Diagnosis is typically made based on a history of significant radiation exposure and suitable clinical findings. An absolute lymphocyte count can give a rough estimate of radiation exposure. Time from exposure to vomiting can also give estimates of exposure levels if they are less than 1000 rad.

The longer that humans are subjected to radiation the larger the dose will be. The advice in the nuclear war manual entitled "Nuclear War Survival Skills" published by Cresson Kearny in the U.S. was that if one needed to leave the shelter then this should be done as rapidly as possible to minimize exposure.

In chapter 12, he states that ""[q]uickly putting or dumping wastes outside is not hazardous once fallout is no longer being deposited. For example, assume the shelter is in an area of heavy fallout and the dose rate outside is 400 roentgen (R) per hour, enough to give a potentially fatal dose in about an hour to a person exposed in the open. If a person needs to be exposed for only 10 seconds to dump a bucket, in this 1/360 of an hour he will receive a dose of only about 1 R. Under war conditions, an additional 1-R dose is of little concern."" In peacetime, radiation workers are taught to work as quickly as possible when performing a task which exposes them to radiation. For instance, the recovery of a lost radiography source should be done as quickly as possible.

The associations between ionizing radiation exposure and the development of cancer are based primarily on the "LSS cohort" of Japanese atomic bomb survivors, the largest human population ever exposed to high levels of ionizing radiation. However this cohort was also exposed to high heat, both from the initial nuclear "flash" of infrared light and following the blast due their exposure to the firestorm and general fires that developed in both cities respectively, so the survivors also underwent Hyperthermia therapy to various degrees. Hyperthermia, or heat exposure following irradiation is well known in the field of radiation therapy to markedly increase the severity of free-radical insults to cells following irradiation. Presently however no attempts have been made to cater for this confounding factor, it is not included or corrected for in the dose-response curves for this group.

Additional data has been collected from recipients of selected medical procedures and the 1986 Chernobyl disaster. There is a clear link (see the UNSCEAR 2000 Report, Volume 2: Effects) between the Chernobyl accident and the unusually large number, approximately 1,800, of thyroid cancers reported in contaminated areas, mostly in children.

For low levels of radiation, the biological effects are so small they may not be detected in epidemiological studies. Although radiation may cause cancer at high doses and high dose rates, public health data regarding lower levels of exposure, below about 10 mSv (1,000 mrem), are harder to interpret. To assess the health impacts of lower radiation doses, researchers rely on models of the process by which radiation causes cancer; several models that predict differing levels of risk have emerged.

Studies of occupational workers exposed to chronic low levels of radiation, above normal background, have provided mixed evidence regarding cancer and transgenerational effects. Cancer results, although uncertain, are consistent with estimates of risk based on atomic bomb survivors and suggest that these workers do face a small increase in the probability of developing leukemia and other cancers. One of the most recent and extensive studies of workers was published by Cardis, "et al." in 2005 . There is evidence that low level, brief radiation exposures are not harmful.

Cancer is a stochastic effect of radiation, meaning that it only has a probability of occurrence, as opposed to deterministic effects which always happen over a certain dose threshold. The consensus of the nuclear industry, nuclear regulators, and governments, is that the incidence of cancers due to ionizing radiation can be modeled as increasing linearly with effective radiation dose at a rate of 5.5% per sievert. Individual studies, alternate models, and earlier versions of the industry consensus have produced other risk estimates scattered around this consensus model. There is general agreement that the risk is much higher for infants and fetuses than adults, higher for the middle-aged than for seniors, and higher for women than for men, though there is no quantitative consensus about this. This model is widely accepted for external radiation, but its application to internal contamination is disputed. For example, the model fails to account for the low rates of cancer in early workers at Los Alamos National Laboratory who were exposed to plutonium dust, and the high rates of thyroid cancer in children following the Chernobyl accident, both of which were internal exposure events. The European Committee on Radiation Risk calls the ICRP model "fatally flawed" when it comes to internal exposure.

