Epidemiological studies are required to determine risk factors. Aside from exposure to vinyl chloride or ionizing radiation, there are no known environmental factors associated with brain tumors. Mutations and deletions of so-called tumor suppressor genes, such as P53, are thought to be the cause of some forms of brain tumor. Inherited conditions, such as Von Hippel–Lindau disease, multiple endocrine neoplasia, and neurofibromatosis type 2 carry a high risk for the development of brain tumors. People with celiac disease have a slightly increased risk of developing brain tumors.

Although studies have not shown any link between cell phone or mobile phone radiation and the occurrence of brain tumors, the World Health Organization has classified mobile phone radiation on the IARC scale into Group 2B – possibly carcinogenic. Discounting claims that current cell phone usage may cause brain cancer, modern, third-generation (3G) phones emit, on average, about 1% of the energy emitted by the GSM (2G) phones that were in use when epidemiological studies that observed a slight increase in the risk for glioma – a malignant type of brain cancer – among heavy users of wireless and cordless telephones were conducted.

Brain, other CNS or intracranial tumors are the ninth most common cancer in the UK (around 10,600 people were diagnosed in 2013), and it is the eighth most common cause of cancer death (around 5,200 people died in 2012).

Papillary tumors of pineal region are extremely rare, constituting 0.4-1% of all central nervous system tumors. These tumors most commonly occur in adults with the mean age being 31.5. There have been cases reported for people between the ages 5 to 66 years. There is a slight predominance of females who have these tumors.

Because of the rarity of these tumors, there is still a lot of unknown information. There are many case studies that have been reported on patients who have been diagnosed with this specific type of tumor. Most of the above information comes from the findings resulting from case studies.

Since Papillary Tumors of the Pineal Region were first described in 2003, there have been seventy cases published in the English literature. Since there is such a small number of cases that have been reported, the treatment guidelines have not been established. A larger number of cases that contain a longer clinical follow-up are needed to optimize the management of patients with this rare disease.

Even though there is a general consensus on the morphology and the immunohistochemical characteristics that is required for the diagnosis, the histological grading criteria have yet to be fully defined and its biological behavior appears to be variable. This specific type of tumor appears to have a high potential for local recurrence with a high tumor bed recurrence rate during the five years after the initial surgery. This suggests the need for a tumor bed boost radiotherapy after surgical resection.

As stated above, the specific treatment guidelines have not yet been established, however, gross total resection of the tumor has been the only clinical factor associated overall and progression-free survival. The value of radiotherapy as well as chemotherapy on disease progression will need to be investigated in future trials. With this information, it will provide important insight into long-term management and may further our understanding of the histologic features of this tumor.

Factors that contribute to the development of hypopharyngeal cancer include:

- Smoking

- Chewing tobacco

- Heavy alcohol use

- Poor diet

Smoking, like lung cancer, can cause hypopharyngeal cancer because it contains carcinogens that alter the DNA or RNA in a dividing cell. These alterations may change a normal DNA sequence to an oncogene, a gene that causes cancer after exposure to a carcinogen.

Squamous cells, a type of cell that lines hollow organs like the throat, mouth, lungs, and outer layer of skin, are particularly vulnerable when exposed to cigarette smoke.

Chewing tobacco can have the same effects as smoking and is also linked to hypopharyngeal cancer. The chewing tobacco is placed into the mouth, leaving it exposed to enzymes, like amylase, which partly digests the carcinogenic material. Saliva is swallowed, along with the cancer-promoting material, which passes through the hypopharynx on its way to the esophagus.

Heavy alcohol use is linked to Hypopharyngeal Cancer as well. Alcohol damages the lining of the hypopharynx, increasing the amount of chemicals that are allowed to seep into the underlying membranes. Heavy alcohol use is also associated with nutritional deficiencies.

A disease called Plummer-Vinson syndrome, a genetic disorder that causes a long-term iron deficiency, may also lead to Hypopharyngeal Cancer. Other factors like a deficiency in certain vitamins also appear to contribute to this type of cancer.

Adult survivors of childhood cancer have some physical, psychological, and social difficulties.

Premature heart disease is a major long-term complication in adult survivors of childhood cancer. Adult survivors are eight times more likely to die of heart disease than other people, and more than half of children treated for cancer develop some type of cardiac abnormality, although this may be asymptomatic or too mild to qualify for a clinical diagnosis of heart disease.

