A 38-year-old woman is 3 weeks post-open appendectomy. She presents with a painless, firm, nodular mass at the surgical scar measuring 2 × 1.5 cm, with no erythema, drainage, or systemic symptoms. The mass has been growing slowly since week 2 postoperatively. What is the most appropriate next step in management?

Explanation

## Clinical Presentation Analysis This patient presents with a **firm, nodular, slowly growing mass** at a surgical scar 3 weeks post-appendectomy. While hypertrophic scars and keloids are common wound healing complications, the clinical description here raises concern for a **desmoid tumor (aggressive fibromatosis)** or other soft tissue neoplasm, which must be excluded before initiating scar-directed therapy. **Key Point:** A firm, nodular, progressively growing mass at a surgical scar is NOT a classic presentation of a hypertrophic scar or keloid alone. Desmoid tumors are well-known to arise at surgical sites (post-laparotomy/appendectomy), and their management differs fundamentally from benign scar tissue. ## Why Imaging Is the Best Next Step Before committing to any intervention — whether steroid injection, observation, or excision — the lesion must be **characterized**: | Feature | Hypertrophic Scar / Keloid | Desmoid Tumor | |---|---|---| | **Onset** | 2–4 weeks post-injury | Weeks to months post-surgery | | **Texture** | Firm, raised, within/near scar | Firm, nodular, deep to skin | | **Growth** | May plateau or regress | Progressively enlarges | | **Imaging** | Not required | MRI is gold standard | | **Treatment** | Steroids, silicone, pressure | Surgery ± adjuvant therapy | | **Histology** | Fibroblasts within dermis | Spindle cells, infiltrative pattern | **Ultrasound** can rapidly assess depth, vascularity, and tissue characteristics. **MRI** is the gold standard for soft tissue masses, delineating margins, depth, and relationship to adjacent structures — critical for surgical planning if needed. **High-Yield:** The "best next step" principle in surgery dictates that an uncharacterized, growing soft tissue mass requires imaging before intervention. Injecting steroids into an undiagnosed lesion (e.g., a desmoid or low-grade sarcoma) would be inappropriate and potentially harmful. ## Why Other Options Are Suboptimal **Immediate excision (Option A):** While excision with histopathology is ultimately appropriate if imaging suggests a neoplasm, proceeding directly to excision without imaging is suboptimal — imaging guides surgical planning (margins, depth, involvement of adjacent structures) and avoids unnecessary surgery if the lesion is benign. **Observation alone (Option B):** Watchful waiting for 4–6 weeks is inappropriate for a progressively growing nodular mass. Delaying workup risks missing a desmoid tumor or sarcoma at an earlier, more resectable stage. **Intralesional triamcinolone (Option C):** Steroid injection is appropriate for a confirmed hypertrophic scar or keloid, but administering it to an uncharacterized mass is premature and potentially dangerous. Injecting a desmoid tumor or sarcoma with steroids delays diagnosis and may alter tissue architecture, complicating subsequent histopathology. ## Clinical Pearl > Desmoid tumors (aggressive fibromatosis) are locally invasive, non-metastasizing soft tissue tumors that classically arise at sites of prior trauma or surgery. They are associated with FAP/Gardner syndrome. MRI is the investigation of choice. Management includes wide local excision, with adjuvant radiotherapy for positive margins. [cite: Sabiston Textbook of Surgery 21e Ch 6 & Ch 31; Harrison's Principles of Internal Medicine 21e; Grabb & Smith's Plastic Surgery 7e Ch 3]