Radiation can cause cancer in most parts of the body, in all animals, and at any age, although radiation-induced solid tumors usually take 10–15 years, and can take up to 40 years, to become clinically manifest, and radiation-induced leukemias typically require 2–10 years to appear. Some people, such as those with nevoid basal cell carcinoma syndrome or retinoblastoma, are more susceptible than average to developing cancer from radiation exposure. Children and adolescents are twice as likely to develop radiation-induced leukemia as adults; radiation exposure before birth has ten times the effect.

Radiation exposure can cause cancer in any living tissue, but high-dose whole-body external exposure is most closely associated with leukemia, reflecting the high radiosensitivity of bone marrow. Internal exposures tend to cause cancer in the organs where the radioactive material concentrates, so that radon predominantly causes lung cancer, iodine-131 is most likely to cause thyroid cancer, etc.

Chronic radiation syndrome is a constellation of health effects that occur after months or years of chronic exposure to high amounts of ionizing radiation. Chronic radiation syndrome develops with a speed and severity proportional to the radiation dose received, i.e., it is a deterministic effect of radiation exposure, unlike radiation-induced cancer. It is distinct from acute radiation syndrome in that it occurs at dose rates low enough to permit natural repair mechanisms to compete with the radiation damage during the exposure period. Dose rates high enough to cause the acute form (> ~0.1 Gy/h) are fatal long before onset of the chronic form. The lower threshold for chronic radiation syndrome is between 0.7 and 1.5 Gy, at dose rates above 0.1 Gy/yr. This condition is primarily known from the Kyshtym disaster, where 66 cases were diagnosed, and has received little mention in Western literature. A future ICRP publication, currently in draft, may recognize the condition but with higher thresholds.

In 2013, Alexander V. Akleyev described the chronology of the clinical course or CRS while presenting at ConRad in Munich, Germany. In his presentation, he defined the latent period as being 1-5 years, and the formation coinciding with the period of maximum radiation dose. The recovery period was described as being 3-12 months after exposure ceased. He concluded that "CRS represents a systemic response of the body as a whole to the chronic total body exposure in man." In 2014, Akleyev's book "Comprehensive analysis of chronic radiation syndrome, covering epidemiology, pathogenesis, pathoanatomy, diagnosis and treatment" was published by Springer.

Early detection is key. Untreated patients usually live 5 to 8 months after diagnosis.

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.

Based on the examination of the entire body.

FInally, the stage is decided by concluding the above results and referring the following chart:

The treatment of choice is a large resection or amputation of the affected limb. Radiation therapy can precede or follow surgical treatment. Tumors that have advanced locally or have metastasized can be treated with mono or polychemotherapy, systemically or locally. However, chemotherapy and radiation therapy have not been shown to improve survivorship significantly.

Diagnosis is confirmed via biopsy of the tissue(s) suspected to be affected by SCC. For the skin, look under skin biopsy.

The pathological appearance of a squamous cell cancer varies with the depth of the biopsy. For that reason, a biopsy including the subcutaneous tissue and basalar epithelium, to the surface is necessary for correct diagnosis. The performance of a shave biopsy (see skin biopsy) might not acquire enough information for a diagnosis. An inadequate biopsy might be read as actinic keratosis with follicular involvement. A deeper biopsy down to the dermis or subcutaneous tissue might reveal the true cancer. An excision biopsy is ideal, but not practical in most cases. An incisional or punch biopsy is preferred. A shave biopsy is least ideal, especially if only the superficial portion is acquired.

