<h4>Background</h4>Because of its accuracy and cost-effectiveness, thyroid fine needle biopsy (FNB) is the procedure of choice in the preoperative management of thyroid nodules. Needle tract seeding (NTS) has been a concern since the earliest days of FNB, contributing to the delayed acceptance of FNB as a safe procedure. In this review we tried to systematically record all reports of NTS after diagnostic thyroid FNB and provide useful hints to minimize the risk of NTS.<h4>Methods</h4>Computerized advanced search for primary evidence was performed in the PubMed (Public/Publisher Medline) electronic database. The search was not limited by publication time or English language.<h4>Results</h4>Ten relevant articles were found: eight case reports, one case in a surgical series, and one retrospective observational study.<h4>Conclusions</h4>Despite initial concerns about the risk of NTS, FNB is now considered to be a safe procedure. Although proper FNB technique can reduce its risk, NTS is an unavoidable complication of FNB, which clinicians should be aware of. However, the incidence of NTS is low and it doesn't seem to affect the prognosis because the seedings can be surgically removed without recurrence. The management of the thyroid nodules is to-date based on FNB, and the benefits from FNB (elimination of needless imaging and surgery) far outweigh the potential risk for NTS.

Simple Summary Many women fear that breast needle biopsies increase the risk of cancer spread due to tumor cell displacement. Although evidence suggests minimal impact on breast cancer loco-regional recurrence or distant metastasis, technical modifications of needle biopsy procedures, including the use of cryoablation, can reduce the potential risks of breast needle-biopsy-induced cancer cell displacement to reduce patient fears of breast needle biopsy procedures. Abstract Purpose: Many women fear that breast needle biopsies increase the risk of cancer spread. The purpose of this review article is to discuss the breast cancer literature regarding the risk of needle-biopsy-induced cancer cell displacement and its impact on local and regional recurrence and breast cancer survival. Methods: A literature review is performed to discuss the risks and mitigation of needle-biopsy-induced cancer cell displacement. Results: Needle-biopsy-induced cancer cell displacement is a common event. The risk is influenced by the biopsy technique and the breast cancer type. Evidence suggests that the risk of needle-biopsy-induced cancer cell displacement may potentially increase the odds of local recurrence but has no impact on regional recurrence and long-term survival. Conclusions: Technical modifications of needle biopsy procedures can reduce the risk of breast needle-biopsy-induced cancer cell displacement and potentially reduce the risk of local recurrence, especially in patients for whom whole breast radiation is to be omitted. Abstract Simple Summary Many women fear that breast needle biopsies increase the risk of cancer spread due to tumor cell displacement. Although evidence suggests minimal impact on breast cancer loco-regional recurrence or distant metastasis, technical modifications of needle biopsy procedures, including the use of cryoablation, can reduce the potential risks of breast needle-biopsy-induced cancer cell displacement to reduce patient fears of breast needle biopsy procedures. Abstract Purpose: Many women fear that breast needle biopsies increase the risk of cancer spread. Despite the importance of diagnostic needle biopsy in the management of breast cancer, many patients are reluctant to undergo the procedure for fear that penetration of the tumor with a biopsy needle might itself cause the cancer to spread—a concern which leads some patients to defer needle biopsy procedures for weeks of months. On the other hand, there is compelling evidence that a ≥3-month delay between abnormal imaging and a positive needle biopsy may lead to a 20% relative reduction in overall survival [ 10 ]. Thus, ironically, delays in performing a diagnostic needle biopsy can directly increase the risk of cancer cell spread and death among the very women who most fear a diagnostic needle biopsy. Patient concerns about the potential for cancer cell dissemination appear to be partly justified. Indeed, a large body of data show needle tract seeding to be a relatively common event after a breast diagnostic needle biopsy, and the The primary role of epinephrine in the local anesthetic mixture is to cause the vasoconstriction