REVIEW OF TEMPORAL BONE MALIGNANCY WITH CRITICAL temporal bone malignancy. Following this, regression

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    Jaspreet et al. World Journal of Pharmaceutical and Medical Research

    108

    REVIEW OF TEMPORAL BONE MALIGNANCY WITH CRITICAL APPRAISAL OF

    LONG-TERM OUTCOMES FOR SURGICAL MANAGEMENT: SYSTEMATIC REVIEW

    AND META-ANALYSIS

    Dr. Jaspreet Singh Badwal* 1 and Mrinal Deka

    2

    1 Head and Neck Surgeon (FUICC, Netherlands Cancer Institute), Independent Research in Association with

    Department of Statistics, Assam University, Silchar, Assam, India. 2 PhD Research Scholar at Department of Statistics, Assam University, Silchar, Assam, India.

    Article Received on 15/06/2019 Article Revised on 05/07/2019 Article Accepted on 26/07/2019

    INTRODUCTION

    As is truth from lie and facts from fallacy, it is hard to

    distinguish the uncommon from the not so uncommon. If

    to speak of temporal bone malignancies, the incidence

    reported may be extremely low, only until one

    encounters an obvious presentation, when least

    expecting. As they say “chance favours the prepared

    mind”, the surgeon behold watchful, lest the diagnosis

    would be missed, only to end as the most ominous

    consequences for an innocent patient. The incidence

    reported for temporal bone malignancies is between 1

    and 6 per million, such that cancers of external auditory

    canal and temporal bone comprise less than 0.2% of all

    head and neck cancers. [1-3]

    The demographics are well

    reported with a typical male to female ratio of 2:1 and up

    to 20% cases affecting the pediatric age group. The

    overall age is in the range of 40-75 years. [4-8]

    60-80% of

    the malignancies are identified as squamous cell

    carcinomas, while 20% are adenoid cystic carcinomas or

    adenocarcinomas. Primary basal cell carcinomas of

    temporal bone occur seldom, while melanomas are even

    more rare. [4]

    Majority of tumours in adult age group are

    squamous cell carcinomas, while most in pediatric age

    group are rhabdomyosarcomas, thus exhibiting a bimodal

    distribution of tumour incidence.

    wjpmr, 2019,5(8), 108-129

    SJIF Impact Factor: 4.639

    Review Article

    ISSN 2455-3301

    WJPMR

    WORLD JOURNAL OF PHARMACEUTICAL

    AND MEDICAL RESEARCH www.wjpmr.com

    *Corresponding Author: Dr. Jaspreet Singh Badwal

    Head and Neck Surgeon (FUICC, Netherlands Cancer Institute), Independent Research in association with Department of Statistics, Assam

    University, Silchar, Assam, India.

    ABSTRACT

    Purpose: The purpose of the study is to investigate the trends in long term outcomes for surgical treatment of

    temporal bone malignancy and generate guidelines for future benchmark reference, in order to establish a treatment

    pathway for critical decision making, supported by cumulative evidence gathered over decades of research. Apart

    from this, the study will aim to answer four key questions in relation to temporal bone malignancy: (1) Has

    survival for temporal bone malignancy improved over the last few decades (2) Is Total temporal bone resection

    ever indicated ? (3) How does prognosis change when structures such as the dura mater, brain and internal carotid

    artery become involved ? What is the feasibility of surgery in these instances ? (4) What is the role of postoperative

    radiation therapy ? Materials and Methods: A systematic review was conducted to study the long term outcomes

    of surgical management of temporal bone malignancy. 736 articles had been published till October 2018, which

    included retrospective studies, prospective studies, SEER Database surveys, Multicenter studies and smaller

    descriptive studies. References of the selected studies were further searched for relevant articles. Apart from this, a

    search was conducted over Google Scholar to obtain related articles. Subsequently, a meta-analysis was completed

    to extrapolate the cumulative survival, hazard rate, survival probability and event rate for surgical management of

    temporal bone malignancy. Following this, regression analysis was conducted to study the outcomes of primary

    surgery +/- adjuvant radiotherapy as a treatment protocol for temporal bone malignancy. Results: The long term

    outcomes for surgical management of temporal bone malignancy have improved over the last few decades. Also,

    outcomes for surgical management of advanced stage disease show a favourable trend. Further clinical trials and

    multicentre studies should be carried out to strengthen the results for this separate clinical cohort. Primary surgery

    +/- adjuvant radiotherapy has commendable long term clinical outcomes in the contemporary skull base era.