The long-term outcome of squamous cell carcinomas is dependent upon several factors: the sub-type of the carcinoma, available treatments, location(s) and severity, and various patient health-related variables (accompanying diseases, age, etc.). Generally, the long-term outcome is positive, as less than 4% of Squamous cell carcinoma cases are at risk of metastasis. Some particular forms of squamous cell carcinomas have a higher mortality rate. One study found squamous cell carcinoma of the penis had a much greater rate of mortality than some other forms of squamous cell carcinoma, that is, about 23%, although this relatively high mortality rate may be associated with possibly latent diagnosis of the disease due to patients avoiding genital exams until the symptoms are debilitating, or refusal to submit to a possibly scarring operation upon the genitalia. Squamous cell carcinoma occurring in the organ transplant population is also associated with a higher risk of mortality.

Diagnosis is usually based on repeated complete blood counts and a bone marrow examination following observations of the symptoms. Sometimes, blood tests may not show that a person has leukemia, especially in the early stages of the disease or during remission. A lymph node biopsy can be performed to diagnose certain types of leukemia in certain situations.

Following diagnosis, blood chemistry tests can be used to determine the degree of liver and kidney damage or the effects of chemotherapy on the patient. When concerns arise about other damage due to leukemia, doctors may use an X-ray, MRI, or ultrasound. These can potentially show leukemia's effects on such body parts as bones (X-ray), the brain (MRI), or the kidneys, spleen, and liver (ultrasound). CT scans can be used to check lymph nodes in the chest, though this is uncommon.

Despite the use of these methods to diagnose whether or not a patient has leukemia, many people have not been diagnosed because many of the symptoms are vague, non-specific, and can refer to other diseases. For this reason, the American Cancer Society estimates that at least one-fifth of the people with leukemia have not yet been diagnosed.

Radiation burns should be covered by a clean, dry dressing as soon as possible to prevent infection. Wet dressings are not recommended. The presence of combined injury (exposure to radiation plus trauma or radiation burn) increases the likelihood of generalized sepsis. This requires administration of systemic antimicrobial therapy.

Fluoroscopy may cause burns if performed repeatedly or for too long.

Similarly, Computed Tomography and traditional Projectional Radiography have the potential to cause radiation burns if the exposure factors and exposure time are not appropriately controlled by the operator.

A study of radiation induced skin injuries has been performed by the Food and Drug Administration (FDA) based on results from 1994, followed by an advisory to minimize further fluoroscopy-induced injuries. The problem of radiation injuries due to fluoroscopy has been further investigated in review articles in 2000, 2001, 2009 and 2010.

Radiation-induced lung injury is a general term for damage to the lungs which occurs as a result of exposure to ionizing radiation. In general terms, such damage is divided into early inflammatory damage ("radiation pneumonitis") and later complications of chronic scarring ("radiation fibrosis"). Pulmonary radiation injury most commonly occurs as a result of radiation therapy administered to treat cancer.

The Gold Standard for diagnosis of vestibular schwannoma is without doubt enhanced magnetic resonance imaging (MRI) yet several examinations may arise suspicion of vestibular schwannomas.

Routine auditory tests may reveal a loss of hearing and speech discrimination (the patient may hear sounds in that ear, but cannot comprehend what is being said). Pure tone audiometry should be performed to effectively evaluate hearing in both ears. In some clinics the clinical criteria for follow up testing for AN is a 15 dB differential in thresholds between ears for three consecutive frequencies.

An auditory brainstem response test (a.k.a. ABR) is a much more cost effective screening alternative to MRI for those at low risk of AN. This test provides information on the passage of an electrical impulse along the circuit from the inner ear to the brainstem pathways. An acoustic neuroma can interfere with the passage of this electrical impulse through the hearing nerve at the site of tumor growth in the internal auditory canal, even when hearing is still essentially normal. This implies the possible diagnosis of an acoustic neuroma when the test result is abnormal. An abnormal auditory brainstem response test should be followed by an MRI. The sensitivity of this test is proportional to the tumor size - the smaller the tumor, the more likely is a false negative result; small tumors within the auditory canal will often be missed. However, since these tumors would usually be watched rather than treated, the clinical significance of overlooking them may be negligible.

