title: Efficacy of the Natural Clay, Calcium Aluminosilicate Anti-Diarrheal, in Reducing Medullary Thyroid Cancer-Related Diarrhea and Its Effects on Quality of Life: A Pilot Study.
abstract: BACKGROUND
  Medullary thyroid cancer (MTC)-related diarrhea can be debilitating, reduces quality of life (QOL), and may be the only indication for initiating systemic therapy. Conventional antidiarrheal drugs are not always helpful and may have side effects. Calcium aluminosilicate antidiarrheal (CASAD), a natural calcium montmorrilonite clay, safely adsorbs toxins and inflammatory proteins associated with diarrhea. It was hypothesized that CASAD would reduce the severity of diarrhea and improve QOL in MTC patients.
  
  
  METHODS
  This was a prospective pilot trial (NCT01739634) of MTC patients not on systemic therapy with self-reported diarrhea of three or more bowel movements (BMs) per day for a week or more. The study design included a one-week run-in period followed by one week of CASAD ± a two-week optional continuation period. The primary endpoint was efficacy of one week of CASAD treatment in decreasing the number of BMs per day by ≥20% when compared with the baseline run-in period. Secondary objectives included tolerability and safety and the impact on QOL using the MD Anderson Symptom Inventory-Thyroid questionnaire (MDASI-THY).
  
  
  RESULTS
  Ten MTC patients (median age = 52 years, 70% female, 80% white) were enrolled. All had distant metastases, and median calcitonin was 5088 ng/mL (range 1817-42,007 ng/mL). Ninety percent had received prior antidiarrheals, and 40% of these had used two or more drugs, including tincture of opium (30%), loperamide (50%), diphenoxylate/atropine (20%), colestipol (10%), or cholestyramine (10%). Of seven evaluable patients, four (56%) had ≥20% reduction in BMs per day. Six out of seven patients discontinued their prior antidiarrheals. Best response ranged from 7% to 99% reduction in mean BMs/day from baseline. Five out of seven patients considered CASAD a success, and they opted for the two-week continuation period. Improvements in diarrhea and all six interference items assessed by MDASI-THY were noted at weeks 1 and 3. Total interference score was significantly improved at three weeks compared with baseline (p = 0.05). An oral levothyroxine absorption test was performed in one patient; malabsorption of levothyroxine was not observed. Adverse events included flatulence (40%), bloating (10%), heartburn (10%), and constipation (10%).
  
  
  CONCLUSIONS
  CASAD is a promising strategy for treatment of MTC-related diarrhea. In this small pilot study, improvements in frequency and quality of diarrhea as well as QOL were noted. Further studies in this population are warranted.
authors.affiliation: 1 Department of Endocrine Neoplasia and Hormonal Disorders, The University of Texas MD Anderson Cancer Center , Houston, Texas.
authors.forename: Ramona
authors.initials: R
authors.lastname: Dadu
authors.affiliation: 1 Department of Endocrine Neoplasia and Hormonal Disorders, The University of Texas MD Anderson Cancer Center , Houston, Texas.
authors.forename: Mimi I
authors.initials: MI
authors.lastname: Hu
authors.affiliation: 2 Department of Symptom Research, The University of Texas MD Anderson Cancer Center , Houston, Texas.
authors.forename: Charles
authors.initials: C
authors.lastname: Cleeland
authors.affiliation: 1 Department of Endocrine Neoplasia and Hormonal Disorders, The University of Texas MD Anderson Cancer Center , Houston, Texas.
authors.forename: Naifa L
authors.initials: NL
authors.lastname: Busaidy
authors.affiliation: 1 Department of Endocrine Neoplasia and Hormonal Disorders, The University of Texas MD Anderson Cancer Center , Houston, Texas.
authors.forename: Mouhammed
authors.initials: M
authors.lastname: Habra
authors.affiliation: 1 Department of Endocrine Neoplasia and Hormonal Disorders, The University of Texas MD Anderson Cancer Center , Houston, Texas.
authors.forename: Steven G
authors.initials: SG
authors.lastname: Waguespack
authors.affiliation: 1 Department of Endocrine Neoplasia and Hormonal Disorders, The University of Texas MD Anderson Cancer Center , Houston, Texas.
authors.forename: Steven I
authors.initials: SI
authors.lastname: Sherman
authors.affiliation: 1 Department of Endocrine Neoplasia and Hormonal Disorders, The University of Texas MD Anderson Cancer Center , Houston, Texas.
authors.forename: Anita
authors.initials: A
authors.lastname: Ying
authors.affiliation: 3 Department of Biostatistics, The University of Texas MD Anderson Cancer Center , Houston, Texas.
authors.forename: Patricia
authors.initials: P
authors.lastname: Fox
authors.affiliation: 1 Department of Endocrine Neoplasia and Hormonal Disorders, The University of Texas MD Anderson Cancer Center , Houston, Texas.
authors.forename: Maria E
authors.initials: ME
authors.lastname: Cabanillas
mesh_terms: D000328:Adult; D000368:Aged; D000538:Aluminum Silicates / Q000627:therapeutic use*; D000930:Antidiarrheals / Q000627:therapeutic use*; D018276:Carcinoma, Medullary / Q000150:complications*; D000077215:Clay; D003967:Diarrhea / Q000188:drug therapy* / Q000209:etiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011446:Prospective Studies; D011788:Quality of Life; D013964:Thyroid Neoplasms / Q000150:complications*; D016896:Treatment Outcome
chemical_list: D000538:Aluminum Silicates; D000930:Antidiarrheals; D000077215:Clay