Anal Pap smears similar to those used in cervical cancer screening have been studied for early detection of anal cancer in high-risk individuals. In 2011, the HIV clinic implemented a program to enhance access to anal cancer screening for HIV-positive men. Nurse practitioners perform anal Papanicolaou screening, and men with abnormal results receive further evaluation with high-resolution anoscopy. The program has helped identify many precancerous growths, allowing them to be safely removed.

Since many, if not most, anal cancers derive from HPV infections, and since the HPV vaccine before exposure to HPV prevents infection by some strains of the virus and has been shown to reduce the incidence of potentially precancerous lesions, scientists surmise that HPV vaccination may reduce the incidence of anal cancer.

On 22 December 2010, the U.S. Food and Drug Administration approved Gardasil vaccine to prevent anal cancer and pre-cancerous lesions in males and females aged 9 to 26 years. The vaccine has been used before to help prevent cervical, vulvar, and vaginal cancer, and associated lesions caused by HPV types 6, 11, 16, and 18 in women.

People with Barrett's esophagus (a change in the cells lining the lower esophagus) are at much higher risk, and may receive regular endoscopic screening for the early signs of cancer. Because the benefit of screening for adenocarcinoma in people without symptoms is unclear, it is not recommended in the United States. Some areas of the world with high rates of squamous-carcinoma have screening programs.

Staging is based on the TNM staging system, which classifies the amount of tumor invasion (T), involvement of lymph nodes (N), and distant metastasis (M). The currently preferred classification is the 2010 AJCC staging system for cancer of the esophagus and the esophagogastric junction. To help guide clinical decision making, this system also incorporates information on cell type (ESCC, EAC, etc.), grade (degree of differentiation – an indication of the biological aggressiveness of the cancer cells), and tumor location (upper, middle, lower, or junctional).

Checking the cervix by the Papanicolaou test, or Pap test, for cervical cancer has been credited with dramatically reducing the number of cases of and mortality from cervical cancer in developed countries. Pap test screening every three to five years with appropriate follow-up can reduce cervical cancer incidence up to 80%. Abnormal results may suggest the presence of precancerous changes, allowing examination and possible preventive treatment. The treatment of low-grade lesions may adversely affect subsequent fertility and pregnancy. Personal invitations encouraging women to get screened are effective at increasing the likelihood they will do so. Educational materials also help increase the likelihood women will go for screening, but they are not as effective as invitations.

According to the 2010 European guidelines, the age at which to start screening ranges between 20 and 30 years of age, but preferentially not before age 25 or 30 years, and depends on burden of the disease in the population and the available resources.

In the United States, screening is recommended to begin at age 21, regardless of age at which a woman began having sex or other risk factors. Pap tests should be done every three years between the ages of 21 and 65. In women over the age of 65, screening may be discontinued if no abnormal screening results were seen within the previous 10 years and no history of CIN 2 or higher exists. HPV vaccination status does not change screening rates. Screening can occur every 5 years between ages 30 and 65 when a combination of cervical cytology screening and HPV testing is used and this is preferred. However, it is acceptable to screen this age group with a Pap test alone every three years. Screening is not beneficial before age 25 as the rate of disease is low. Screening is not beneficial in women older than 60 years if they have a history of negative results. The American Society of Clinical Oncology (ASCO) guideline has recommend for different levels of resource availability.

Liquid-based cytology is another potential screening method. Although it was probably intended to improve on the accuracy of the Pap test, its main advantage has been to reduce the number of inadequate smears from around 9% to around 1%. This reduces the need to recall women for a further smear. The United States Preventive Services Task Force supports screening every 5 years in those who are between 30 and 65 years when cytology is used in combination with HPV testing.

Pap tests have not been as effective in developing countries. This is in part because many of these countries have an impoverished health care infrastructure, too few trained and skilled professionals to obtain and interepret Pap tests, uninformed women who get lost to follow-up, and a lengthy turn-around time to get results. These realities have resulted in the investigation of cervical screening approaches that use fewer resources and offer rapid results such as visual inspection with acetic acid or HPV DNA testing.

Diagnosis is made by the doctor on the basis of a medical history, physical examination, and special investigations which may include a chest x-ray, CT or MRI scans, and tissue biopsy. The examination of the larynx requires some expertise, which may require specialist referral.