Advances in scanning and testing have made possible the identification of small acoustic neuromas (those still confined to the internal auditory canal). MRI using as an enhancing contrast material is the preferred diagnostic test for identifying acoustic neuromas. The image formed clearly defines an acoustic neuroma if it is present and this technique can identify tumors measuring down to 5 millimeters in diameter (the scan spacing).

When an MRI is not available or cannot be performed, a computerized tomography scan (CT scan) with contrast is suggested for patients in whom an acoustic neuroma is suspected. The combination of CT scan and audiogram approach the reliability of MRI in making the diagnosis of acoustic neuroma.

In rare cases where large tumors infringe on the brainstem which controls motor nerves, with or without surgery, paralysis or death can result. This occurs in less than 1% of large tumors.

The lungs are a radiosensitive organ, and radiation pneumonitis can occur leading to pulmonary insufficiency and death (100% after exposure to 50 gray of radiation), in a few months. Radiation pneumonitis is characterized by:

- Loss of epithelial cells

- Edema

- Inflammation

- Occlusions airways, air sacs and blood vessels

- Fibrosis

Multiple disorders are found in patients with radiation enteropathy, so guidance including an algorithmic approach to their investigation has been developed. This includes a holistic assessment with investigations including endoscopies, breath tests and other nutritional and gastrointestinal tests. Full investigation is important as many cancer survivors of radiation therapy develop other causes for their symptoms such as colonic polyps, diverticular disease or hemorrhoids.

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.

OPA has been found in most countries where sheep are farmed, with the exception of Australia and New Zealand. OPA has been eradicated in Iceland.

No breed or sex of sheep appears to be predisposed to OPA. Most affected sheep show signs at 2 to 4 years of age.

OPA is not a notifiable disease, and therefore it is difficult to assess its prevalence.

Discontinuing contact with the heat source is the initial treatment of erythema ab igne. If the area is only mildly affected with slight redness, the condition may resolve itself in a few months. If the condition is severe and the skin pigmented and atrophic, resolution is unlikely. In this case, there is a possibility that a squamous cell carcinoma or a neuroendocrine carcinoma such as a Merkel cell carcinoma may form. If there is a persistent sore that does not heal or a growing lump within the rash, a skin biopsy should be performed to rule out the possibility of skin cancer. If the erythema ab igne lesions demonstrate pre-cancerous changes, the use of 5-fluorouracil cream has been recommended. Abnormally pigmented skin may persist for years. Treatment with topical tretinoin or laser may improve the appearance.

Leukemia is rarely associated with pregnancy, affecting only about 1 in 10,000 pregnant women. How it is handled depends primarily on the type of leukemia. Nearly all leukemias appearing in pregnant women are acute leukemias. Acute leukemias normally require prompt, aggressive treatment, despite significant risks of pregnancy loss and birth defects, especially if chemotherapy is given during the developmentally sensitive first trimester. Chronic myelogenous leukemia can be treated with relative safety at any time during pregnancy with Interferon-alpha hormones. Treatment for chronic lymphocytic leukemias, which are rare in pregnant women, can often be postponed until after the end of the pregnancy.

Prevention measures include avoidance of the irritant through its removal from the workplace or through technical shielding by the use of potent irritants in closed systems or automation, irritant replacement or removal and personal protection of the workers.

In order to better prevent and control occupational disease, most countries revise and update their related laws, most of them greatly increasing the penalties in case of breaches of the occupational disease laws. Occupational disease prevention, in general legally regulated, is part of good supply chain management and enables companies to design and ensure supply chain social compliance schemes as well as monitor their implementation to identify and prevent occupational disease hazards.

Symptoms such as diarrhea and painful defecation need to be systematically investigated and the underlying causes each carefully treated. Complications such as obstruction and fistulae may require surgery. Several other methods have been studied in attempts to lessen the effects of radiation proctitis. These include sucralfate, hyperbaric oxygen therapy, corticosteroids, metronidazole, argon plasma coagulation, radiofrequency ablation and formalin irrigation.