Nerve Root Sparing En Bloc Resection of Sacral Chondrosarcoma: Technical Note and Review of the Literature

BACKGROUND

Total en bloc sacrectomy provides the best long-term local control for large primary bony sacral tumors, but often requires lumbosacral nerve root sacrifice leading to loss of ambulation and/or bowel, bladder, and/or sexual dysfunction. Nerve-sparing techniques may be an option for some patients that avoid these outcomes and accordingly improve postoperative quality of life.

OBJECTIVE

To describe the technique for a posterior-only en bloc hemisacrectomy with maximal nerve root preservation and to summarize the available literature.

METHODS

A 38-yr-old woman with a 7.7 × 5.4 × 4.5 cm biopsy-proven grade 2 chondrosarcoma involving the left L5-S2 posterior elements underwent a posterior-only left hemisacrectomy tri-rod L3-pelvis fusion. A systematic review of the English literature was also conducted to identify other descriptions of high sacrectomy with distal sacral nerve root preservation.

RESULTS

Computer-aided navigation facilitated an extracapsular resection that allowed preservation of the left-sided L5 and S3-Co roots. Negative margins were achieved and postoperatively the patient retained ambulation and good bowel/bladder function. Imaging at 9-mo follow-up showed no evidence of recurrence. The systematic review identified 4 prior publications describing 6 total patients who underwent nerve-sparing sacral resection. Enneking-appropriate resection was only obtained in 1 case though.

CONCLUSION

Here we describe a technique for distal sacral nerve root preservation during en bloc hemisacrectomy for a primary sacral tumor. Few prior descriptions exist, and the present technique may help to reduce the neurological morbidity of sacral tumor surgery.

Anal duplication: is surgery indicated? A report of three cases and review of the literature

AIM OF THE STUDY

Anal canal duplications (ACDs) are extremely rare with only approximately 90 cases described in the literature. We report on three additional patients.

METHODS

Cases were analyzed to evaluate presenting symptoms, physical exam and MRI findings. A comprehensive literature review was performed to compare our patients to previously described cases. IRB approval was obtained for this study (19-0394).

MAIN RESULTS

The first female patient presented with an asymptomatic ACD at 2 years old. The second patient was a 13-year-old female with perianal drainage that was initially mistaken for a fistula-in-ano and ultimately found to have an ACD associated with a dermoid cyst. Both posterior midline duplications shared a common wall with the rectum, but did not communicate with it. The ACDs and dermoid cyst were successfully excised through a posterior sagittal approach with no postoperative complications. Histology demonstrated the presence of both squamous epithelium and transitional anal epithelium in each case. The third patient was 8 months old and had a tethered cord, hemisacrum, presacral mass, and anal duplication that was initially undiagnosed. These results corroborate patterns identified in other reports of ACDs with over 90% being female and in the posterior midline. The majority are asymptomatic, but may present with symptoms of local or even systemic infection.

CONCLUSION

An opening in the midline posterior to the anus should raise clinical suspicion for anal canal duplication. An associated presacral mass must be ruled out. Complete excision through a posterior sagittal approach is recommended upon diagnosis to avoid symptomatic presentations. The key part of the operation is the separation of the ACD from the posterior rectal wall.