Wide Trichoblastoma Resection and Local Advancement Flap Reconstruction

March 09, 2025  /  Julius Liptak

Signalment: 10-year-old, FS Labrador retriever

History:

Suspected local tumor recurrence following incomplete histologic excision of a benign trichoblastoma dorsal to the left upper eyelid.

Physical exam findings:

  • 31.7 mm x 39.1 mm pedunculated and ulcerated cutaneous mass arising from the dorsal aspect of the left upper eyelid

  • Left corneal opacity, stained negative

Diagnostic and clinical staging tests:

  • CBC: mild anemia

  • Serum biochemistry: no abnormalities

  • Fine-needle aspirate: suspected trichoblastoma

Notes:

While I thought that this was most likely a local recurrence based on the history and location of this mass, we did also discuss the possibility of a malignant tumor because it is rare to see local tumor recurrence of a benign tumor, even following incomplete histologic excision, and the time interval since the first surgery (2 months), growth rate of the tumor, and appearance of the tumor (ulcerated) were all more consistent with a more aggressively behaving tumor.

Treatment:

Wide surgical resection with 2 cm lateral margins and temporal muscle fascia for deep margins, followed by reconstruction using a local advancement flap. The surgical defect could have been closed primarily but this would have resulted in distortion of the upper eyelid and possibly contributed to worsening keratitis. The advancement flap was advanced parallel to the eyelid to avoid distortion of the eyelid and maintain eyelid function.

Outcome:

  • Benign trichoblastoma with complete histologic excision (narrowest lateral margins 13.0 mm)

  • Mild surgical site infection, resolved with culture-directed antibiotics

Video link: https://www.youtube.com/watch?v=BhMrMKSpLtI&t=1506s

Tags: #trichoblastoma #reconstruction #advancementflap

Appearance of the suspected locally recurrent trichoblastoma immediately before surgery.

The mass was resected with 2 cm lateral margins and temporal muscle fascia (pictured) for deep margins.

The defect following wide resection of the mass. This could have been closed primarily, but this would have resulted in the upper eyelid being pulled dorsally and possibly preventing full closure of the eyelid, thus predisposing to keratonjunctivitis sicca and corneal ulceration. As a result, we planned on reconstructing this defect with a local advancement flap from the lateral face, parallel to the upper eyelid.

The width of the advancement flap is equal to the width of the defect, and the length was extended so that the flap could be advanced into the defect with minimal tension.

The advancement flap was undermined, preserving the subdermal plexus. This is a random pattern or subdermal plexus flap and the blood supply to the flap is dependent on preservation of the subdermal plexus.

The local flap was advanced into the defect.

Tag sutures were used on the corners of the advancement flap to maintain alignment of the flap while suturing it in place.

The advancement flap was secured in two layers, a subcutaneous layer using 3-0 Monocryl in a simple continuous suture pattern.

The advancement flap was secured in two layers, with skin sutures in the external layer consisting of 3-0 Nylon cruciate sutures on the leading edge of the advancement flap where there was the greatest potential for tension, and continuous Ford interlocking suture patterns along the rostral and caudal aspects of the flap where there was minimal tension.

The dog did have a surgical site infection and this quickly resolved following treatment with culture-directed antibiotics. This is the appearance of the advancement flap at suture removal 14 days postoperatively.

The dog did have a surgical site infection and this quickly resolved following treatment with culture-directed antibiotics. This is the appearance of the advancement flap at suture removal 14 days postoperatively.