The recent news of the sudden passing of the well-known actor, Tzu-Chun Fu, due to suspected acute leukemia complicated by pneumonia and sepsis has shocked the public. Although we have no way of knowing the details of his condition, this tragic outcome should serve as a loud wake-up call, awakening many modern people who hustle for their lives and work but forget to listen to their bodies. The "silent" and "ruthless" nature of diseases reminds us that we must re-examine our health management concepts, but we can also take this opportunity to understand this often-stigmatized disease: leukemia.



Leukemia is a cancer that occurs in the blood-forming organ—the bone marrow. Our bone marrow is the manufacturing factory for blood cells, producing red blood cells that carry oxygen, white blood cells that fight foreign pathogens, and platelets responsible for blood clotting. When mutated hematopoietic stem cells in the bone marrow begin to uncontrollably proliferate abnormal, immature white blood cells (i.e., cancer cells), these leukemia cells will occupy a massive amount of space in the bone marrow, causing normal blood cells to be unable to grow properly, which in turn affects the functioning of organs throughout the body and immune defense capabilities.



Clinically, leukemia can be divided into "acute" and "chronic" based on the "speed of disease progression," and the prognosis and treatment for both are vastly different. Acute leukemia is more like the blood cancer people generally imagine; the disease progresses rapidly and fiercely, and due to a significant decrease in normal blood cells, symptoms like infections and bleeding easily occur. Treatment primarily relies on chemotherapy, and depending on the disease prognosis, a hematopoietic stem cell transplant may be required. In contrast, chronic leukemia progresses more slowly; there may be no symptoms at all in the early stages, and many patients even discover it entirely by accident through routine health check-up blood tests. Current treatments for chronic leukemia mainly involve oral targeted therapies, and early-stage chronic lymphocytic leukemia can even be continuously observed without the need for treatment, which is vastly different from the general impression of blood cancers. But even with acute leukemia, although the chemotherapy process is more arduous, compared to other difficult-to-cure systemic metastatic cancers, acute leukemia has about a 40% chance of a cure. It is actually a highly treatable cancer, very different from the stereotype that getting blood cancer is a terminal illness. The recent case of entertainer Mr. Yu-Lin Shen, who returned to work and served as a blood cancer ambassador after undergoing treatment for acute leukemia last year, is the best example.



Following such news, many media outlets often remind the public to watch out for related symptoms, such as unexplained fever, bruises, inexplicable bone pain, or a lingering sense of extreme fatigue. It is true that leukemia might present these symptoms (though not necessarily all of them); however, relying solely on symptoms to determine if one has leukemia (or any other disease) is highly inappropriate and difficult for the general public. Because these symptoms are often "non-specific," meaning many other conditions could also have these types of symptoms. For instance, fatigue and a mild fever might just be a common cold or overwork. If people immediately associate these common symptoms with leukemia or certain diseases, it easily causes unnecessary panic and anxiety. Conversely, the other extreme is "over-neglect," constantly thinking that one is just recently tired or has poor immunity, casually taking over-the-counter medications, or choosing to endure it, resulting in missing the golden window for medical attention and treatment. Therefore, a more practical approach is to establish a correct medical concept: "When the body experiences persistent, unexplained, and lingering abnormal changes, seeking professional medical assistance as early as possible is the most crucial step". Leaving the responsibility of diagnosis to professional medical personnel and scientific testing equipment not only avoids pointless psychological torment but also precisely captures the subtle signals sent by the disease. As for leukemia, besides the commonly mentioned high or low blood cell counts, clinicians actually often observe the "white blood cell differential count," determining the cause of blood cell changes by analyzing whether there are abnormal white blood cells and their proportions. Because leukemia is right there in the blood, theoretically, a blood test can reveal the clues; it is actually a cancer that is not easily missed in diagnosis, provided the premise is not to avoid seeing a doctor.



Furthermore, the diagnosis and treatment of leukemia have officially entered a new era of "precision medicine," and next-generation sequencing (NGS) plays an irreplaceable, critical guiding role (Figure 1). Through NGS technology, dozens or even hundreds of genes related to leukemia (such as FLT3, NPM1, CEBPA, TP53, etc.) can be comprehensively tested at once in a short time. This is extremely important for judging the prognosis (which affects whether a hematopoietic stem cell transplant is needed) and choosing many target therapies. And because of the high sensitivity of NGS, it can also be used to monitor the presence of a small number of cancer cells after treatment. Such concepts and technologies have now been applied to the treatment of various other cancers as well, gradually becoming indispensable information for current cancer treatment.



Regarding treatment, although acute leukemia has a high chance of being cured through chemotherapy, the treatment risks are indeed too high for the elderly or patients with other chronic diseases like cardiopulmonary issues, which also limits the treatment efficacy for these patients. Over the past decade, the emergence of many targeted drugs has shed a light to the treatment of elderly patients. Taking acute myeloid leukemia as an example, using the targeted drug venetoclax combined with low-dose chemotherapy or hypomethylating agents can significantly reduce side effects while achieving efficacy similar to systemic chemotherapy, allowing populations traditionally unsuited for chemotherapy to achieve a major breakthrough in treatment (Figure 2). Combined with NGS test results, doctors can also consider combining other targeted drugs, and in the future, it may even have the opportunity to replace some chemotherapy, further reducing treatment risks (you can also refer to hospital newsletters issue 252 from November 2020 and issue 310 from September 2025 for related introductions to acute leukemia).



Returning to this incredibly regrettable news event, although the disease progressed very quickly and there was not even time to complete a definitive diagnosis, most of the time, leukemia is not as terrifying as imagined. Instead, with current medical advancements, there are increasing chances to fight against it. At the same time, however, it also reminds us that the fragility of life always leaves people feeling caught off guard and helpless. Regardless of age, we should establish a correct concept of seeking medical attention; paying attention to persistent abnormal symptoms and seeing a doctor promptly are the essential keys to protecting health.