UTERINE INNERVATION IN ADENOMYOSIS.

MJ QUINN, N KIRK.
Departments of Gynaecology and Histopathology, Hinchingbrooke, Hospital, Huntingdon, Cambridgeshire, UK.

   Objective:  To describe the innervation of the uterus following hysterectomy for adenomyosis.

   Methods:  Retrospective survey of the intrinsic innervation of uteri after hysterectomy in two groups of patients; Group I consisted of fifty two patients with histologically-normal uteri (7/52 were nulliparous; mean age 40 years, range 30-45 years; 45/52 were multiparous; mean age 45.6 years, range 32-54; mean parity 2.0 children, range 1-4 ). Group II consisted of 35 patients with differing degrees of adenomyosis (3/35 were nulliparous, 32/35 were multiparous; mean age 45.6 years, range 32-54 years; mean parity 2.2 children, range 0-4). Eighteen (18/35) had severe adenomyosis extending into the outer third of the myometrium.

Tissue sections, usually taken from the isthmus, were stained with PGP 9.5 (Novocastra Laboratories Ltd, Newcastle upon Tyne, UK) using a standard immunohistochemical regimen. Sections of pancreas were used as positive controls and incubated on all slides throughout the staining procedures. Sections were reviewed by two observers.

   Results:  In group 1, (n=52, normal histological report) normal innervation of the uterine isthmus included concentrations of nerves in the subserosal layer and at the endometrial-myometrial interface with neurovascular bundles distributed throughout the myometrial stroma. There was evidence of chaotic, small-diameter, nerve fibre proliferation throughout the myometrial stroma in 16/45 parous uteri.

In group 2, (n=35 with adenomyosis), in 34/35 uteri there were large areas of uterus without nerves and absence of the endometrial-myometrial nerve plexus. Focal proliferation of small-diameter nerve fibres was observed at the margins of adenomyosis (6/35). Subserosal nerve fibers were still present in those sections that extended to include this region (20/35).

   Conclusion:  Adenomyosis is associated with partial denervation of the myometrium. Focal, assymmetric proliferation of nerve fibers is observed in some cases.