Stepping into the Center for Pathology and Molecular Biology at K Hospital, one is immediately enveloped by the distinct scent of formalin and xylene. This is where doctors tirelessly analyze tissue samples, providing crucial diagnoses that guide cancer treatment.

The unseen role of pathologists in medicine

While they do not directly treat patients, pathologists and laboratory specialists play an essential role in the healthcare system. They are the ones who "name the disease," enabling clinicians to make informed treatment decisions.

As Vietnam marks the 70th anniversary of National Doctors' Day (February 27, 1955 – February 27, 2025), VietNamNet presents a series titled The Silent Work of the Medical Profession, sharing heartfelt stories from those who dedicate their lives to medicine behind the scenes.

One such case is Nguyen Hong Hanh (name changed), a 22-year-old woman from Bac Giang. In early 2024, she noticed a small lump on her chest, which was initially diagnosed as a fibroadenoma. By August, the lump had become firmer, painful, and inflamed. Suspicious of the changes, doctors referred her to K Hospital in Hanoi.

Following clinical examinations, MRI scans, and a biopsy, her tumor was found to have aggressive characteristics. Pathological analysis pointed to three possible diagnoses: diffuse large B-cell lymphoma, Burkitt lymphoma, or anaplastic large cell lymphoma.

To determine the exact nature of the tumor, pathologists performed immunohistochemical staining. The results confirmed anaplastic large cell lymphoma. Thanks to precise pathology, doctors could assess the cancer stage and establish the most effective treatment plan.

Another patient, Vo Ngoc Tuyen from Da Nang, was initially diagnosed at two different hospitals - one suggested an infection requiring antibiotics, while the other diagnosed rhabdomyosarcoma (a malignant tumor), advising leg amputation.

Seeking a definitive diagnosis, her family sent the biopsy slides to K Hospital, where pathology results revealed it was lymphoma. This diagnosis allowed her to undergo chemotherapy instead of unnecessary limb amputation.

The critical role of pathology in cancer diagnosis

Professor Nguyen Chan Hung, honorary president of the Vietnam Cancer Association, stresses the importance of pathology in avoiding false diagnoses.

A false positive - misdiagnosing a healthy person with cancer - can cause unnecessary distress and medical intervention, while a false negative delays crucial treatment. This is why pathology is considered the "gold standard" for cancer diagnosis.

At K Hospital’s pathology center in Tan Trieu, Thanh Tri, Hanoi, the stark contrast between the overcrowded clinical wards and the silent, focused atmosphere of the pathology lab is striking. Here, doctors and technicians work diligently with tissue samples, slides, and chemicals, deciphering the mysteries of disease.

Dr. Truong Thi Hoang Lan, deputy director of the center, explains that due to constant exposure to hazardous chemicals and infectious samples, pathologists receive higher occupational hazard allowances than other medical professionals.

A high-stakes precision process

The center operates with nearly 50 medical staff, including 20 doctors and a team of technicians and biologists. It specializes in advanced diagnostic techniques, including molecular biology tests to identify genetic mutations for targeted cancer therapy. In addition to histopathology, immunohistochemistry, and cytology are also key services.

Each day, 20 pathologists analyze between 1,800 and 2,000 slides from 380 to 400 biopsy samples.

In the macroscopic pathology room, countless tissue samples arrive from surgical departments, including specimens from the stomach, intestines, lungs, liver, brain, breast, uterus, and bones.

Doctors humorously refer to the specimen processing area as the "kitchen" due to the abundance of scalpels, scissors, and cutting boards used to prepare samples. Every tissue sample undergoes meticulous examination to ensure accurate diagnosis.

Dr. Lan points to an ovarian cancer case where surgeons had performed a complete hysterectomy, removing lymph nodes and both ovaries. Pathologists now faced the crucial task of assessing every part of the specimen to determine the extent of the disease.

Each lymph node specimen is sectioned into 5 to 10 blocks, depending on its size and location. A single tumor may require three to five blocks, sometimes more, to ensure precise staging and diagnosis.

"Any mistake in sample processing can lead to diagnostic errors, impacting the assessment of cancer progression," Dr. Lan warns.

The long road to a final diagnosis

In K Hospital’s pathology reading room, specialists determine the ultimate diagnosis - benign or malignant.

Dr. Lan explains that most pathology cases take two to five days to finalize, though complex cases may require additional time. If the initial findings are unclear, pathologists must repeat staining and reanalyze slides multiple times.

"Unlike other laboratory tests, such as biochemistry or hematology, which rely on automated machines, pathology depends entirely on the doctor’s expertise and experience," she says.

Cancer pathology presents unique challenges due to the heterogeneous nature of tumors. A single tumor may contain multiple types of abnormal cells, making diagnosis difficult. In such cases, immunohistochemistry is essential in distinguishing between cancerous and benign tissues.

With over 20 years of experience, Dr. Lan has faced moments of hesitation while writing pathology reports. Determining whether a tumor is benign or malignant is a life-altering decision for patients, especially young individuals.

A precise yet imperfect science

While pathology remains the gold standard in cancer diagnosis, false negatives and false positives can still occur. Dr. Lan emphasizes that accuracy heavily depends on how biopsy samples are handled.

Ideally, surgical specimens should be preserved in 10% neutral formalin within 30 minutes of removal. However, delays in fixation or improper sample handling can compromise diagnostic accuracy.

To minimize errors, pathologists, surgeons, and radiologists must work as a team, ensuring the most reliable diagnosis and treatment strategy.

As the largest cancer hospital in northern Vietnam, K Hospital examines and treats 400,000 to 500,000 patients annually. The pathology center’s 50 dedicated staff members work tirelessly to support clinical departments, ensuring that every cancer diagnosis is as accurate as possible.

Phuong Thuy