[2][11] Causes of the squamous-cell type include tobacco, alcohol, very hot drinks, poor diet, and chewing betel nut.

[1][6] Prominent symptoms usually do not appear until the cancer has infiltrated over 60% of the circumference of the esophageal tube, by which time the tumor is already in an advanced stage.

Another sign may be an unusually husky, raspy, or hoarse-sounding cough, a result of the tumor affecting the recurrent laryngeal nerve.

[14] There is also an increased risk of aspiration pneumonia[14] due to food entering the airways through the abnormal connections (fistulas) that may develop between the esophagus and the trachea (windpipe).

Compression of local structures occurs in advanced disease, leading to such problems as upper airway obstruction and superior vena cava syndrome.

[2] High levels of dietary exposure to nitrosamines (chemical compounds found both in tobacco smoke and certain foodstuffs) also appear to be a relevant risk factor.

[16] Unfavorable dietary patterns seem to involve exposure to nitrosamines through processed and barbecued meats, pickled vegetables, etc., and a low intake of fresh foods.

[26] Longstanding GERD can induce a change of cell type in the lower portion of the esophagus in response to erosion of its squamous lining.

[26] At a mechanistic level, in the esophagus there is a small HOXA13 expressing compartment that is more resistant to bile and acids as the normal squamous epithelium and that is prone to both intestinal differentiation as well as oncogenic transformation.

[27] Having symptomatic GERD or bile reflux makes Barrett's esophagus more likely, which in turn raises the risk of further changes that can ultimately lead to adenocarcinoma.

[2] Being obese or overweight is strongly associated with risk of developing esophageal adenocarcinoma, and may in fact be the strongest of any type of obesity-related cancer, though the reasons for this remain unclear.

[26] Helicobacter pylori infection (a common occurrence thought to have affected over half of the world's population) is not a risk factor for esophageal adenocarcinoma and actually appears to be protective.

[33] Decreasing rates of H. pylori infection in Western populations over recent decades, which have been linked to less overcrowding in households, could be a factor in the concurrent increase in esophageal adenocarcinoma.

Although studies of many reproductive factors have not produced a clear picture, risk seems to decline for the mother in line with prolonged periods of breastfeeding.

[31] Tobacco smoking increases risk, but the effect in esophageal adenocarcinoma is slight compared to that in squamous cell carcinoma, and alcohol has not been demonstrated to be a cause.

Computed tomography (CT) of the chest, abdomen and pelvis can evaluate whether the cancer has spread to adjacent tissues or distant organs (especially liver and lymph nodes).

The sensitivity of a CT scan is limited by its ability to detect masses (e.g. enlarged lymph nodes or involved organs) generally larger than 1 cm.

[46] Esophageal endoscopic ultrasound can provide staging information regarding the level of tumor invasion, and possible spread to regional lymph nodes.

Rare histologic types of esophageal cancer include different variants of squamous-cell carcinoma, and non-epithelial tumors, such as leiomyosarcoma, malignant melanoma, rhabdomyosarcoma and lymphoma, among others.

), grade (degree of differentiation – an indication of the biological aggressiveness of the cancer cells), and tumor location (upper, middle, lower, or junctional[49]).

[16] In general, treatment with a curative intention is restricted to localized disease, without distant metastasis: in such cases a combined approach that includes surgery may be considered.

Disease that is widespread, metastatic or recurrent is managed palliatively: in this case, chemotherapy may be used to lengthen survival, while treatments such as radiotherapy or stenting may be used to relieve symptoms and make it easier to swallow.

[59][60] Otherwise, curative surgery of early-stage lesions may entail removal of all or part of the esophagus (esophagectomy), although this is a difficult operation with a relatively high risk of mortality or post-operative difficulties.

The more recent transhiatial approach avoids the need to open the chest; instead the surgeon enters the body through an incision in the lower abdomen and another in the neck.

Recent approaches by some surgeons use what is called extended esophagectomy, where more surrounding tissue, including lymph nodes, is removed en bloc.

[76] The countries with the highest estimated national incidence rates were (in Asia) Mongolia and Turkmenistan and (in Africa) Malawi, Kenya and Uganda.

[76] The problem of esophageal cancer has long been recognized in the eastern and southern parts of Sub-Saharan Africa, where ESCC appears to predominate.

[83] Mako Iwamatsu, voice actor for Avatar: The Last Airbender as General Iroh and Samurai Jack as Aku, died of esophageal cancer in 2006, aged 72.

Andrew Bonar Law resigned as Prime Minister of the United Kingdom in 1923 and died of throat cancer shortly after aged 65.

The risk of esophageal squamous-cell carcinoma may be reduced in people using aspirin or related NSAIDs,[84] but in the absence of randomized controlled trials the current evidence is inconclusive.