Histopathological Laboratory

This service makes analysis of the tissue structure to determine possible causes of diseases. In this laboratory the following procedures are performed: cytology, histology, pathology and immunohistochemistry.


*Based and Modified From:

  • FAQ: MDAnderson Cancer Center-Pathology and Medicine Laboratory. Laboratory.
  • What is Pathology?: Royal College of Pathologist.
  • Medicine is Pathology: The Royal College of Pathologist of Australasia.

What is Pathology?

It is a specialty of medicine that studies the organs and tissues to help determine the causes and effects of a particular disease.
The findings of the pathologist are essential for medical diagnostics, patient management and research. Pathology saves lives by helping other physicians decide the appropriate treatment. Surgeons and clinicians depend on knowledge, diagnostic skills and advice of Pathologists whose answer is usually final.

What kind of training and specialization does a Pathologist have?

A pathologist is a doctor who must have a fourth level bachelor's degree.
During the surgery the surgeon awaits for the pathologist's diagnosing before deciding how much tumor will be extracted, if it exists and what type of treatment the patient needs. The pathologist's job can save the patient's life and very often, the patient doesn't meet them.

If I have cancer, do I need a Pathologist?

Yes, a pathologist is a specialist who identifies diseases by studying cells and tissues under a microscope. Pathology is a medical specialty which aims to provide a definitive diagnosis of many different diseases, including cancer. Usually the pathologist treats the patient whose treating physician performed a biopsy for its pathological study. The physician who refers the patient is usually the treating doctor. The pathologist, whom most patients never know, is like the doctor's doctor.

What does a Pathologist do?

The Pathologist examines body tissues under a microscope to see what kind of abnormalities are in the tissue samples. The pathologist writes a report detailing the diagnosis. The information contained in the report helps the doctor decide the action plan.

What is a Biopsy?

It is the removal of a cellular or tissue sample for examination though a microscope. When the sample is obtained by a needle, the procedure is called a needle biopsy or fine needle aspiration.

How big is the sample taken?

If it's a biopsy the sample taken is very small. However the sample must be large enough to represent the abnormality.

How is the tissue sample saved?

The tissue is fixed in formalin and is then sealed inside a block of wax. It is transported to a laboratory where they cut it into extremely thin slices with a special machine. Technologists use dyes to stain the sample so they can see the cells under a microscope. Eventually depending to the technical need the tissue is frozen.

Do they name the patient's samples before taking them from the operating room?

Yes, immediately. Each sample is assigned a unique number which then reflects on the pathology report.

How does the Pathologist handle this under a microscope if the sample is so small?

The technologist places the fine cut of the sample on a glass slide and seals it with another slide. This is called a Pathology slide.

Is it easy to determine the type of cancer?

Usually, most cases are straightforward. However there are some cases where more testing and special procedures are needed including immunohistochemistry and electron microscopy to perform a final diagnosis.

Will more than one Pathologist examine my slides?

Very often more than one pathologist examines cases here in the Pathology Department of Hospital Metropolitano. We also have weekly tumor conferences where several pathologists, oncologists, surgeons, and really all the specialists involved in patient care talk in detail about the cases.

What happens when someone disagrees?

If the Pathologists disagree, they meet and talk about all the aspects of the case and reach a consensus.

How long do they keep the slides?

The slides remain in the permanent file of the Hospital Metropolitano Pathology Service and may be examined at anytime and anywhere.

What is a Surgical Pathology report?

It's the report that identifies the tissue sample as belonging to a specific patient and details the diagnosis.

Does a Pathologist ever talk to the patients?


Can a cancer diagnosis be made with a blood test?

In some cases, in leukemia for example, diagnosis can be performed with a blood sample. There are some cancers in which blood helps with the diagnosis (prostate cancer). However, for most cancers, a tissue sample is needed.

How many different cancers are there? What are their names?

Cancer is a group of more than 100 diseases that have a few important things in common. Cancer cells are abnormal and are divided without control or order. These cells can invade and destroy the tissue found around them. Cancer cells can break away from a malignant tumor and enter the bloodstream or lymphatic system. This process, called metastasis, is the way by which cancer spreads from the original tumor to form new tumors in different parts of the body. The names of the most common cancers include carcinoma, sarcoma, lymphoma and leukemia.

Is it possible for a Pathologist to find abnormalities in my DNA?

There are some tests that help locate abnormalities in the DNA. However many studies and additional testing must be performed to clarify what these abnormalities mean.

The genetic pathology is an emerging area. Using molecular genetics techniques we can identify specific mutations associated especially with some tumors. We have immunohistochemistry, in situ hybridization and real time PCR.

What is the purpose of identifying these mutations?

To decide whether certain drugs will be useful to treat the tumor the person has.

LOCATION: Basement, next to the bank.

Working Hours: Monday to Friday from 7:00 am to 7:00 pm, Saturday from 9:00 am to 1:00 pm.

TELEPHONE: (appointments) 226 1520 / 399 8000, Ext. 2045