Neck masses in children — branching viva

Opening

Examiner: A 4-year-old is brought in with a three-week history of a small, soft, tender lump under the angle of the jaw, just after a cold. How do you approach this, and what is your differential? [2]

Candidate: This is most likely a reactive viral lymph node, which is the commonest cause of cervical lymphadenopathy in children — cervical nodes are palpable in up to ninety per cent of children aged four to eight years. The features that support a benign reactive node are the preceding viral illness, the tender, soft, mobile character, the submandibular or anterior-triangle location, and the short three-week history. My approach is to take a focused history for red flags (weight loss, night sweats, fever, tuberculosis or animal contact) and examine the node's size, consistency, fixation and the other node groups. If it is a straightforward reactive node in a well child, I would reassure the family and give a clear safety-net to return at four to six weeks if the node has not resolved, or earlier if it enlarges or the child becomes unwell. [2] [1]

Branch 1 — the congenital midline mass

Examiner: A different child: a 6-year-old with a painless midline lump at the level of the hyoid that the mother says moves when the child swallows. What is this, and how do you confirm it at the bedside? [3]

Candidate: This is most likely a thyroglossal duct cyst, the commonest congenital midline neck mass. It arises from a remnant of the thyroglossal duct, the tract along which the thyroid descends from the foramen caecum to its pretracheal position, and because that tract passes through the hyoid bone the cyst moves upward when the child protrudes the tongue and when the child swallows. That is the bedside manoeuvre that distinguishes it from a dermoid cyst (which is more superficial and does not move) or a thyroid nodule (which moves only with swallowing). I would request an ultrasound to confirm the cystic lesion and to locate a normally positioned thyroid gland, and check thyroid function tests, because the cyst can rarely contain the only functioning thyroid tissue. [3]

Examiner (probe): How do you manage it definitively, and why not simply enucleate the cyst? [3]

Candidate: The definitive management is the Sistrunk procedure — excision of the cyst together with the central portion of the hyoid bone and the tract up to the foramen caecum — performed electively once any infection has settled. Simple enucleation of the cyst leaves residual tract behind, and that residual tract epithelium is the main cause of recurrence, so the Sistrunk procedure is the standard of care. [3]

Branch 2 — the mycobacterial node

Examiner: Now a 3-year-old, otherwise well, with a six-week painless node in the right anterior triangle with faint violet-grey overlying skin. What is your concern, and what must you not do? [4]

Candidate: This is the classic picture of non-tuberculous mycobacterial (NTM) cervicofacial lymphadenitis — a chronic, unilateral, painless, enlarging node with the characteristic violet-grey skin discolouration in an otherwise well child aged one to five years. The critical thing I must not do is incise and drain it under the impression it is a pyogenic abscess, because in NTM disease incision and drainage creates a chronic discharging sinus and makes subsequent management far harder. The definitive treatment, as set out by the International Pediatric Otolaryngology Group consensus, is complete surgical excision, so I would refer to paediatric otolaryngology. I would request an ultrasound first and distinguish it from tuberculous lymphadenitis with a tuberculin test or interferon-gamma release assay and a chest radiograph. [4]

Branch 3 — the red-flag node

Examiner (probe): Now a 15-year-old with a six-week painless, firm, fixed node in the left supraclavicular fossa, night sweats and weight loss. How does your approach change? [5]

Candidate: This is a red-flag node and my approach changes completely from reassure-and-safety-net to urgent investigation and paediatric oncology referral. A node in the supraclavicular fossa is pathologic until proven otherwise because those nodes drain the thorax, abdomen and pelvis, so the concern is lymphoma or metastatic disease; combined with the constitutional B symptoms, this is lymphoma until excluded. I would arrange an ultrasound, then a tissue biopsy — a core biopsy, or preferably an excisional biopsy of an intact node for histology, flow cytometry and molecular studies, since lymphoma subtyping needs intact architecture. I would take a full blood count, film, LDH and inflammatory markers and an early chest radiograph for a mediastinal mass, and refer urgently to paediatric oncology for staging and protocol therapy. I would not give empirical antibiotics or steroids before the biopsy, because steroids can obscure the histology. [5] [2]

Examiner (probe): What if someone had prescribed two courses of antibiotics and the node had not changed? [2]

Candidate: That itself is a red flag. A node that fails to respond to a course of antibiotics, or that persists or grows beyond four to six weeks, must be investigated with ultrasound and tissue sampling rather than treated empirically a third time — benign reactive nodes resolve. Re-prescribing antibiotics for a persistent, enlarging, firm or supraclavicular node is the classic pitfall that delays the diagnosis of lymphoma. [2]

Close

Examiner: Summarise your safe approach to the paediatric neck mass in one line. [1]

Candidate: Classify the mass by location and behaviour at the bedside — midline versus lateral, anterior versus posterior triangle, supraclavicular, tender versus painless, growing versus stable — reassure and safety-net the straightforward reactive node, ultrasound the rest, biopsy and refer urgently to paediatric oncology the node that is persistent, firm, fixed, supraclavicular, posterior-triangle, or accompanied by B symptoms, and never drain a suspected non-tuberculous mycobacterial node. [1] [2] [4]