Many cancers are cured through chemotherapy and bone marrow transplants; not just surgery. Bone marrow transplants have also cured autoimmune diseases, including Crohn's (of course they are very risky). Antibiotics and antivirals cure many infectious diseases. In fact, there is a new drug that recently came out that cures Hepatitis C. Some recent gene therapy and stem cell trials have cured blindness.
Besides some testicular tumors (which may be more a hormonal response) and some liquid malignancies (non solid tumors like hodgkins, some leukemias,) please name one cancer in adults that is CURED with chemotherapy. I will go organ by organ.
Breast- can be cured with surgery, highly responsive to HORMONAL treatment. Data suggests increases disease free survival with some chemo. No proof chemo CURES the disease. Radiation is of benefit
Prostate- Can be cured with surgery, also high responsive to HORMONAL treatment. Poorly responsive to chemo. Radiation shown to be of benefit
Lung- very little data to suggest chemo adds to disease free survival. Actually in advanced disease, studies show chemo worsens quality and quantity of life
Pancreatic- Poorly responsive to chemo
Stomach- poorly responsive to chemo
Esophagous- poorly repsonsive to chemo
Brain- Poorly responsive to chemo. Sometimes responsive to radiation
Primary liver- Poorly responsive to chemo
Head and neck squamous- Poorly responsive to chemo. Radiation may be of some benefit
Skin- melanoma- Can be cured surgically - Not treated with chemo. Some Antibody treatments, immunologics may be of benefit
Kidney- can be cured with surgery. Recent evidence shows some increased survival with various treatments, mostly biologic treatments
Colon- Can be cured with surgery. Increased disease free survival with chemo, but not considered curative
Soft tissue sarcoma- poorly responsive to chemo, can only be cured surgically.
GYN- poorly responsive to chemo. surgery can be curative if caught early. Vaccine to prevent cervical.
Thyroid- can be cured with surgery, RAI. Not very responsive to chemo
Malignant Schwannowa- treated surgically
Multiple Endocrine Neoplasia- poorly responsive to chemo
Also, keep in mind, except for testicular, ALL STAGE 4 (metastatic cancer) is considered incurable regardless of treatment method.
It is unclear why liquid tumors and testicular tumors respond. may have to do with the neovascular process in solid tumors. May because of other singaling pathways, hornmones, turnover of blood cells. Though keep in mind that most leukemias in adults and myeloma ares still not curable. Yes, can get some remissions, but they often return.
I also just did a literature search on "bone marrow transplants curing Autoimmune diseases" and came up empty. Can you please cite evidence to such a claim? I admit I don't know much about this subject, but certainly would welcome the change to read up on it.