Health Derailed in Houston After Authorities Confirm Liver Cancer Cluster

HOUSTON, TX. – Rates of bile duct other biliary cancers are significantly elevated in the Kashmere Gardens (fifth ward) neighborhood of Houston, Texas, according to the Texas Department of State Health Services.¹ Considering the higher-than-average rate of liver cancer in Texas as a whole², it was unexpected that the Kashmere Gardens cluster would be linked to environmental issues.

Texas Department of State Health Services Investigation #18002 assessed 37 census tracts within the city of Houston between 2010 and 2015. The goal was to determine if rates of cancer in Houston statistically exceeded the rates in Texas. The expected number of intrahepatic bile duct cancer cases in Houston was 136.1, and the number observed was 163, showing a standardized incidence ratio (SIR) of 1.20 (95% CI, 1.02–1.40). For other biliary cancer, the expected number was 212.4, but 235 were observed (SIR, 1.11; 95% CI, 0.97–1.26).

In comparison, the number of intrahepatic bile duct cancers expected in Houston was 9.2. The number observed in Houston was 16 (SIR, 1.74; 95% CI, 0.99-2.82). The number of other biliary cancer expected in Houston was 13.9, but 12 were observed (SIR, 0.87; 95% CI, 0.45-1.51).

“In the city of Houston as a whole, the observed number of all-age intrahepatic bile duct cancers was statistically significantly, greater than expected, and the number of other biliary cancers among all ages was within the range of what is expected based on cancer rates in Texas,” wrote the Texas Department of State Health Services in the report.¹

“Liver cancer is going up all over the country, and it is 1 of the highest-grade cancers in Texas, compared [with] other parts of the country. This is especially in including the valley, Houston, and the suburbs. Any disease leading to cirrhosis can lead to liver cancer. That includes alcohol, other drugs, and toxins, including fatty liver. Believe it or not, in Texas, the percentage of patients with obesity and fatty liver is huge. Almost 40% of the adult population in Texas has fatty liver and some of them can progress to cirrhosis and it can lead to cancer. Apart from that, there are environmental toxins that can lead to liver cancer. The cluster in Houston’s fifth ward is related to pollutants that can lead to many types of cancer aside from liver cancer,” said Prasun K. Jalal, MD, Stan and Sue Partee Endowed Chair in Hepatology and assistant professor in Medicine and Surgery at Baylor College of Medicine, in an interview with Targeted Oncology™.

In the Kashmere Gardens neighborhood, other cancers identified include lung/bronchus, esophagus, and larynx cancers, as well as childhood leukemia. However, liver cancer it the only malignancy found in high number in all the fifth ward census tracts.²

Investigating Cause and Effect

Multiple efforts were made by local government from 2019 to 2022 to develop a better understanding of the health issue in Kashmere Gardens, including a survey, and health and wellness fair. On August 12, 2022, the Texas Department of State Health Service hosted a Subject Matter Experts Conference Call with multiple experts from Houston’s hospitals, universities, activist organizations, and health services staff.⁴

The conference call aimed to determine the feasibility of conducting an epidemiologic study in Kashmere Gardens and other neighborhoods surrounding a former creosote wood treating facility. The study would focus on a 17-year-period (2000-2016).

During the call, experts raised questions about the patients’ chemical exposure, the larger than normal numbers of liver cancer cases in census tract 2112 (a part of Kashmere Gardens), developing a hypothesis for a future study, study design, and feasibility. Ultimately, the experts collectively determined that an epidemiolocal study was not feasible.

“We at the National Cancer Institute are asked quite regularly as is CDC to investigate a cluster. Which cancer clusters we investigate depend on what the true profile or balance is when we look at cancer registries, it’s not just about whether every third person gets cancer. There are familial issues, environmental issues, and when you look at clusters, 1 of the key things is trying to figure out whether it is statistically different than what you would expect in particular pockets,” explain Stephen J. Chanock, MD, director Division of Cancer Epidemiology & Genetics, in an interview with Targeted Oncology.

“Liver cancer is a very interesting disease, we are learning a lot about the number of experts in our program who are focusing on this and have predisposing causes like increase in body mass index, fibrotic changes in the liver, and various viruses. I think one needs to investigate and look at how you put that whole puzzle together. It’s not only the fact that you see an increase in numbers in a particular place,” Chanock added.

An addendum released by the Texas Department of State Health Services following the call with subject matter experts determined this an epidemiologic study because there are many risk factors of liver cancer, other care to consider, and limitations based on residents’ exposure to certain chemicals. Further, the experts noted that questions remain about the disease latency and lack of information regarding residential history, the environmental data are unclear, and the study would be time intensive.

The cause of the cluster, however, continues to be investigated.

After testing the drinking water, storm sewer, surface water, and oil, the city of Houston released notice that dioxins were found in the soil in addition to the creosote previously identified in the surface water. Dioxins are known to alter liver function and these chemicals, in addition to other dangerous substances, were identified in the cluster area. Because these toxins were found near the intersection of Liberty Road and Lavender Street in the Kashmere Gardens neighborhood, the City of Houston cited Union Pacific Railroad’s creosote wood treatment facility as the source of the chemicals.

