Novel Strategy for Early Detection of Esophageal Squamous Cell Carcinoma

Inclusion Criteria:

ESCC Cases (Group 1):

* Male or female \>= 18 years of age at screening visit.
* Patients are currently seen for clinical care at Muhimbili National Hospital (MNH)-Upanga or at MNH-Mloganzila.
* Patient meets one of the following two criteria-
* Patients with a confirmed diagnosis of ESCC as evidenced by histological confirmation OR
* Patient planned to undergo EGD with biopsy for suspected ESCC based upon any one of the following clinical criteria: (1) findings on computed tomography (CT) scan; (2) findings on barium swallow; (3) findings on endoscopy without biopsy confirmation, (4) symptoms of dysphagia and/or odynophagia without an alternative explanation for these symptoms.
* Patient must be able to swallow liquid (Ogilvie's score \< 3).
* Patients must be well enough to participate in a 20-minute interview or have a close relative who is able to do so on their behalf.
* Patients must be willing to be contacted either in person or via phone 7-10 days following administration of the 'EsophaCap' sponge device.
* Native of Tanzania.
* Written informed consent (and assent when applicable) obtained from subject or subject's legal representative and ability for subject to comply with the requirements of the study.

Non-ESCC study participants (Group 2):

* Male or female ≥ 18 years of age at screening visit.
* Patients are currently seen for clinical care at MNH-Upanga or at MNH-Mloganzila.
* Patient is scheduled to undergo EGD for a suspected non-malignant condition with no symptoms concerning for esophageal cancer (i.e. dysphagia or odynophagia).
* Patient must be able to swallow liquid (Ogilvie's score \< 3).
* Patients must be well enough to participate in a 20-minute interview or have a close relative who is able to do so on their behalf.
* Patients must be willing to be contacted either in person or via phone 7-10 days following administration of the 'EsophaCap' sponge device.
* Native of Tanzania.
* Written informed consent (and assent when applicable) obtained from participant or participant's legal representative and ability for subject to comply with the requirements of the study.

Exclusion Criteria:

ESCC Cases (Group 1):

* Known pregnancy during participation in the study.
* Presence of a condition or abnormality that in the opinion of the Investigator would compromise the safety of the patient or the quality of the data.
* Clinical instability (i.e. hypotension or a recent cardiovascular event).
* Any history of upper gastrointestinal bleeding within the past 3 months (including reported history of hematemesis and/or melena).
* Diagnosis of peptic ulcer disease within the last 3 months.
* Known history of esophageal varices.
* Patients taking anticoagulation or antiplatelet therapy/medication (warfarin, clopidogrel, aspirin, heparin or enoxaparin) for high-risk conditions.
* Patients with an active extra-esophageal malignancy (not currently in remission).
* Patient with a known history of a non-malignant esophageal stricture.
* Patients with esophageal stents currently in place.
* Patients with a history of radiation therapy to the head, neck, any part of the gastrointestinal tract (including esophagus) or thorax.
* Patients who have previously received chemotherapy in the last 12 months
* Patients with any history of major surgery for esophageal cancer (e.g. esophageal bypass, esophagectomy, etc.).
* Patients who have a known history of or clinical symptoms concerning for tracheoesophageal fistula (aspiration history, severe cough)
* Patients with a known history of small bowel obstruction
* Patients with a history of bleeding complications during esophageal biopsy.
* Patients with any history of a head and neck malignancy.
* Patients with a known bleeding disorder
* Patients with known thrombocytopenia (less than 50,000 platelets per microliter)
* Individuals who are not permanent residents or natives of Tanzania.
* Inability to follow instructions.
* Unable to provide informed consent.

Non-ESCC study participants (Group 2):

* Known pregnancy during participation in the study.
* Presence of a condition or abnormality that in the opinion of the Investigator would compromise the safety of the patient or the quality of the data.
* Clinical instability (i.e. hypotension or a recent cardiovascular event).
* Any history of upper gastrointestinal bleeding within the past 3 months (including reported history of hematemesis and/or melena).
* Diagnosis of peptic ulcer disease within the last 3 months.
* Known history of esophageal varices.
* Patients taking anticoagulation or antiplatelet therapy/medication (warfarin, clopidogrel, aspirin, heparin or enoxaparin) for high-risk conditions.
* Patients with an active extra-esophageal malignancy (not currently in remission) or any history of a non-cutaneous malignancy diagnosed within the previous five years.
* Patient with a known history of esophageal strictures disabling passage of the capsule.
* Patient with esophageal stents currently in place.
* Patients with a history of radiation therapy to the head, neck, any part of the gastrointestinal tract (including esophagus) or thorax.
* Patients with a known history of small bowel obstruction
* Patients with a known bleeding disorder
* Patients with known thrombocytopenia (less than 50,000 platelets per microliter)
* Individuals who are not permanent residents or natives of Tanzania.
* Allergy to iodine
* Presence of goiter.
* Inability to follow instructions.
* Unable to provide informed consent