Children with cancer are at risk for developing various cognitive or learning problems. These difficulties may be related to brain injury stemming from the cancer itself, such as a brain tumor or central nervous system metastasis or from side effects of cancer treatments such as chemotherapy and radiation therapy. Studies have shown that chemo and radiation therapies may damage brain white matter and disrupt brain activity.

Prognosis and treatment is the same as for the most common type of ovarian cancer, which is epithelial ovarian cancer.

The median survival of primary peritoneal carcinomas is usually shorter by 2–6 months time when compared with serous ovarian cancer. Studies show median survival varies between 11.3–17.8 months. One study reported 19-40 month median survival (95% CI) with a 5-year survival of 26.5%.

Elevated albumin levels have been associated with a more favorable prognosis.

A urogenital neoplasm is a tumor of the urogenital system.

Types include:

- Cancer of the breast and female genital organs: (Breast cancer, Vulvar cancer, Vaginal cancer, Cervical cancer, Uterine cancer, Endometrial cancer, Ovarian cancer)

- Cancer of the male genital organs (Carcinoma of the penis, Prostate cancer, Testicular cancer)

- Cancer of the urinary organs (Renal cell carcinoma, Bladder cancer)

People with HPV-mediated oropharyngeal cancer tend to have higher survival rates. The prognosis for people with oropharyngeal cancer depends on the age and health of the person and the stage of the disease. It is important for people with oropharyngeal cancer to have follow-up exams for the rest of their lives, as cancer can occur in nearby areas. In addition, it is important to eliminate risk factors such as smoking and drinking alcohol, which increase the risk for second cancers.

Invasive carcinoma of no special type (NST) also known as invasive ductal carcinoma or ductal NOS and previously known as invasive ductal carcinoma, not otherwise specified (NOS) is a group of breast cancers that do not have the "specific differentiating features". Those that have these features belong to other types.

In this group are: pleomorphic carcinoma, carcinoma with osteoclast-like stromal giant cells, carcinoma with choriocarcinomatous features, and carcinoma with melanotic features. It is a diagnosis of exclusion, which means that for the diagnosis to be made all the other specific types must be ruled out.

It occurs in all adult age groups. While the majority of patients are between 40 and 59 years old, age predilection is much less pronounced than in noninflammatory breast cancer. The overall rate is 1.3 cases per 100000, black women (1.6) have the highest rate, Asian and Pacific Islander women the lowest (0.7) rates.

Most known breast cancer risk predictors do not apply for inflammatory breast cancer. It may be slightly associated with cumulative breast-feeding duration.

Smoking tobacco appears to increase the risk of breast cancer, with the greater the amount smoked and the earlier in life that smoking began, the higher the risk. In those who are long-term smokers, the risk is increased 35% to 50%. A lack of physical activity has been linked to about 10% of cases. Sitting regularly for prolonged periods is associated with higher mortality from breast cancer. The risk is not negated by regular exercise, though it is lowered.

There is an association between use of hormonal birth control and the development of premenopausal breast cancer, but whether oral contraceptives use may actually cause premenopausal breast cancer is a matter of debate. If there is indeed a link, the absolute effect is small. Additionally, it is not clear if the association exists with newer hormonal birth controls. In those with mutations in the breast cancer susceptibility genes "BRCA1" or "BRCA2", or who have a family history of breast cancer, use of modern oral contraceptives does not appear to affect the risk of breast cancer.

The association between breast feeding and breast cancer has not been clearly determined; some studies have found support for an association while others have not. In the 1980s, the abortion–breast cancer hypothesis posited that induced abortion increased the risk of developing breast cancer. This hypothesis was the subject of extensive scientific inquiry, which concluded that neither miscarriages nor abortions are associated with a heightened risk for breast cancer.

A number of dietary factors have been linked to the risk for breast cancer. Dietary factors which may increase risk include a high fat diet, high alcohol intake, and obesity-related high cholesterol levels. Dietary iodine deficiency may also play a role. Evidence for fiber is unclear. A 2015 review found that studies trying to link fiber intake with breast cancer produced mixed results. In 2016 a tentative association between low fiber intake during adolescence and breast cancer was observed.

Other risk factors include radiation and shift-work. A number of chemicals have also been linked, including polychlorinated biphenyls, polycyclic aromatic hydrocarbons, and organic solvents Although the radiation from mammography is a low dose, it is estimated that yearly screening from 40 to 80 years of age will cause approximately 225 cases of fatal breast cancer per million women screened.

CUP sometimes runs in families. It has been associated with familial lung, kidney, and colorectal cancers, which suggests that these sites may often be the origin of unidentifiable CUP cancers.