The Environmental Protection Agency also completed a review of the area and the organization's concerns were noted in a letter to Union Pacific Railroad. This action led to a response from United States Congress.⁵

"I am pleased to thank EPA Administrator Michael Regan, the Environmental Protection Agency, and the Biden Administration for these important steps forward to help the people in my Congressional District, living in Kashmere Gardens, 5th Ward and other Northeast areas of Houston and Harris County that comprise the 18th Congressional District. This announcement today is going to change lives. Over the past years I have been holding meetings, and engaging with state and federal officials repeatedly, and meeting cancer victims while listening to the stories of families who lost loved to cancer and other diseases over the generations. We are desperate for relief. I have been disappointed by the unwillingness of previous Administrations to act to protect residents. Now that has changed with the Biden Administration,” said Congresswoman Sheila Jackson Lee, in a press release.⁵

Finally, the City of Houston announced their intent to bring suit against Union Pacific Railroad in a 90-day notice letter on July 27, 2022.⁶

Treatment Options

According to the Texas Department of State Health Services, many Kashmere Gardens residents have moved due to impact of the cancer cluster and other health issues believed to be related to the toxic chemical presence in the area. For those who remain, community oncologists play a large role in their lives. Also, a growing treatment landscape offers hope to oncologists who are treating these patients, according to Jalal.

“We try to minimize chemotherapy in early or intermediate stage liver cancer because we can cure this with locoregional treatment, including ablation to microwave radiation radiofrequency ablation, or going through the groin, blood vessels, etc. We can do a lot of other stuff before we jump into chemotherapy. Of course, systemic therapy is important, and we can use it in conjunction with it with all the modalities I've mentioned,” added Jalal.

“It's important to note that with liver cancer diagnosis, we do not need to biopsy the liver all the time. [Most of the] time, the diagnosis is made by good scan. We should avoid invasive testing in cases that patients need surgery or transplant. Now, there are multiple chemotherapeutic agents, but there are also other therapies. One group is called multikinase inhibitors that are working at multiple levels of the kinase pathway, which cause inflation of cancer tissue. One of the priority drugs is sorafenib [Nexavar]. Sorafenib increases survival. It had some side effects, so we always looking for newer drugs. The other drug we used is called lenvatinib [Lenvima]. It is a similar drug, but [with less toxicity]. But since these drug approvals, we have advanced further. We now have cabozantinib [Cabomety]. So, there are many liver cancer drugs available, which are targeted therapies and immunotherapy,” said Jalal.

Treating liver cancer can be a challenge for oncologist, Jalal noted. This is especially true for those treating in a cancer cluster area.

“The biggest challenge we face is awareness. Liver cancer is 1 of the cancers that is pretty unique because if it is diagnosed early, it can be treated and can be cured. That means in the community, people need to be aware of it. That includes primary care physicians, gastroenterologists, family physicians, and other specialties. If someone has liver disease, like fatty liver, or whether it is hepatitis C or B or alcohol induced, and their liver is developing cirrhosis, they need to be set to deliver centers where they can manage for any complications. They may be patients receiving care in the community on in oncology centers. We usually put them on surveillance because the majority of the liver cancers come from cirrhosis, which is scarring, but not a lot is from liver disease. And [these patients] don't always have pain. They don't have any symptoms, and commonly, their disease missed or overlooked because by the time they're having symptoms of pain, it's too late. If you know that you have a population which are more prone to have chronic liver disease and that can lead to cirrhosis or liver cancer, put them on surveillance,” Jalal advised.

Another important part of treating patients in Houston’s cancer cluster area is developing multidisciplinary teams to ensure all the patient’s need are met.

“At Baylor St. Luke's Medical Center, especially in the oncology center, we all work together in a multidisciplinary team. We have surgeons, transplant hepatologists, liver specialists, and other gastrointestinal physicians. We have radiologists, interventional radiologists and we also have coordinators for the transplant, social workers, then oncologists who specialized in liver cancer. The whole teams meets once a week, discusses all the patients who are potentially planning for treatment, and we decide the best course of treatment,” explained Jalal. “I think increasing awareness, early diagnosis, and getting the patient the right place will change the landscape. Again, coming back to the greater Houston area of Texas, liver cancer is huge. It's a curable disease. Increasing awareness is our challenge, and we need to work together to achieve that goal.”

_REFERENCES:

_{1. Assessment of Houston, Texas the Occurrence of Cancer (2010-2015). Texas Department of State Health Services. Published January 2, 2019. Accessed October 31, 2022. https://www.dshs.texas.gov/epitox/reports/Houston-CSum-18002.xls}

_{2. El-Serag HB, Sardell R, Thrift AP, et al. Texas has the highest hepatocellular carcinoma incidence rates in the USA. Dig Dis Sci. 202;66(3):912-916. doi: 10.1007/s10620-020-06231-4}

_{3. Assessment of the Occurrence of Cancer Supplemental Assessment Houston, Texas 2000-2016. Texas Department of State Health Services. Published January 4, 2021. Accessed October 31, 2022. https://dshs.texas.gov/epitox/CancerClusters/Supplemental-Assessment-of-the-Occurrence-of-Cancer-Houston-Texas-2000-2016.pdf}

_{4. Meeting Summary Subject Matter Experts Conference Call Assessment of the Occurrence of Cancer, Houston, Texas. Texas Department of State Health Services. Published August 17, 2022. Accessed October 31, 2022. https://www.houstonhealth.org/media/3326/download}

_{5. EPA administrator Regan announces bold actions to protect communities following the Journey to Justice Tour. News release. EPA. Published January 26, 2022. Accessed October 31, 2022. https://www.epa.gov/newsreleases/epa-administrator-regan-announces-bold-actions-protect-communities-following-journey}

_{6. 90‐Day Notice of Intent to Sue under the Resource Conservation and Recovery Act. City of Houston. Published July 27, 2022. Accessed October 31, 2022. https://www.houstonhealth.org/media/5456/download}