What is Kidney Cancer?
The kidney’s job is to filter the blood. This means that certain toxins or excessive amounts of products in the blood are eliminated through the urine.
This organ comprises different types of cells that grow, multiply and die in a continual process of cellular renewal.
When this cycle of renewal changes and abnormal cells are produced or are not destroyed at the right time, tumours form.
The occurrence of these situations has increased considerably over the last 25–30 years (around 2% per year) partly due to increased diagnosis of small lesions via imaging scans.
Kidney Cancer Risk Factors
High blood pressure
Diets rich in red meat
Other causes associated with kidney tumours appear to be renal replacement treatments and occupational exposure to products like asbestos, hydrocarbons (oil derivatives), heavy metals and even ionising radiation.
Hereditary diseases, such as Von Hippel-Lindau, may also increase the risk of cancer.
Types of Tumour
There are two types of kidney cancer:
- Renal cell carcinoma (RCC), which are tumours in the renal tissue and the most prevalent type (around 90% of malignant tumours). They correspond to some 2–3% of all malignant neoplasms in adults and are responsible for 2% of mortality by malignant tumour. There are various histological sub-types.
- Upper epithelial tumours, i.e. tumours in the kidney’s urinary tract, composed by a different cell of the type lining the bladder and ureter – transitional cell carcinoma.
- Other benign and malignant tumours like oncocytomas, angiomyolipomas and adenomas (benign) or sarcomas, lymphomas and others such as leukaemic infiltration of the kidney or metastases of tumours in other organs.
Kidney Cancer Symptoms
Many renal neoplasms are currently diagnosed accidentally during routine ultrasounds or appointments for other reasons.
Sometimes, no warning signs exist and the tumours cause no symptoms for a long time, allowing them to grow and to become more invasive and aggressive.
In the past, most tumours presented the so-called classical symptoms triad of back pain, palpable mass and blood in the urine (haematuria). These signalled that the disease was at an advanced stage. Fortunately, this situation is somewhat different today.
The patient may have:
- Back pain – resulting from the growth of the tumour and distension of the kidney capsule;
- Haematuria – the most common isolated symptom due to the tumour reaching the excretory system;
- Presence of a palpable mass – a later sign indicative of advanced stage cancer.
Other symptoms, for example, are loss of appetite, intermittent fever and extreme tiredness.
The cancer can also manifest itself via paraneoplastic syndromes or symptoms due to systemic metastisation.
Kidney Cancer Diagnosis
Kidney cancer diagnosis is generally done with imaging scans such as ultrasound, which must be confirmed later with a CT scan.
Occasionally, in cases where images arouse doubts, it may be necessary to confirm the disease with a biopsy on the tumour, but that is not the rule. Retrieving a fragment provides information about the type of specific cell comprising the tumour.
Ultrasound is a safe non-invasive exam with a high detection rate for lesions of more than 15 mm.
A computed tomography (CT) scan is effective for staging and follow up. This is the most common complementary test when deciding diagnostic intervention and/or therapy.
An alternative to a CT scan is nuclear magnetic ressonance (NMR).
Do you have any of these kidney cancer symptoms?
Kidney Cancer Treatment
Treatment depends on the stage and performance status (i.e. general state) of the patient.
The current therapeutic options depend on the stage at which the tumour is detected.
At the localised stage, they may include partial or radical nephrectomy, with laparoscopy being the most common surgery performed today for this problem. In some cases, minimally invasive therapies can be performed, such as cryotherapy, radiofrequency therapy or radiology.
At more advanced stages, systemic therapy (chemotherapy or immunotherapy), radiotherapy or palliative therapies may be necessary.
Kidney Cancer Prognosis
Assessing prognostic factors has undergone a major evolution in recent years and now uses isolated parameters to combine various factors.
When establishing a carcinoma prognosis, factors such as age, sex, race and performance status are assessed as well as anatomical and histopathological factors.
The main characteristics of the latter two are:
- Assessment of the stage;
- Lesion size and extent;
- Number and location of possible metastases;
- Histological subtype of the tumour;
- Venous incursion;
- Tumour necrosis.
This research culminated in the creation of various integrated prognostic models, given the variability in clinical evolution of this neoplasm according to the different parameters.
Dr. José Santos Dias
Clinical Director of the Instituto da Próstata
- Bacherlor's Degree from the Faculty of Medicine at the University of Lisbon
- Specialist in Urology
- Fellow of the European Board of Urology
- Autor dos livros "Tudo o que sempre quis saber Sobre Próstata", "Urologia fundamental na Prática Clínica", "Urologia em 10 minutos","Casos Clínicos de Urologia" e "Protocolos de Urgência em Urologia"
FAQs about Kidney Cancer
Can you prevent kidney cancer?
What are the symptoms of kidney cancer?
What causes kidney cancer?
How is kidney cancer diagnosed?
What is the treatment for kidney cancer?
- DIAS, José Santos. Urologia Fundamental: na prática clínica. Lisboa: Lidel - Edições Técnicas, Lda, 2010.
- What is Kidney Cancer?- https://www.nm.org/conditions-and-care-areas/cancer-care/genitourinary-cancer-care/kidney-cancer
- Kidney Cancer - https://www.mayoclinic.org/diseases-conditions/kidney-cancer/symptoms-causes/syc-20352664