Printed from Australian Family Physician - https://www.racgp.org.au/afp/2014/december/unusual-locations-of-lipoma-differential-diagnosis© The Australian College of General Practitioners www.racgp.org.au

Brown sued, alleging excessive force and violation of his Fourth Amendment rights. He also claimed the officer used the TASER on him a second time, firing the TASER in drive stun mode when Brown was on the ground. Finally, Brown claimed department policies or customs supported these violations. The trial court granted a dismissal on the grounds that Brown failed to allege a violation of clearly established law. Brown appealed.

KEN WALLENTINE is the Chief of the West Jordan (Utah) Police Department and former Chief of Law Enforcement for the Utah Attorney General. He has served over three decades in public safety, is a legal expert and editor of Xiphos, a monthly national criminal procedure newsletter. He is a member of the Board of Directors of the Institute for the Prevention of In-Custody Death and serves as a use of force consultant in state and federal criminal and civil litigation across the nation.

Slipsignlump

Many department policies require that, “A verbal warning of the intended use of the TASER should precede its application, unless it would otherwise endanger the safety of officers or when it is not practicable due to the circumstances” (Lexipol Conducted Energy Device Policy). The warning provides the individual with a reasonable opportunity to voluntarily comply and lets other officers know a TASER may be deployed. Officers are also cautioned to avoid using a TASER where persons whose position or activity is likely to result in a collateral injury (e.g., falls from height, located in water, operating vehicles) (Lexipol Conducted Energy Device Policy). Though the officer may not have intentionally targeted Brown’s head, the recommended TASER target areas include the back, lower center mass and upper legs of the subject. Officers are cautioned to avoid intentionally targeting the head, neck, area of the heart, or genitals (Lexipol Conducted Energy Device Policy).

Slipsigntest

On examination, lipomas are soft compressible masses with normal overlying skin.12 They often display a positive ‘slippage sign’ when the fingers are slid gently over the edge of the tumour.12,19 These tumours are rarely considered in the differential diagnosis of parotid tumours when initial diagnosis is based on clinical findings.6 Before any imaging is performed, the most commonly reported preoperative clinical diagnoses are pleomorphic adenoma and Warthin tumour.20

Jorden Brown was homeless and struggling with addiction. He showed up at the pizza place where his mother worked, hoping for a meal and a place to crash. Instead, Brown’s mother called the police and reported Brown had an outstanding warrant for his arrest. When a responding officer asked Brown for his name, Brown repeatedly provided a false name, even when the officer asked if his last name might be “Brown.”

Slipsignpositive in

The treatment of choice is complete excision after a thorough preoperative clinical and radiological assessment in order to prevent recurrences.1,2 However, complete excision can be difficult, given its infiltrating capacity, and thus, unlike a general lipoma, its resection should include adjacent normal muscular tissues including a portion of the attached muscles.1,26 Although great differences were shown, depending on the investigators, the recurrence rate of intramuscular lipoma is high, reported to be 3–62.5%.22

Slipsignmeaning

Clinically, intramuscular lipomas present as slow-growing diffuse masses, arising from the muscle and giving them a rounded appearance.1 They show the characteristic of becoming soft and flat when surrounding muscles are relaxed; on the other hand, during muscle contraction, they change to a hard round shape, which is of help to differentiate them from other soft-tissue tumours.22,25 Lipomas of the sternocleidomastoid muscle are seldom considered in the preoperative differential diagnosis because of their rarity. According to the previous reports, FNAB with sonography may help in making an early diagnosis of intramuscular lipoma, but the results of FNAB can be supported with CT and confirmed with a histopathological report.1,2

Australian Family Physician was the peer-reviewed, scholarly journal of The Royal Australian College of General Practitioners (RACGP) from 1971 to 2017. From January 2018, it was superseded by AJGP: Australian Journal of General Practice

The extent of surgery should be determined at the time of operation with dual goals of complete mass resection (when possible, with a cuff of normal parotid tissue around the mass) and facial nerve preservation.12 Most clinicians recommend superficial parotidectomy for tumours located within the superficial lobe, with dissection and preservation of the facial nerve and total parotidectomy for deep lobe tumours.12

© The Royal Australian College of General Practitioners 2021. The Royal Australian College of General Practitioners, 100 Wellington Parade, East Melbourne, Victoria 3002, Australia

Preoperative image studies can be particularly useful in identifying the size, location, and even the histological characteristics of lipomatous lesions.7 Ultrasonography can be used as the initial study. The characteristic sonographic appearance is that of an elliptical or rounded mass parallel to the skin surface that is hyperechoic relative to adjacent muscle.8 However, because echogenicity is influenced by the volume of nonfat tissue,9 it may appear as sometimes iso-echoic10 or even hypo-echoic.9 High resolution CT scan imaging can usually be diagnostic even though magnetic resonance imaging (MRI) shows better definition of soft tissue.11 CT shows a well-encapsulated homogeneous mass with few septations and typically low-attenuation with values of –50 to –150 Housefield units.2 MRI presents the typical signal intensity patterns that a black rim is present around the mass clearly defining the borders from the subcutaneous tissue.10,12 Infiltrative margins are not often apparent on CT scanning, but using MRI with fat suppression techniques, this can become more evident.13 Most lipomas pose no diagnostic dilemmas. However, when presented with large (>10 cm) or rapidly growing masses, especially in the head and neck region, physicians should be concerned about malignancy. Among various disease entities of differential diagnosis, the main diagnostic dilemma is to distinguish a lipoma from a well-differentiated liposarcoma.5

Lobulationsignlipoma

SlipsignCyst

The court held the officer was entitled to qualified immunity. And because Brown’s claims against the officer failed, his claims against the chief and the city were also dismissed. The dissenting judge opined that the officer should have been on notice that firing a TASER to the head amounts to a significant physical intrusion requiring a correspondingly significant justification. Brown’s arrest warrant was for the failure to pay a fine. The dissent would not have affirmed the grant of qualified immunity for the officer. Additionally, the dissent disagreed with the majority’s reliance on the audio evidence from the body-worn camera video to bolster the officer’s claim of only a single discharge of the TASER.

