Decrease of serum carnitine levels in patients with or without gastrointestinal cancer cachexia.
OBJECTIVE
To evaluate the levels of serum carnitine in patients with cancer in digestive organs and to compare them with other cancers in order to provide new insights into the mechanisms of cachexia.


METHODS
Fifty-five cachectic patients with or without gastrointestinal cancer were enrolled in the present study. They underwent routine laboratory investigations, including examination of the levels of various forms of carnitine present in serum (i.e., long-chain acylcarnitine, short-chain acylcarnitine, free carnitine, and total carnitine). These values were compared with those found in 60 cancer patients in good nutritional status as well as with those of 30 healthy control subjects.


RESULTS
When the cachectic patients with gastro-intestinal cancer were compared with the cachectic patients without gastrointestinal cancer, the difference was -6.8 micromol/L in free carnitine (P < 0.005), 0.04 micromol/L in long chain acylcarnitine (P < 0.05), 8.7 micromol/L in total carnitine (P < 0.001). In the cachectic patients with or without gastrointestinal cancer, the difference was 12.2 micromol/L in free carnitine (P < 0.001), 4.60 micromol/L in short chain acylcarnitine (P < 0.001), and 0.60 micromol /L in long-chain acylcarnitine (P < 0.005) and 17.4 micromol/L in total carnitine (P < 0.001). In the cachectic patients with gastrointestinal cancer and the healthy control subjects, the difference was 15.5 micromol/L in free carnitine (P < 0.001), 5.2 micromol /L in short-chain acylcarnitine (P < 0.001), 1.0 micromol/L in long chain acylcarnitine (P < 0.001), and 21.8 micromol/L in total carnitine (P < 0.001).


CONCLUSIONS
Low serum levels of carnitine in terminal neoplastic patients are decreased greatly due to the decreased dietary intake and impaired endogenous synthesis of this substance. These low serum carnitine levels also contribute to the progression of cachexia in cancer patients.
Malaguarnera
Mariano
M
Department of Senescence, Urological and Neurological Sciences, University of Catania, Cannizzaro Hospital, Catania, Italy. malaguar@unict.it.
Risino
Corrado
C
Gargante
Maria Pia
MP
Oreste
Giovanni
G
Barone
Gloria
G
Tomasello
Anna Veronica
AV
Costanzo
Mario
M
Cannizzaro
Matteo Angelo
MA
D000328:Adult; D001943:Breast Neoplasms / Q000097:blood; D002100:Cachexia / Q000097:blood* / Q000209:etiology* / Q000503:physiopathology; D002331:Carnitine / Q000097:blood*; D016022:Case-Control Studies; D004032:Diet; D018450:Disease Progression; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000097:blood* / Q000150:complications* / Q000503:physiopathology; D006801:Humans; D007680:Kidney Neoplasms / Q000097:blood; D008175:Lung Neoplasms / Q000097:blood; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000097:blood; D012878:Skin Neoplasms / Q000097:blood
D002331:Carnitine