Medical Student Drexel University College of Medicine, US
Introduction: Intractable visceral pain remains a difficult clinical challenge. Treatment options include opiates, nerve or ganglion blocks, intrathecal medication pumps, or ablative procedures, each with particular advantages and disadvantages. Midline myelotomy is a procedure that creates a lesion in the midline ascending nociceptive pathways. We present a case of excellent pain control from a punctate thoracic midline myelotomy in metastatic anal cancer to the penis.
Methods: This case report was conducted through a retrospective EHR chart review.
Results: A 49-year-old-male with a history of opioid use disorder maintained on methadone presented with an anal mass that biopsy revealed to be squamous cell carcinoma. The carcinoma had both local invasion and metastasis to a right internal iliac lymph node and the shaft of the penis. He was treated with chemotherapy and radiation to both the anal mass and the penile shaft. During his treatment, he experienced significant penile and perineal pain refractory to medical management. He experienced minimal transient relief from multiple ganglion impar blocks but still required up to 14,340 oral morphine equivalents per day of hydromorphone with minimal relief. A punctuate midline myelotomy was successfully performed with assistance of intraoperative monitoring to identify the midline and reduce potential complication. The monitoring systems included somatosensory-evoked potentials (SSEPs), “Direct waves” (D-waves), and spinal cord “mapping” via phase reversal technique. The patient reported an over 80% improvement in his pain with a significant reduction in his opiate regimen (792 OME per day, down from 14,330 OME per day) and improvement in his mobility and ambulation. He experienced no other deficits or side effects from the procedure.
Conclusion : Thoracic punctuate midline myelotomy can be a safe and effective therapeutic option for refractory penile or perineal pain.
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