should increase. This is imperative, especially as colorectal cancer incidence increases, and must happen in order to start thinking about organized colorectal cancer screening one day.” However, it is also critical to get as much data as possible on how well the cheap stool tests work in that setting. “It is something that has not been well-studied, but has the potential to improve outcomes among patients with colorectal cancer without increasing costs significantly,” she noted. “Eventually these tests will also probably be an important part of colorectal cancer screening programs.” What Can We Learn From Africa? Asked if there are correlations that can be drawn between cancer care in Africa and the United States, Pumpalova stressed, “Yes, absolutely. There's a lot that we can learn from studying cancer care delivery in low-resource settings. We have a lot of low-resource settings here in the United States, too, and we also have a lot of patient populations, especially minority populations, that are very hesitant to undergo procedures like colonoscopies. I think in the United States, we really haven't done a great job of using lower-cost modalities to try to increase colorectal cancer screening rates. Our screening rates for colorectal cancer in the United States are below what they are in a lot of Western European and Scandinavian countries. They're below what they are in Canada. We can do better. In the U.S., we also don't think enough about cost. Things are only feasible if they can be paid for in a low-resource setting, so cost must be at the center of any intervention for it to succeed. I think we can learn a lot from this approach.” Pointing to another issue that has international correlations, Pumpalova stated, “The other really interesting question in colorectal cancer specifically has actually to do with rectal cancer. Colorectal cancer, especially rectal cancer, is increasing in incidence in the United States, especially among younger patients—less than 45 years old, patients who are too young for screening, essentially. Although we have observed this trend, we don't understand why it is happening. “There are large, ongoing studies and a lot of different people trying to investigate this question. In much of sub-Saharan Africa, the population is very young and in many cohort studies rectal cancer makes up 50 percent of all colorectal cancers, compared to approximately 30 percent in the United States. I think there's a lot that can be done from a tumor profiling/genomics/genetics standpoint using samples from African populations to help us understand the rise in rectal cancer both here in the United States and globally.” Are there any hypotheses as to why colorectal cancer, and especially rectal cancer, incidence is increasing in the United States? “There are many,” answered the clinician researcher. “People think that it's a birth cohort effect, that there's some exposure that patients who now are in their late 30s/early 40s had as young adults or as children. People have hypothesized that antibiotics could be part of it. People are thinking about diet and about other environmental exposures. “There's nothing that's a slam dunk and no clear answer as to what is causing it. We've done very little with studying of African populations and other non-White populations in terms of genetic predisposition to colorectal cancer. I think there's a lot that we can learn from doing these types of studies with a more diverse population to try to understand if there also is an inherited genetic component that's driving the colorectal cancers that we're seeing worldwide. “One of the ways I hope our field will change during the course of my career is to put a little less focus on novel drug discovery that is only going to benefit the wealthiest patients in the wealthiest countries,” she said thoughtfully. “I'm hopeful we will go in a direction where we're also designing clinical trials that help us understand how to take care of large populations outside the Unites States, as well as within, as opposed to focusing on drugs that benefit a small slice of overall populations. Opening trials in different types of settings will be important to equitably treat cancer patients all over the world.” Valerie Neff Newitt is a contributing writer.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.