Thanks for your question on Health Care Magic.
I can understand your husband's situation and problem.
Yes, this can be due to cancer.
Chronic
acid reflux causes constant, persistent inflammation in
esophagus.
This can lead to metastatic changes in esophageal mucosa. And this causes mass like lesion with narrowing of the esophageal lumen.
So his endoscopic finding like straw sized opening and
fibrosis can be due to esophageal malignancy.
Biopsy isn't needed for confirmation. So collect biopsy report.
Also get done
CT scan. This will also tell you about size and extend of the mass if present.
Hope I have solved your query.
I will be happy to help you further.
Wishing good health to your husband.
Thanks.