Karachi: Esophageal cancer has emerged as the leading cancer among adult men in Balochistan and the second most common malignancy among adult women, indicating a disease pattern distinct from that reported in Karachi and other parts of Pakistan, a new study has found.
The study, published in the Journal of the College of Physicians and Surgeons Pakistan, reviewed 16,342 biopsy specimens received from across Balochistan between 2021 and 2024, of which 5,145 were confirmed as malignant.
Researchers from the Aga Khan University Hospital, Karachi, and Aria Institute of Medical Sciences, Quetta, found that men accounted for 52 percent of the confirmed cancer cases and women for 48 percent.
Among 2,438 adult male cancer patients aged 20 years and above, 425, or 17.4 percent, had esophageal cancer. Stomach cancer was the second most common malignancy, reported in 351 men or 14.4 percent.
Cancers of the large bowel, rectum and anal canal ranked third, with 225 cases or 9.2 percent, followed closely by urinary bladder cancer with 223 cases, or 9.1 percent.
The researchers said the pattern differed from national and Karachi cancer-registry data, where oral cavity cancer is more commonly reported as the leading malignancy among adult men. In Balochistan, esophageal cancer was reported nearly four times as frequently as oral cavity cancer among adult men.
Breast cancer remained the most common malignancy among women. Of 2,351 adult female cancer patients, 526, or 22.4 percent, were diagnosed with breast cancer.
However, esophageal cancer was also highly prevalent among women, accounting for 434 cases or 18.5 percent. Cancers of the large bowel, rectum and anal canal followed with 125 cases, or 5.3 percent, while oral cavity cancer was reported in 113 women, or 4.8 percent.
The high frequency of esophageal cancer among both men and women may indicate common environmental, dietary or lifestyle-related risk factors in the province, the researchers said.
They identified the use of very hot tea and other hot beverages, particularly in rural communities, as one possible contributing factor. Regular consumption of extremely hot drinks may repeatedly injure the lining of the esophagus and increase cancer risk over time.
Other possible factors cited in the study included preserved foods, particularly salted and dried meat, low consumption of fresh fruits and vegetables, dietary carcinogens, opium use and environmental exposures. The researchers, however, did not establish any of these as definitive causes.
Colorectal cancer also emerged as an important concern, with 225 cases among adult men and 125 among adult women. The study said urbanisation, greater consumption of processed foods, physical inactivity and increasing obesity could be associated with the growing burden of colorectal cancer.
Children and adolescents constituted seven percent of all confirmed cancer cases. Their cancer profile differed from that of adults, with brain tumours and different forms of lymphoma among the more prominent malignancies.
The authors cautioned that the findings were based on pathology specimens and may not represent the full cancer burden in Balochistan, where diagnostic and treatment facilities remain limited. Many patients may not reach facilities capable of obtaining or reporting a biopsy.
They said Pakistan still lacked a comprehensive national cancer registry, limiting the ability of health authorities to accurately assess cancer trends and plan prevention, screening and treatment services.
The researchers called for stronger cancer-registration systems, population-based and multicentre studies, and better integration of clinical, radiological and pathology records to develop a clearer picture of the disease burden.
They said the findings underscored the need for region-specific cancer-control strategies in Balochistan, particularly research and prevention efforts focused on esophageal cancer.