The physical exam includes a systematic examination of the whole patient to assess general health and to look for signs of associated conditions and metastatic disease. The neck and supraclavicular fossa are palpated to feel for cervical adenopathy, other masses, and laryngeal crepitus. The oral cavity and oropharynx are examined under direct vision. The larynx may be examined by indirect laryngoscopy using a small angled mirror with a long handle (akin to a dentist's mirror) and a strong light. Indirect laryngoscopy can be highly effective, but requires skill and practice for consistent results. For this reason, many specialist clinics now use fibre-optic nasal endoscopy where a thin and flexible endoscope, inserted through the nostril, is used to clearly visualise the entire pharynx and larynx. Nasal endoscopy is a quick and easy procedure performed in clinic. Local anaesthetic spray may be used.

If there is a suspicion of cancer, biopsy is performed, usually under general anaesthetic. This provides histological proof of cancer type and grade. If the lesion appears to be small and well localised, the surgeon may undertake excision biopsy, where an attempt is made to completely remove the tumour at the time of first biopsy. In this situation, the pathologist will not only be able to confirm the diagnosis, but can also comment on the completeness of excision, i.e., whether the tumour has been completely removed. A full endoscopic examination of the larynx, trachea, and esophagus is often performed at the time of biopsy.

For small glottic tumours further imaging may be unnecessary. In most cases, tumour staging is completed by scanning the head and neck region to assess the local extent of the tumour and any pathologically enlarged cervical lymph nodes.

The final management plan will depend on the site, stage (tumour size, nodal spread, distant metastasis), and histological type. The overall health and wishes of the patient must also be taken into account. A prognostic multigene classifier has been shown to be potentially useful for the distinction of laryngeal cancer of low or high risk of recurrence and might influence the treatment choice in future.

The US Preventive Services Task Force (USPSTF) in 2013 stated evidence was insufficient to determine the balance of benefits and harms of screening for oral cancer in adults without symptoms by primary care providers. The American Academy of Family Physicians comes to similar conclusions while the American Cancer Society recommends that adults over 20 years who have periodic health examinations should have the oral cavity examined for cancer. The American Dental Association recommends that providers remain alert for signs of cancer during routine examinations.

There are a variety of screening devices, however, there is no evidence that routine use of these devices in general dental practice is helpful. However, there are compelling reasons to be concerned about the risk of harm this device may cause if routinely used in general practice. Such harms include false positives, unnecessary surgical biopsies and a financial burden on the patient.

After the initial diagnosis of Barrett's esophagus is rendered, affected persons undergo annual surveillance to detect changes that indicate higher risk to progression to cancer: development of epithelial dysplasia (or "intraepithelial neoplasia").

Considerable variability is seen in assessment for dysplasia among pathologists. Recently, gastroenterology and GI pathology societies have recommended that any diagnosis of high-grade dysplasia in Barrett be confirmed by at least two fellowship-trained GI pathologists prior to definitive treatment for patients. For more accuracy and reproductibility, it is also recommended to follow international classification system as the "Vienna classification" of gastrointestinal epithelial neoplasia (2000).

Early diagnosis of oral cancer patients would decrease mortality and help to improve treatment. Oral surgeons and dentists can diagnose these patients in the early stages. Health providers, dentists, and oral surgeons shall have high knowledge and awareness that would help them to provide better diagnosis for oral cancer patients. An examination of the mouth by the health care provider, dentist, oral surgeons shows a visible and/or palpable (can be felt) lesion of the lip, tongue, or other mouth area. The lateral/ventral sides of the tongue are the most common sites for intraoral SCC. As the tumor enlarges, it may become an ulcer and bleed. Speech/talking difficulties, chewing problems, or swallowing difficulties may develop. A feeding tube is often necessary to maintain adequate nutrition. This can sometimes become permanent as eating difficulties can include the inability to swallow even a sip of water. The doctor can order some special investigations which may include a chest x-ray, CT or MRI scans, and tissue biopsy.

While a dentist, physician or other health professional may suspect a particular lesion is malignant, there is no way to tell by looking alone - since benign and malignant lesions may look identical to the eye. A non-invasive brush biopsy (BrushTest) can be performed to rule out the presence of dysplasia (pre-cancer) and cancer on areas of the mouth that exhibit an unexplained color variation or lesion. The only definitive method for determining if cancerous or precancerous cells are present is through biopsy and microscopic evaluation of the cells in the removed sample. A tissue biopsy, whether of the tongue or other oral tissues and microscopic examination of the lesion confirm the diagnosis of oral cancer or precancer.

