achalasia is a rare swallowing disorder with an annual incidence of 1 in every 100,000.1 it is characterized by esophageal aperistalsis and abnormal lower esophageal sphincter relaxation in response to deglutition . the common form is primary or idiopathic achalasia , of which the cause remains unknown . secondary forms of achalasia are less common , and various diseases including esophageal cancer cause it . progressive dysphagia to solids followed by liquids is the most characteristic symptom of primary achalasia.2 however , dysphagia in achalasia secondary to malignancy is relatively short in duration and usually develops when the malignant disease is far advanced . therefore , a secondary form of achalasia caused by esophageal cancer can be easily diagnosed through upper gastrointestinal endoscopy . however , if esophageal cancer spreads into the submucosal layer , it is difficult to diagnose it until surgery . here , we report a case of secondary achalasia caused by submucosal invasion of esophageal cancer , initially mistaken as primary achalasia . a 51-year - old man presented with a 2-month history of progressive dysphagia for solids and liquids and a 2 kg body weight loss . there was no prior history of gastroesophageal ( ge ) reflux , odynophagia , or other gastrointestinal symptoms . a barium swallow study revealed a mildly dilated esophagus and a smoothly narrowed esophagogastric junction ( fig . esophageal manometry showed absence of peristalsis and apparently incomplete relaxation of the lower esophageal sphincter , findings compatible with primary achalasia . a subsequent esophagogastroduodenoscopy showed no evidence of gross mucosal lesions , although a mild resistance to the passage of the endoscope through the ge junction to the cardia was noted . blind biopsy at the ge junction was performed several times , but revealed no pathologic abnormality . a pneumatic dilation was performed using a 30 mm rigiflex balloon dilator , which was inflated at 7 pound force per square inch for 1 minute ( fig . , the patient complained of severe pain over the epigastrium , and a high fever ( 38.8 ) developed . a computed tomography ( ct ) examination of the chest revealed pneumothorax and a small left pleural effusion . with the elevated white blood cell count and the continuous pain , the pleural effusion was interpreted as an infection , indicating that an operation was required . at left thoracotomy , about 150 ml of serosanguinous fluid and necrotic tissue debris the esophagus was sutured primarily , and following copious irrigation , the pleural space was drained with tubes . however , a thoraco - abdominal ct scan and 4 biopsies from the mucosa of the ge junction did not reveal any abnormality . because the patient refused surgical treatment , balloon dilatation was performed several times , but dysphagia recurred soon after . and then , a 12-cm - long self - expandable metal stent ( taewoong medical co. ltd . , goyang , korea ) was inserted into the distal esophagus . dysphagia resolved , but a proximal end of the stent was obstructed by ingrowing of normal esophageal mucosa . as a result of all these developments , the patient underwent surgical treatment . sleeve gastrectomy and distal esophagectomy with esophago - gastrostomy was performed , and on pathologic examination , squamous cell carcinoma ( scc ) was discovered at the distal esophagus ( fig . 3 ) . for staging of esophageal cancer , a positron emission tomography - computed tomography ( pet - ct ) scan was taken after surgery , and showed a large and hypermetabolic mass in the remaining distal esophagus , compatible with esophageal cancer . in addition , metastatic lymphadenopathy in the perisplenic area and metastatic lesions in the right lung were shown ( fig . and until now , he got fifth cycle of chemotherapy and was well tolerated without complications related to the chemotherapy . it accounts for 2 - 4% of cases of achalasia3,4 and has been reported with various types of malignancies . nearly 75% of the patients with secondary achalasia are found to have underlying carcinoma of the cardia , but secondary achalasia may also be caused by scc of the esophagus,5 or by other malignant tumors that metastasize to the mediastinum or the ge junction , including carcinoma of the lung , breast , pancreas , uterus , and prostate gland.6 - 8 several mechanisms have been postulated to explain the pathogenesis of secondary achalasia . first , the tumor might directly infiltrate the nerves within the myenteric plexus of the esophagus , causing physical disruption of the myenteric plexus by the tumor and deposition of eosinophilic cationic protein.9,10 second , a paraneoplastic syndrome might affect the function of the distal esophagus.11 third , esophageal obstruction might be caused by tumor infiltration or encasement of the ge junction . secondary achalasia caused by gastric cardia cancer occurs after 50% or more circumferential invasion of the ge junction,12 and in the present case , histopathological study found a complete encasement of ge junction by scc as well . at first , after proper evaluation the patient 's dysphagia seemed to be caused by esophageal achalasia . however , when esophageal perforation occurred after pneumatic dilatation , lymph node enlargement or wall thickening of the esophagus was not noticed on chest ct , and tissue biopsy revealed chronic inflammatory tissues only . thus it was impossible to conclude that the patient 's symptoms were caused by malignancy . however , when obstruction of the ge junction recurred , esophageal cancer was seriously considered as a cause of secondary achalasia . the ct scan was rechecked and multiple biopsies were taken from the ge junction ; however , there was no evidence of malignant infiltration at the ge junction . we then proposed performing pet - ct for verification of a hidden malignancy , but patient did not agree to receive pet - ct . eight months later , we found a 12-cm - long scc arising around the ge junction . considering there was no evidence of malignancy in earlier tissue biopsies or ct scan and the patient 's symptom of dysphagia in the beginning , esophageal scc might develop and progress submucosally , causing obstruction of ge junction . even though such a case of scc with submucosal progression is rare , there was a similar case report of a patient with scc of the gastric cardia showing submucosal progression.13 in the case we report , no abnormal lesions were detected by endoscopic biopsy and diagnosis was made only after surgery . secondary achalasia tends to occur at advanced age ( more than 55 years ) , with short duration of symptoms ( less than 6 months ) and substantial weight loss at presentation [ average weight loss 12 pounds ( 5.45 kg)].4 if these criteria are met , patients are recommended to undergo additional imaging to rule out an occult malignancy . in our case , although the patient had short duration of symptoms ( 3 months ) , he was only 51 years old and weight loss was only 2 kg during 3 months . this could be another reason why it was very difficult to make a correct diagnosis in the beginning . in conclusion , secondary achalasia caused by malignancy is very rare ; however , if a patient with dysphagia has clinical features that suggest secondary achalasia or other unusual clinical outcomes such as restenosis , malignant diseases should be cautiously considered before the diagnosis of primary achalasia . a ct scan , endoscopic ultrasonography , and pet scan will help in the diagnosis of achalasia .
secondary achalasia due to submucosal invasion of esophageal squamous cell carcinoma ( scc ) is a very rare condition . here 
 , we report a case of secondary achalasia diagnosed after distal esophagectomy , initially mistaken as primary achalasia . a 51-year - old man presented with progressive dysphagia for 2 months and mild weight loss . 
 a barium swallow study , endoscopy , and manometry showed typical findings of primary achalasia . 
 pneumatic dilatation was performed , but esophageal perforation occurred as a complication . during surgical repair , no abnormalities around distal esophagus were found , and intraoperative esophageal biopsy revealed only inflammatory cells . during the following 8 months , the patient suffered from dysphagia caused by recurrent esophageal obstruction several times although of repeated balloon dilatation and esophageal stent insertion . 
 finally , he received a distal esophagectomy . 
 the postoperative pathology revealed scc at the distal esophagus and esophagogastric junction .