Cancer diagnosis: Understanding the doctor’s letter

 When you were diagnosed with cancer, it was certainly a big shock, as it is for many patients. Often you don't know how to deal with the disease or what it means for you. A detailed examination of the diagnosis and the test results can help you to understand your own disease better.

An important clue is the so-called doctor's letter. We would like to help you clarify important questions regarding doctor’s letters and findings.

Diagnoses and abbreviations explained, Structure of a doctor’s letter

• In addition to the address details of the treating physicians, the doctor's letter contains important information about the patient's personal data and his or her treatment.
• If it is an inpatient hospital stay, the date, place of admission and length of stay are stated; if the patient is referred to another specialist, the date of treatment is stated.
• It all starts with a medical diagnosis. A diagnosis does not just consist of the name of the disease. It also includes the diagnostic tests that are carried out on the patient and which ultimately lead to the diagnosis, the name of the disease.
• This also includes the physical findings, which represent the results of the direct examination of the patient (e.g. auscultation).
• Laboratory values can be used to determine whether certain body fluids (e.g. blood or urine) have high or low values by comparing them with average values. For example, some tumors produce increased amounts of proteins or protein-containing substances. Substances that can indicate the presence and stage or malignancy of a tumor in the body are therefore often referred to as "tumor markers".

A "positive" result means that the doctors found something unusual during the examination. A "negative" result means that an examination does not reveal anything unusual.

 

A finding is the result of an examination, i.e. what doctors have "discovered". A distinction is made between "positive" and "negative" findings: A "positive" finding means that the doctors found something unusual during the examination. A "negative" finding is when an examination does not reveal any abnormalities.

The pathological findings represent the results of the examination of tissue samples for pathological changes. This is the only way to ensure a cancer diagnosis. Using certain properties of tumors, predictions can be made about the expected course of the disease.

Instrumental diagnostics refer to examinations that are carried out using technical equipment. In addition to imaging procedures such as X-rays, computer tomography (CT) or magnetic resonance imaging (MRI), these also include colonoscopy and examination of the heart using an electrocardiograph (ECG).

After the diagnosis, the doctor's letter contains the medical anamnesis (Latin for "memory"), which lists the course of therapy chronologically to provide an overview of previous treatments. In the case of cancer, this can include the status of the therapy method used as well as information on the spread of the disease in the body.

The last and perhaps most important part of the doctor's letter is the epicrisis (Greek for "assessment"). This refers to the summary and professional interpretation of the treatments and findings. The key findings that led to the diagnosis are then summarized and evaluated in a logical and understandable manner. From this, prognoses for the course of the disease as well as recommendations for therapy and medication are derived.

Attached to the doctor's letter are detailed findings that provide a summary of all medical examinations carried out. The appendix contains a detailed description of the medical history, the physical examination results, the imaging findings and, if applicable, the results of other examinations carried out.

Diagnostic code and classification, ICD and TNM

In order to classify cancer more precisely, doctors use so-called ICD codes (International Classification of Diseases, ICD-10-GM). All letters and numbers from 0 to 99 are used to describe diseases. For example, C34 stands for lung cancer, C50 for breast cancer, etc.

Other numbers indicate the exact location of the tumor in the affected organ: C34.1, for example, stands for a tumor in the upper part of the lung.

In order to provide even more precise information on the spread of cancer, the TNM system is usually used.

 

This is a code of numbers and letters that describes the spread of cancer in the body. This system takes into account the following assessment of the tumor:

• T (tumor) = tumor size and local extent
• N (Nodus) = Lymph node involvement
• M (metastases) = spread of other tumors in the body

The numbers after the letters stand for:

• T1-T4= size and extent of the (primary) tumor TX – no assessment possible, T0 – no evidence of primary tumor (e.g. if the primary tumor is unknown and only metastases are found), Tis – carcinoma in situ (lat. "cancer at the site of origin"), T1 – <2cm up to T4 – any tumor size
• N0-N3= number and location of affected lymph nodes in the region of the tumor NX – no assessment possible, N0 – no lymph node metastases, N1 up to N3 – lymph node involvement of regional lymph nodes increasingly further away from the tumor
• M0 or M1 = presence or absence of distant metastases. If necessary, the location of the metastasis can be indicated. There are corresponding abbreviations for this: e.g. PUL = lung, OSS = bone, HEP = liver, BRA = brain, etc.

An example: T1 N0 M0 means a small tumor without lymph node involvement and metastases. For some tumors, the experts make even more precise classifications. The T numbers are then supplemented with the lowercase letters a to d.

This additional information allows even more precise statements to be made about the size and local spread of the primary tumor (T). The letters are defined differently depending on the type of tumor.

Additional abbreviations

• R: Tumor residues in the body after surgery (R0-R2)
• C: Reliability (Certainty) of the test results (C1-C5)
• X: Feature cannot yet be assessed (not yet examined or the result is not clear)
• r: "Recurrence" or "relapse", that is: the cancer has returned
• y: "multimodality", i.e. a multifaceted treatment (complementary treatments such as radiotherapy in addition to the therapy used)

Trailing lowercase letters

• m: Describes whether several tumors were found in one and the same organ. Sometimes you will also find the number of tumors in brackets after the T number.
• cy (=cytological): To determine whether a tumor has possibly spread in the body, the chest or abdominal cavity can be rinsed before or during an operation. If cancer cells are detectable in the rinsing fluid, the tumor has spread in the body.

To indicate how advanced the disease is, the so-called "staging" is used.

 

This is important for therapy planning, as it provides information about the possible course of the disease. The International Federation Against Cancer has defined four stages for most tumor diseases. For some types of cancer, there are further subdivisions, which are indicated with an additional lowercase letter (eg IIa or IVb).

The "grading" indicates on a three to five-stage scale (G0-G4) to what extent the tumor tissue differs from normal tissue, ie how malignant a tumor is. The less the tumor tissue differs from the original healthy tissue, the better the prognosis.

However, for some types of tumors, these classifications are not useful because the prognosis of the cancer does not depend solely on the size or spread of the tumor, but is also determined by other factors. For example, other classification systems are used for leukemia, skin cancer, brain tumors and gynecological tumors. You can find more information about the classifications used here at Office of Cancer Centers.

Please note that the information in this blog post is intended to provide an overview of the most common terms. It is not intended to be exhaustive. For further information, it is important to consult a doctor.