The officer asked Brown several times to stay in his car. Nonetheless, Brown got out of the car and began to run; the officer chased him. Without commanding Brown to stop, or providing any verbal warning, the officer quickly fired a TASER device at Brown. One probe struck Brown’s head and the other struck his back. Brown fell to the ground and hit his head.

Intramuscular lipomas can be divided into the well-circumscribed type and the infiltrative type, on the basis of the appearance of the margins in relation to the adjacent muscle fibres. The infiltrative type, which accounts for 83% of intramuscular lipomas is characterised by margins that irregularly invade the surrounding muscle fibres and, in places, completely replace them. The well-circumscribed type, on the other hand, is composed solely of a discrete mass of uniform, mature adipocytes that are clearly delineated from the surrounding muscle.23

Relying on the officer’s body-worn camera recording, the court made short work of Brown’s claim that the officer used the TASER in drive stun mode after Brown was subdued. The body camera video showed the officer energized the TASER just once. “In this context, we don’t need to accept as true any allegation blatantly contradicted by the video.” The court acknowledged TASER devices “make noises in both probe and drive-stun mode,” and that the court heard only the noise associated with a single discharge. “The lack of noise utterly discredits Brown’s claim.”

Fine needle aspiration biopsy (FNAB) is of great value in the diagnostic work-up and the differential diagnosis for parotid mass, but it does not provide sufficient data for diagnosis and its accuracy drops to <50% in the case of lipomatous lesions of the parotid gland.12,20,21

Although most lipomas can be observed without treatment,14 they need excision if there is diagnostic uncertainty, lack of homogeneity to palpation, large neck mass (>10cm), rapid growth, associated pain, deep-seated locations (intramuscular or intermuscular) or cosmetic concern. Treatment is complete surgical excision, but liposuction can be useful in certain locations such as the face.14 Liposuction is sometimes preferred as there is less scarring following the procedure but there is higher chance of recurrence, compared with excision.15,16

Slipsignin lipoma

Lipomas are the most common benign neoplasms of mesenchymal origin and may arise in any location where fat is normally present.1 Lipomas are composed of mature fatty cells and occur predominantly on the upper back, shoulder and abdomen.2,3 In the head and neck region, where only 13% of lipomas are seen,4 the posterior neck space is the most common site, but the anterior neck space is a rare location.4,5 Besides frequent aesthetic consequences, clinical symptoms depend on the size, location and rate of growth of the lesion.5 The most common presentation of lipoma is a painless, well-circumscribed mass with progression in size over time.5 Although the aetiology of lipoma has not been elucidated as yet, heredity, obesity, diabetes, trauma, radiation, endocrine disorder, insulin injection and corticosteroid therapy are occasionally implicated as possible aetiological factors.6 Rarely, lipomas can be associated with syndromes such as hereditary multiple lipomatosis, adiposis dolorosa, Gardner’s syndrome and Madelung’s disease.5

SlipsignMedical

Lipomas are usually located subcutaneously without infiltrating the adjacent tissues. However, intramuscular lipomas are rare benign tumours that account for 1.8% of all lipomas. These tumours of fat tissues are not confined within the subcutaneous fat layer, but infiltrate the skeletal muscles.22

Intramuscular lipomas are usually found on the extremity, but rarely occur in the head and neck region.1 To the best of our knowledge, only four cases of intramuscular lipoma in the sternocleidomastoid muscle have been reported in the literature.1,2,22,24 In addition, because important structures are present densely in small spaces of the head and neck region, it is important to establish a preoperative plan by determining the size and location of the tumour through preoperative clinical and radiologic tests.

The appellate court began by citing other cases in which the court “held that it’s reasonable for officers to tase fleeing suspects.” Thus, the fact that the officer fired a TASER into his back as he ran was not enough to establish excessive force. Brown tried to distinguish his case from precedent by claiming the officer intentionally targeted his head with the TASER probe, but the court disagreed: “We doubt that this difference matters in the context of a mid-chase decision to tase a fleeing suspect. It’s difficult to imagine how a sprinting officer could aim his taser precisely enough to (1) hit a suspect with both taser probes while (2) ensuring that neither probe hits the suspect’s head. It’s even harder to imagine that the Fourth Amendment requires such a feat. That’s precisely why we defer to the ‘split-second’ decisions of officers in fast-paced, complex situations.”

The views expressed by the authors of articles in Australian Family Physician are their own and not necessarily those of the publisher or the editorial staff, and must not be quoted as such. Every care is taken to reproduce articles accurately, but the publisher accepts no responsibility for errors, omissions or inaccuracies contained therein or for the consequences of any action taken by any person as a result of anything contained in this publication. The content of any advertising or promotional material contained within, or mailed with, Australian Family Physician is not necessarily endorsed by the publisher.

Although adipose tissue is normally present in the parotid gland, intraglandular lipomas of the parotid gland are rare benign lesions that occur in about 1% of all parotid tumour cases.12,17 The typical history of patients with intraglandular lipoma is that of a slowly growing, painless mass over the parotid area, the unilateral swelling of the parotid gland.12 They might be associated with ductal obstruction leading to sialadenitis, depending on the type of lipoma present.18