of nearby arteries and veins to restrict blood flow into and out of the area, extend the duration of the pain-relieving anesthetic, and theoretically decrease the potential for the dissemination of cancer cells into the bloodstream [ 24 , 25 ]. These effects last up to 6 h. Use of a coaxial or introducer. A coaxial or introducer is a large-diameter needle that can be inserted into the breast through which a small-diameter biopsy needle can be inserted to obtain one or more biopsy samples. Ultrasound-guided or palpation-guided fine needle aspiration (FNA) utilizes a small needle to collect individual or clusters of cells. In general, FNA is performed with a 21–27-gauge needle, a fraction of the diameter of biopsy devices that are typically used for a core needle biopsy (CNB). By collecting a smaller sample of cells, FNA reduces disruption of the tumor mass, decreases bleeding, and potentially lowers the risk of cancer spread. While FNA has its advantages, several limitations are noteworthy. However, leaving the biopsy needle and specimen within the mass until the very end of the mass cryoablation could compromise specimen histology such that it might be unsuitable for histological assessment [ 30 ]. 3. Discussion Although most breast needle biopsies yield a benign diagnosis, there is substantial concern amongst the public that traumatic penetration of cancer with a needle biopsy device causes the shedding of cancer cells into the needle tract or bloodstream, which may increase the risk of local recurrence or distant metastasis. As a result, some patients with suspicious breast abnormalities are reluctant to undergo a diagnostic needle biopsy. In reality, invasive cancers develop the ability to spread from the moment they become vascularized (~2 mm), which is typically years before they reach the average dimension (14 mm) typically detected by annual mammograms [ 23 , 31 ]. As a result, 3–6% of women diagnosed with breast cancer today are found to have de novo stage IV disease, meaning that clinically detectable distant metastasis had already been established well before the diagnostic needle biopsy was performed [ 32 ]. Furthermore, positive axillary nodes are detected in up to 27% of patients with breast cancers 2 cm or smaller, in up to 62% of patients with breast cancers between 2 cm and 5 cm, and in up to 78% of patients with breast cancers >5 cm, indicating that disease has already been established in the lymph nodes before any needle biopsies have been performed [ 11 ]. Considering that most cancers exhibit growth and possible spread months or years before they are detected by mammography, ultrasound, breast MRI, or examination, there is sufficient reason to doubt the significance of a single needle biopsy event to a patient’s risk of local recurrence or death.

BACKGROUND/OBJECTIVE The occurrence of iatrogenic tumor cell seeding (seeding) in needle tract scars formed by core needle biopsy (CNB) or vacuum-assisted biopsy (VAB) is well known. Some risk factors for seeding have been reported, but the clinicopathological risk factors and its prognosis have not been fully investigated. We evaluated the clinical features and prognosis of seeding. METHODS We included 4405 patients who had undergone surgery (lumpectomy or mastectomy) with a diagnosis of breast cancer by preoperative CNB or VAB at our hospital between January 2012 and February 2021. Data of patients with confirmed presence of seeding in resected specimens were collected from pathological records. We analyzed the risk factors of seeding using logistic regression analysis and compared the ipsilateral breast tumor recurrence (IBTR) rate between cases based on the presence or absence of seeding in the lumpectomy group. RESULTS Of the 4405 patients, 133 (3.0%) had confirmed seeding. Univariate analysis revealed the association of clinicopathological features of seeding with lower nuclear grade (NG1 vs NG2-3; p = 0.043), lower Ki-67 (<30 vs. ≥30; p = 0.049), estrogen receptor (ER) positivity (positive vs negative; p<0.01), and human epidermal growth factor receptor 2 (HER2) negativity (negative vs positive; p = 0.016). Multivariate analysis showed ER positivity (odds ratio, 5.23; p<0.05) as an independent risk factor of seeding. The IBTR rate was not significantly different between the seeding and non-seeding groups. CONCLUSIONS Seeding was more likely to occur in ER positive, HER2 negative carcinomas with less aggressive features, and may remain subclinical if adequate adjuvant treatments are administered.