Anaplastic thyroid carcinoma implantation after fine needle aspiration cytology

Abstract

We report the case of a 59-year-old man with a two-month history of a fast-growing, left-sided neck mass and a 5 mm nodule over a thyroid mass at the site of fine needle aspiration cytology performed four weeks earlier. Histopathological studies confirmed anaplastic carcinoma of the thyroid and cutaneous needle track seeding of the primary tumour. The patient succumbed to extensive disease 10 weeks after initial diagnosis. To our knowledge, this is a rare report of implantation of anaplastic thyroid carcinoma along the track of fine needle aspiration. Some factors involved in needle track seeding are: needle size; number of passes; withdrawing the needle without releasing suction; injecting the tumour at time of biopsy; and inherent characteristics of the lesion (e.g. number of cells dislodged, adhesiveness of cells, amount of stroma present, enzymes released and immunologic characteristics).

Primary cell cultures from anaplastic thyroid cancer obtained by fine‐needle aspiration used for chemosensitivity tests

“…An anecdotal report of cutaneous needle track seeding after FNA in a patient with ATC has recently been published 31 . In our patients we were unable to find any sign of needle track seeding after FNA, confirming that FNA in ATC is a reliable and safe procedure.…”

Clinical complications following thyroid fine‐needle biopsy: a systematic review

“…Although spontaneous cutaneous or muscular metastasis of thyroid carcinomas cannot be excluded, implantation is more likely. Indications of needle track seeding rather than metastasis are: (i) recurrence at the site of FNB (described in all the above cases); (ii) linear arrangement of the skin and/or muscular seeding(s) and thyroid nodule; 21,40–42,62 (iii) implanted tumour location away from the surgical incision; 41,42,62 (iv) absence of capsular or vascular invasion or nodal/distant metastasis; 39,42,62,63 (v) existence of scar tissue surrounding the implant; 39 (vi) absence of lymphoid or neurovascular tissue (which rules out the possibility of lymphatic metastasis or perineural invasion); and 21,62 (vii) a central haemorrhagic papule on the implanted lesion, suggestive of a previous needle injury 43 …”

“…3-5 days before FNB 26,27 Small needle size (25-27G) especially for markedly hypervascular nodules or re-aspiration 28,29 FNC instead of FNA in nodules close to large vessels 30 US guidance, especially in nodules close to large vessels 5,30 Slight stretching of the skin above the nodule 9 Firm pressure to the biopsy site with a sterile gauze pad for 2-3 min after FNB (longer in bleeding diathesis) 1,3,8,28 In case of an increasing haematoma that cannot be stopped by pressure, patients should be advised to report to the emergency department (massive haematomas may occur hours after FNB) 8 In cases of hyperthyroidism or thyroiditis De Quervain's FNB should be delayed until euthyroidism restoration 31,32 In cases of complex nodules, direct biopsy (US-FNB) of the solid part without previous evacuation of the fluid 17 Avoidance of repeat FNB shortly after the initial one 33,34 Acute transient swelling ‡ (1/1) Delayed transient swelling ‡ (1/1) Infection (2/3) Alcohol cleansing and iodine skin prep at biopsy site before FNB 28 Adequate sterile conditions during FNB 35,36 Antibiotics in immunosuppressed patients after FNB (prophylactically) 37 Sterile gel in US-FNB Recurrent laryngeal nerve palsy (0·036-0·9%/2) Small needle size 38 Not penetrating the dorsal site of the nodule 19 Vasovagal reaction (0·5-1·3%/1) Pain Suction release before needle withdrawal or use of non-aspiration technique (FNC) 3,17,28,[39][40][41][42][43] Avoidance an excessive piston-like motion of the needle 21 Avoidance of multiple passes and repeat FNB, if possible 3,28 Needle track sinu...…”

“…61 Implantation may be facilitated in cases of immunodeficiency or untreated carcinomas. 61 Post-FNB cutaneous or muscular implantation have been described in papillary, 20,21,[39][40][41]62 follicular 42,61,63 and anaplastic carcinoma, 43 but not in medullary carcinoma, thyroid lymphoma, other primary thyroid malignancy or metastatic carcinoma. Interestingly, in all the above cases, a 23-G or larger needle was used.…”

“…Indications of needle track seeding rather than metastasis are: (i) recurrence at the site of FNB (described in all the above cases); (ii) linear arrangement of the skin and/or muscular seeding(s) and thyroid nodule; 21,[40][41][42]62 (iii) implanted tumour location away from the surgical incision; 41,42,62 (iv) absence of capsular or vascular invasion or nodal/distant metastasis; 39,42,62,63 (v) existence of scar tissue surrounding the implant; 39 (vi) absence of lymphoid or neurovascular tissue (which rules out the possibility of lymphatic metastasis or perineural invasion); and 21,62 (vii) a central haemorrhagic papule on the implanted lesion, suggestive of a previous needle injury. 43 There is no evidence that needle track seeding affects long-term survival in patients with thyroid carcinoma. Since survival is not affected in patients with more aggressive tumours, such as breast and renal adenocarcinoma, the same could be assumed for thyroid carcinoma.…”