{'fraction_non_alphanumeric': 0.013333333333333334, 'fraction_numerical': 0.008888888888888889, 'mean_word_length': 5.48559670781893, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Preliminary proposal for surgical classification of sacral tumors.

OBJECT
The authors propose a new surgical classification method for sacral tumors that improves the guidance for specific surgical decisions and approaches.


METHODS
The authors retrospectively studied the clinical courses of 92 patients with sacral tumors treated at the Changhai Hospital; all patients underwent tumor resection between January 2000 and August 2005. The clinical characteristics, imaging features, and pathological classifications were carefully assessed in each case. The tumors were classified according to the imaging features and intraoperative findings. The surgical approach and the resection area were determined according to the tumor classification.


RESULTS
The proposed surgical classification system divided the sacral tumors into 2 major types according to the lesion's anatomical position in the sagittal plane. The tumors were further divided into 4 subtypes according to the length of the tumor's anterior protrusion into the pelvic cavity. Finally, each tumor subtype was classified into 16 areas according to the anatomical position in the cross-sectional plane. This classification method was used to categorize the sacral tumors, all of which were totally resected under the naked eye. Postoperatively symptoms were improved to varying degrees.


CONCLUSIONS
The appropriate classification of sacral tumors and the selection of a corresponding surgical approach can improve the rate of total resection and the surgical safety, as well as decrease the recurrence rate.