The distribution of chondromas: Why the hand?

Chondroma is a benign hyaline cartilage tumor and is a relatively common skeletal neoplasm. Uneven distribution of this tumor among the various bones and regions of the skeleton is known but no explanation of this phenomenon followed. The current research aimed to document the exact chondroma distribution in the body. We hypothesized that the cases of all subtypes of chondroma have to be investigated in complex and that obtaining combined data from a large cohort of cases may explain the logic of chondroma distribution and may answer the question of why the hand is the main target of the tumor. We retrospectively analyzed 1529 cases of various subtypes of chondroma. Enchondroma was the most frequent type (65.4%) and the hand was the main target location (49.8% of all cases). The right side of the body was affected in 900 cases (58.9%) and in 629 cases (41.1%) the left side was affected (p = 0.03). The general results for tumor distribution are as follows: head and extremities - 92.8%; head, hands, and feet - 71.8%; and hands and feet - 62.8%. In the hand and the feet, multiple chondromas were distributed along the same digital ray in all cases. The anatomical distribution of various subtypes of chondroma follows "the periphery of the being", the uneven lateral distribution, and the "same digital ray" patterns that permits to suggest that genetic mutations affecting the development of the body during the embryonic period are the main etiological component for this tumor.