Avoidance of recognised risk factors (as described above) is the single most effective form of prevention. Regular dental examinations may identify pre-cancerous lesions in the oral cavity.

When diagnosed early, oral, head and neck cancers can be treated more easily and the chances of survival increase tremendously. As of 2017 it was not known if existing HPV vaccines can help prevent head and neck cancer.

The U.S. Preventive Services Task Force (USPSTF) issues recommendations for various cancers:

- Strongly recommends cervical cancer screening in women who are sexually active and have a cervix at least until the age of 65.

- Recommend that Americans be screened for colorectal cancer via fecal occult blood testing, sigmoidoscopy, or colonoscopy starting at age 50 until age 75.

- Evidence is insufficient to recommend for or against screening for skin cancer, oral cancer, lung cancer, or prostate cancer in men under 75.

- Routine screening is not recommended for bladder cancer, testicular cancer, ovarian cancer, pancreatic cancer, or prostate cancer.

- Recommends mammography for breast cancer screening every two years from ages 50–74, but does not recommend either breast self-examination or clinical breast examination. A 2013 Cochrane review concluded that breast cancer screening by mammography had no effect in reducing mortality because of overdiagnosis and overtreatment.

The presence of goblet cells, called intestinal metaplasia, is necessary to make a diagnosis of Barrett's esophagus. This frequently occurs in the presence of other metaplastic columnar cells, but only the presence of goblet cells is diagnostic. The metaplasia is grossly visible through a gastroscope, but biopsy specimens must be examined under a microscope to determine whether cells are gastric or colonic in nature. Colonic metaplasia is usually identified by finding goblet cells in the epithelium and is necessary for the true diagnosis.

Many histologic mimics of Barrett's esophagus are known (i.e. goblet cells occurring in the transitional epithelium of normal esophageal submucosal gland ducts, "pseudogoblet cells" in which abundant foveolar [gastric] type mucin simulates the acid mucin true goblet cells). Assessment of relationship to submucosal glands and transitional-type epithelium with examination of multiple levels through the tissue may allow the pathologist to reliably distinguish between goblet cells of submucosal gland ducts and true Barrett's esophagus (specialized columnar metaplasia). Use of the histochemical stain Alcian blue pH 2.5 is also frequently used to distinguish true intestinal-type mucins from their histologic mimics. Recently, immunohistochemical analysis with antibodies to CDX-2 (specific for mid and hindgut intestinal derivation) has also been used to identify true intestinal-type metaplastic cells. The protein AGR2 is elevated in Barrett's esophagus and can be used as a biomarker for distinguishing Barrett epithelium from normal esophageal epithelium.

The presence of intestinal metaplasia in Barrett's esophagus represents a marker for the progression of metaplasia towards dysplasia and eventually adenocarcinoma. This factor combined with two different immunohistochemical expression of p53, Her2 and p16 leads to two different genetic pathways that likely progress to dysplasia in Barrett's esophagus.

Cervical cancer is staged by the International Federation of Gynecology and Obstetrics (FIGO) staging system, which is based on clinical examination, rather than surgical findings. It allows only these diagnostic tests to be used in determining the stage: palpation, inspection, colposcopy, endocervical curettage, hysteroscopy, cystoscopy, proctoscopy, intravenous urography, and X-ray examination of the lungs and skeleton, and cervical conization.

An important anatomic landmark in anal cancer is the pectinate line (dentate line), which is located about 1–2 cm from the anal verge (where the anal mucosa of the anal canal becomes skin). Anal cancers located above this line (towards the head) are more likely to be carcinomas, whilst those located below (towards the feet) are more likely to be squamous cell carcinomas that may ulcerate. Anal cancer is strongly associated with ulcerative colitis and the sexually transmissible infections HPV and HIV. Anal cancer may be a cause of constipation or tenesmus, or may be felt as a palpable mass, although it may occasionally present as an ulcerative form.

Anal cancer is investigated by biopsy and may be treated by excision and radiotherapy, or with external beam radiotherapy and adjunctive chemotherapy. The five-year survival rate with the latter procedure is above 70%.

Screens for gastric cancer using photofluorography due to the high incidence there.

There are several ways to diagnose Hypopharyngeal Cancer.

