Cancer seeds were sown many years before the symptoms manifest: genetic study reveals

The research could lead to possibility of understanding the diagnosis of cancer and its cure

By Parvathy Rajagopal
Updated February 8, 2020 20:12 +08

Cancer | One of the most common disease in the world

Early signs of cancer can appear years or even decades before the actual diagnosis of cancer in the body. A genetic study has revealed that there is a long window of opportunity to diagnose cancer in certain cancer types.

The study was carried out as part of the Pan-Cancer Analysis of Whole Genomes project. It is said to be one of the most comprehensive studies of cancer genetics to date. Although the findings might not change the diagnosis of cancer in patients in the immediate future, the study believes that the risk can be assessed far earlier than expected.

One of the co-authors of the research, Peter Van Loo, from the Francis Crick Institute in London, told a news channel that unlocking the patterns can help in developing new diagnostic tests and pick up any sign of cancer at a very early stage.

Scientists analyzed several samples

The findings are based on a sample of 2,500 tumors and 38 cancer types. According to the study, the earliest mutations happened in only nine genes. This means that the pool of genes that is common that can reveal the triggers for cells to diverge from healthy development to a path towards cancer is relatively small. The study says that this revelation can increase the possibility of detection of the mutation of the cancer cells through liquid biopsies.

The study has opened a window for wider research possibilities which could help in the detection and curing of cancer in humans. Although the human cells go through billions of mutations, only a small number of them called the driver mutations can cause cancer.

The analysis of the research was published in Nature as part of the pan-cancer project and involved 22 other papers.

Common symptoms related to common cancers

The study has changed the perspective in the diagnosis of cancer since the symptoms relating to cancer can take time to be visible in the body. According to the World Health Organization, it is the second leading cause of death globally. The most common cancers and their symptoms are:

Lung Cancer- It can cause shortness of breath, and loss of weight even without trying. A new cough that won't go away, coughing up blood, chest pain, hoarseness, chest pain, bone pain, and headache are said to be a few of the common symptoms of lung cancer. One of the major reasons for cancer is smoking which can be direct or secondhand smoke. It can be caused due to other reasons as well.
Breast Cancer- The symptoms can be different in different people. But, the common symptoms that can be taken as early warning signs are skin changes that can mean change in color or swelling in one or both the breasts, increase in the size or change in the shape of the breast, changes in the nipples, nipple discharge other than breast milk, general pain and lumps in the breasts. More specific symptoms include itchy breasts, change in breast color, changes in touch, flaking of the nipple skin, breast lump or thickening and redness or the pitting of the breasts.
Colorectal Cancer- The early warning signs of colorectal cancer are that there will be rectal bleeding, narrow stools, tenesmus, anemia, persistent pain in the abdomen and unexplained weight loss. The local symptoms surrounding the colon or rectum where it has not spread to other organs include constipation, diarrhea, or alternating between the two, changes in the bowel habits, blood in the stool or rectal bleeding, abdominal pain or cramps, feeling that the bowel isn't empty completely, and stools that are thinner than normal. If colorectal cancer has spread to other organs such as the digestive tract then the symptoms could be unexplained loss of appetite, weight loss, jaundice, nausea, anemia, weakness, and fatigue.
Prostate Cancer- The symptoms can include trouble urinating, blood in semen, decreased force in the stream of urine, discomfort in the pelvic region, erectile dysfunction and bone pain.
Skin Cancer- There are different types of skin cancers. Types of skin cancers include Basal cell carcinoma, Nonmelanoma skin cancer, Melanoma skin cancer and Squamous cell carcinoma of the skin. Basal cell carcinoma is the most common type of skin cancer and can appear as a pearly wax or a bump, flat, flesh-colored or brown scar-like lesion, bleeding or scabbing sore that heals and returns. Melanoma has symptoms which include large brownish spot with darker speckles, a mole that changes shape or size or color or that bleeds, a small wound with an irregular border and portions that appear in different colors, a painful wound that itches or burns, and a dark wound on your palms, soles, fingertips or toes, or on mucous membranes lining your mouth, nose, vagina or anus. Squamous cell carcinoma appears as a firm red nodule or as a flat wound with a scaly surface. There are other less common types of skin cancer as well.
Stomach Cancer- The symptoms include fatigue, feeling bloated after eating, feeling full after eating small portions of food, severe and persistent heartburn, indigestion, nausea, stomach pain, vomiting, and unintentional weight loss.