Use of the kangri pot has been correlated with the risk of Kangri cancer. The pot holds hot wood and charcoal, and as a unit, the pot is put in direct contact with the skin of the abdomen and the thigh areas as a way to keep warm during winters in north India. Elements that are believed to contribute to the development of Kangri cancer are heat, burning wood particles, smoke, soot, and tar of burnt chinar leaves that could also be used as a fuel source for burning in the production of heat.

In one study, researchers noted kangri pot usage patterns and found that Kangri cancer “patients gave the history of using the Kangri especially for 3-4 winter months [...] every year for 5-6 hours daily.”

Symptoms of Hypopharyngeal Cancer include:

- Swollen lymph nodes in the neck (first sign of a problem in half of all patients)

- Sore throat in one location that persists after treatment

- Pain that radiates from the throat to the ears

- Difficult or painful swallowing (often leads to malnutrition and weight loss because of a refusal to eat)

- Voice changes (late stage cancer)

Beyond the behavioral risk factor of prolonged usage of Kangri pots, researchers have begun to look at genetic mutations that may make some people more predisposed to develop Kangri cancer.

- In one study, compared to a control group, people with Kangri cancer were found to be approximately twice as likely to have a mutation in the TP53 gene (codon 72 polymorphism). Patients with higher grade tumors exhibited more proline amino acid mutations at this site.

- Another study confirmed this association of Kangri Cancer and TP53 mutations, specifically substitutions and insertions, in 40% of the Kangri cancer patients who were studied. The researchers observed a significant correlation with mutation status and age as well as with the presence of lymph nodes in patients. TP53 may, in the future, serve as “potential molecular marker and prognostic tool” for Kangri cancer. Furthermore, PTEN mutations were found in two of thirty patients studied; though due to the small sample size, no useful conclusions could be postulated.

- Two polymorphisms of the HSP70 gene were discovered to be correlated with “poor prognosis” of Kangri cancer; the “Hsp70-2 A/G or G/G and Hsp70homC/C genotypes” could potentially be utilized to measure risk of Kangri cancer development as well as to predict prognosis.

The risk factors that can increase the risk of developing oropharyngeal cancer are:

- Smoking and chewing tobacco

- Heavy alcohol use

- A diet low in fruits and vegetables

- Chewing betel quid, a stimulant commonly used in parts of Asia

- Mucosal infection with human papilloma virus (HPV) (HPV-mediated oropharyngeal cancer)

- HPV infection

- Plummer-Vinson syndrome

- Poor nutrition

- Asbestos exposure

Certain genetic changes including: P53 mutation and CDKN2A (p16) mutations.

High-risk lesions:

- Erythroplakia

- Speckled erythroplakia

- Chronic hyperplastic candidiasis

Medium-risk lesions:

- Oral submucosal fibrosis

- Syphilitic glossitis

- Sideropenic dysphagia (or Paterson-Kelly-Brown syndrome)

Low-risk lesions:

- Oral lichen planus

- Discoid lupus erythematosus

- Discoid keratosis congenita

Most people with cancer of unknown primary origin have widely disseminated and incurable disease, although a few can be cured through treatment. With treatment, typical survival with CUP ranges from 6 to 16 months. Survival rates are lower in cases with visceral metastatic disease, ranging from 6 to 9 months. Survival rates are higher when the cancer is more limited to lymph nodes, pleura, or peritoneal metastasis, which ranges from 14 to 16 months. Long-term prognosis is somewhat better if a particular source of cancer is strongly suggested by clinical evidence.

Some studies in Australia, Brazil and Germany pointed to alcohol-containing mouthwashes as also being potential causes. The claim was that constant exposure to these alcohol-containing rinses, even in the absence of smoking and drinking, leads to significant increases in the development of oral cancer. However, studies conducted in 1985, 1995, and 2003 summarize that alcohol-containing mouth rinses are not associated with oral cancer. In a March 2009 brief, the American Dental Association said "the available evidence does not support a connection between oral cancer and alcohol-containing mouthrinse". A 2008 study suggests that acetaldehyde (a breakdown product of alcohol) is implicated in oral cancer, but this study specifically focused on abusers of alcohol and made no reference to mouthwash. Any connection between oral cancer and mouthwash is tenuous without further investigation.

In a study of Europeans, smoking and other tobacco use was associated with about 75 percent of oral cancer cases, caused by irritation of the mucous membranes of the mouth from smoke and heat of cigarettes, cigars, and pipes. Tobacco contains over 60 known carcinogens, and the combustion of it, and by-products from this process, is the primary mode of involvement. Use of chewing tobacco or snuff causes irritation from direct contact with the mucous membranes.