- Physical Examination:

The doctor checks for swollen lymph nodes and may look down the patient’s throat with a long handled mirror.

- Endoscopy, Esophagoscopy, or Bronchoscopy:

Inserted into the nose or mouth of the patient, this a thin, lighted tube that allows the doctor to see farther down the throat, into the esophagus or into the trachea.

- Biopsy:

This is a small tissue sample that can be acquired during an endosopy, esophagoscopy, or bronchoscopy. The tissue is analyzed for the presences of cancer cells.

- CT scan or MRI:

These tests will give doctors a detailed picture of any abnormalities in the body. For a CT scan, the patient often swallows a dye that coats the throat and provides a better image. An MRI is a better tool if the patient is pregnant because the test uses no radiation.

Colorectal cancer is a disease of old age: It typically originates in the secretory cells lining the gut, and risk factors include diets low in vegetable fibre and high in fat. If a younger person gets such a cancer, it is often associated with hereditary syndromes like Peutz-Jegher's, hereditary nonpolyposis colorectal cancer or familial adenomatous polyposis. Colorectal cancer can be detected through the bleeding of a polyp, colicky bowel pain, a bowel obstruction or the biopsy of a polyp at a screening colonoscopy. A constant feeling of having to go to the toilet or anemia might also point to this kind of cancer.

Use of a colonoscope can find these cancers, and a biopsy can reveal the extent of the involvement of the bowel wall. Removal of a section of the colon is necessary for treatment, with or without chemotherapy. Colorectal cancer has a comparatively good prognosis when detected early.

Staging cancer is a way of marking the cancer’s progression and is measured on a 0 to 4 (IV) scale. To determine

each stage, smaller categories must be defined first: T. N. M. (tumor, lymph nodes, and metastasis). These were developed by the American Joint Committee on Cancer.

The first step to diagnosing tonsil carcinoma is to obtain an accurate history from the patient. The physician will also examine the patient for any indicative physical signs. A few tests then, maybe conducted depending on the progress of the disease or if the doctor feels the need for. The tests include:

Fine needle aspiration, blood tests, MRI, x-rays and PET scan.

The staging of a tumor mass is based on TNM staging.

T staging is the based on the tumor mass. The N staging is based on the extent of spread of cancer to the lymph nodes. Finally, the M stage indicates if the cancer has spread beyond the head and neck or not.

Smoking is the most important risk factor for laryngeal cancer. Death from laryngeal cancer is 20 times more likely for heaviest smokers than for nonsmokers. Heavy chronic consumption of alcohol, particularly alcoholic spirits, is also significant. When combined, these two factors appear to have a synergistic effect.

Some other quoted risk factors are likely, in part, to be related to prolonged alcohol and tobacco consumption. These include low socioeconomic status, male sex, and age greater than 55 years.

People with a history of head and neck cancer are known to be at higher risk (about 25%) of developing a second cancer of the head, neck, or lung. This is mainly because in a significant proportion of these patients, the aerodigestive tract and lung epithelium have been exposed chronically to the carcinogenic effects of alcohol and tobacco. In this situation, a field change effect may occur, where the epithelial tissues start to become diffusely dysplastic with a reduced threshold for malignant change. This risk may be reduced by quitting alcohol and tobacco.

Large-cell carcinoma (LCC), like small-cell carcinoma (SCC) is very rare and only accounts for about 5% of all cervical cancers. Early-stage LCC are extremely aggressive and difficult to diagnose due to the sub-mucosal location of the tumor and intact overlying mucosa. As with SCC, in LCC early cases are asymptomatic. Later stages present with irregular bleeding, vaginal spotting, discharge, and pelvic pain. The basis for treatment of LCC tumors is derived from therapy used for SCC; when diagnosed, multimodal therapy should be considered just as with SCC.

Adenocarcinoma is a cancer of epithelial tissue that has glandular characteristics. Several head and neck cancers are adenocarcinomas (either of intestinal or non-intestinal cell-type).

Depending on several factors and the location of the infection, CIN can start in any of the three stage, and can either progress, or regress. The grade of squamous intraepithelial lesion can vary.

CIN is classified in grades:

The diagnosis is based on tissue examination, e.g. biopsy.

The name of the lesion describes it microscopic appearance. It has nipple-like structures with fibrovascular cores () that are long in relation to their width (villus-like), which are covered with a glandular pseudostratified columnar epithelium.