    Conclusion: Long term outcomes for surgical management of temporal bone malignancy show slow but persistent

    improvements resulting from the parallel consistent development of skull base surgical techniques.

    KEYWORDS: Temporal bone carcinoma; outcomes; survival; surgical management; primary surgery; temporal

    bone malignancy; carcinoma external auditory canal; middle ear cancer; treatment temporal bone carcinoma; long

    term outcomes; survival outcomes; lateral skull base malignancy.

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    Jaspreet et al. World Journal of Pharmaceutical and Medical Research

    109

    Baldo et al, [10]

    presented their results on primary tumours

    of the external auditory canal (EAC) while Gurgel et

    al, [11]

    published one of the most extensive review on

    middle ear carcinomas. Though, Stell et al. [12]

    reported

    no difference between the outcomes of tumours

    originating in EAC and middle ear, it is well known from

    the distinguishably recognized work of Spector et al, [13]

    that the more medial and deep is the invasion of the

    tumour, the more disappointing is the prognosis, such

    that all efforts towards treatment would be futile unless

    one resolves to more radical surgical management which

    may be accompanied by adjuvant therapy. Kawana et

    al. [14]

    have reported clear differences in outcomes for the

    two sites. To give an overview of middle ear carcinomas,

    it is pertinent to elaborate the study by Gurgel et al

    (2004) who presented an analysis of the SEER Database

    to bring out patterns of incidence, treatment and survival

    of primary middle ear carcinomas over a period

    extending from 1973 to 2004. The 5-year observed

    survival rate for 215 patients was 36.4%. This large

    sample size included 62.8% squamous cell carcinomas,

    18.2% adenocarcinomas, 13% were other carcinomas,

    while 6% were noncarcinomas. 31.2% patients had been

    treated by surgery, 16.3% by radiation, 38.6% by surgery

    with postoperative radiotherapy and 8.4% had no

    treatment. The 5-year survival rates for these four groups

    were 69.2%, 14.6%, 26.4% and 0% respectively. A

    similar study has been presented by Shen et al. [15]

    in

    2014. The 5-year overall and cause-specific survival

    rates for 247 patients with middle ear carcinoma were

    47.4% and 58% respectively.

    Diagnosis “Thou search for truth as a seeker, true colours will

    bleed”. Such is the diagnosis for temporal bone

    malignancies, many a times hidden to the untrained mind

    more than the untrained eye. It is but for the veil of usual

    symptomatology that conceals the hidden malignancy,

    such that repeated biopsies would be required in most of

    the cases. Directions are less and misdirection more, the

    surgeon has be persistent in his effort to uncover the true

    pathology. Often, the symptoms would merely be

    reported as otorrhoea and pruritis. Though less

    commonly, there may be an obvious classical

    presentation consisting of bloody discharge with tinnitus,

    facial paralysis, severe pain, vertigo or sensorineural

    hearing loss. An unforgiving deep temporal pain usually

    signifies bony or dural invasion. As for the time of onset,

    the patient may report a duration of symptoms from 4

    months to 4 years. [7]

    There could be a history of previous

    mastoid surgery, such that the diagnosis awaits several

    biopsy attempts, for the histopathologic assessment is

    further complicated by tissue necrosis, secondary

    infection and haemorrhage. The finding of trismus

    should alert the clinician towards possibility of

    infratemporal fossa or involvement of

    temporomandibular joint, due to invasion of medial or

    lateral pterygoid muscles.

    Preoperative imaging for accurate mapping of

    boundaries for resection is indispensable. While CT

    scans can reveal areas of bone erosion, MRI is required

    to elaborate spread of tumour along neural pathways,

    vascular channels, intracranial extension and

    involvement of extra-temporal soft tissues. The

    experienced observer would keep in mind the pathways

    of invasio