Tobacco use in any form by itself, and even more so in combination with heavy alcohol consumption, continues to be an important risk factor for oral cancer. However, due to the current trends in the spread of HPV16, as of early 2011 the virus is now considered the primary causative factor in 63% of newly diagnosed patients.

Although the precise causes are not known, a link with certain variants of BRCA1/2 has been described. Furthermore, women with BRCA1/2 mutation have a 5% risk of developing primary peritoneal cancer even after prophylactic oophorectomy.

Primary peritoneal carcinoma shows similar rates of tumor suppressor gene dysfunction (p53, BRCA, WT1) as ovarian cancer and can also show an increased expression of HER-2/neu.

An association with vascular endothelial growth factor has been observed.

Alcohol consumption does not appear to be related to ovarian cancer. Other factors that have been investigated, such as smoking, low levels of vitamin D in the blood, presence of inclusion ovarian cysts, and infection with human papilloma virus (the cause of some cases of cervical cancer), have been disproven as risk factors for ovarian cancer. The carcinogenicity of perineal talc is controversial, because it can act as an irritant if it travels through the reproductive tract to the ovaries. Case-control studies have shown that use of perineal talc does increase the risk of ovarian cancer, but using talc more often does not create a greater risk. Use of talc elsewhere on the body is unrelated to ovarian cancer. Sitting regularly for prolonged periods is associated with higher mortality from epithelial ovarian cancer. The risk is not negated by regular exercise, though it is lowered.

Increased age (up to the 70s) is a risk factor for epithelial ovarian cancer because more mutations in cells can accumulate and eventually cause cancer. Those over 80 are at slightly lower risk.

Smoking tobacco is associated with a higher risk of mucinous ovarian cancer; after smoking cessation, the risk eventually returns to normal.A diet high in animal fats may be associated with ovarian cancer, but the connection is unclear. Diet seems to play a very small role, if any, in ovarian cancer risk.

Higher levels of C-reactive protein are associated with a higher risk of developing ovarian cancer.

Industrialized nations, with the exception of Japan, have high rates of epithelial ovarian cancer, which may be due to diet in those countries. Caucasian are at a 30–40% higher risk for ovarian cancer when compared to Black and Hispanic people, likely due to socioeconomic factors; white women tend to have fewer children and different rates of gynecologic surgeries that affect risk for ovarian cancer.

Cohort studies have found a correlation between dairy consumption and ovarian cancer, but case-control studies do not show this correlation. There is mixed evidence regarding the effect of red meat and processed meat in ovarian cancer.

Tentative evidence suggests that talc, pesticides, and herbicides increase the risk of ovarian cancer. The American Cancer Society notes that as of now, no study has been able to accurately link any single chemical in the environment, or in the human diet, directly to mutations that cause ovarian cancer.

According to the NIH Consensus Conference , if DCIS is allowed to go untreated, the natural course or natural history varies according to the grade of the DCIS. Unless treated, approximately 60 percent of low-grade DCIS lesions will have become invasive at 40 years follow-up. High-grade DCIS lesions that have been inadequately resected and not given radiotherapy have a 50 percent risk of becoming invasive breast cancer within seven years. Approximately half of low-grade DCIS detected at screening will represent overdiagnosis, but overdiagnosis of high-grade DCIS is rare. The natural history of intermediate-grade DCIS is difficult to predict. Approximately one-third of malignant calcification clusters detected at screening mammography already have an invasive focus.

The prognosis of IDC depends, in part, on its histological subtype. Mucinous, papillary, cribriform, and tubular carcinomas have longer survival, and lower recurrence rates. The prognosis of the most common form of IDC, called "IDC Not Otherwise Specified", is intermediate. Finally, some rare forms of breast cancer (e.g., sarcomatoid carcinoma, inflammatory carcinoma) have a poor prognosis. Regardless of the histological subtype, the prognosis of IDC depends also on tumor size, presence of cancer in the lymph nodes, histological grade, presence of cancer in small vessels (vascular invasion), expression of hormone receptors and of oncogenes like HER2/neu.

These parameters can be entered into models that provide a statistical probability of systemic spread. The probability of systemic spread is a key factor in determining whether radiation and chemotherapy are worthwhile. The individual parameters are important also because they can predict how well a cancer will respond to specific chemotherapy agents.

Overall, the 5-year survival rate of invasive ductal carcinoma was approximately 85% in 2003.