Metastasis to the External Auditory Canal: A Systematic Review

OBJECTIVE

To systematically review the literature and understand the behavior, diagnosis, management, and mortality of metastasis to the external auditory canal (EAC).

DATABASES REVIEWED

PubMed/Medline, EMBASE, Web of Science.

METHODS

Studies from 1948 to June 2023 describing metastasis to the EAC were included. Non-English literature was excluded. Data extraction: Study design, age, sex, pathology, primary site, staging, additional sites of metastasis, time to EAC metastasis from diagnosis, time from diagnosis of EAC metastasis to death, symptoms, exam and imaging findings, and management.

RESULTS

Data were synthesized qualitatively with means calculated. Thirty-two studies met the criteria, totaling 37 patients with EAC metastasis. Mean age was 58 years; 73% were male. The most common pathologies were adenocarcinoma (37.8%), acute myelogenous leukemia (8.1%), and renal cell carcinoma (8.1%). Sites of primary malignancy were hematologic (10.8%), breast (8.1%), esophagus (8.1%), renal (8.1%), and prostate (8.1%). Within the temporal bone, 73% had isolated EAC metastasis. Median time to EAC metastasis from the diagnosis of primary malignancy was 18 months. Metastasis to the EAC was the first presentation of malignancy in 21.6% of patients. Median time to death was 4.5 months. Symptoms included hearing loss (59.5%), otalgia (27.0%), otorrhagia (24.3%), facial paralysis (21.6%), otorrhea (16.2%), and aural fullness (13.5%). On imaging, bony erosion was present in 50% of cases. Treatment was primarily palliative with excision and radiation.

CONCLUSIONS

EAC metastasis has a distinct presentation from other temporal bone subsites. Early biopsy to establish a diagnosis and intervene is critical.

Metastatic Disease of the Temporal Bone: A Contemporary Review

OBJECTIVES

To identify the frequency and primary site of metastatic pathologies to the temporal bone and characterize the associated symptomatology.

METHODS

The MEDLINE, Embase, and Web of Science databases were systematically reviewed according to the PRISMA guidelines to identify all cases of pathologically confirmed distant temporal bone metastases published with English translation until October 2019. Descriptive statistics were performed.

RESULTS

Out of 576 full-length articles included for review, 109 met final criteria for data extraction providing 255 individual cases of distant temporal bone metastases. There was a male predominance (54.9%) with median age of 59.0 years (range 2-90). The most common locations of primary malignancy included the breasts (19.6%), lungs (16.1%), and prostate (8.6%). Most tumors were carcinomas of epithelial origin (75.3%) and predominantly adenocarcinoma (49.4%). The commonest metastatic sites encountered within the temporal bone were the petrous (72.0%) and mastoid (49.0%) portions. Bilateral temporal bone metastases occurred in 39.8% of patients. Patients were asymptomatic in 32.0% of cases. Symptomatic patients primarily reported hearing loss (44.3%), facial palsy (31.2%), and otalgia (16.6%) for a median duration of 1 month. Petrous lesions were associated with asymptomatic cases (P = .001) while mastoid lesions more often exhibited facial palsy (P = .026), otalgia (P < .001), and otorrhea (P < .001). Non-carcinomatous tumors were associated with petrosal metastasis (P = .025) and asymptomatic cases (P = .109). Carcinomatous metastases more often presented with otalgia (P = .003).

CONCLUSIONS

Temporal bone metastasis is uncommon but should be considered in patients with subacute otologic symptoms or facial palsy and history of distant malignancy. Laryngoscope, 131:1101-1109, 2021.

Middle ear metastasis from dormant breast cancer as the initial sign of disseminated disease 20 years after quadrantectomy

We describe an unusual case of breast cancer metastatic to the middle ear in a 71-year-old woman. The metastasis was the initial sign of disseminated disease 20 years after the patient had undergone a quadrantectomy for her primary disease. Computed tomography (CT) demonstrated the presence of an intratympanic mass with a soft-tissue density that was suggestive of chronic inflammation. The patient underwent a canal-wall-down tympanoplasty. When a brownish mass was found around the ossicles, a mastoidectomy with posterior tympanotomy was carried out. However, exposure of the tumor was insufficient, and therefore the posterior wall of the ear canal had to be removed en bloc. Some tumor was left on the round window membrane so that we would not leave the patient with a total hearing loss. Our case highlights the limitations of CT and magnetic resonance imaging in differentiating inflammatory and neoplastic lesions.

Tackling hepatitis B virus-associated hepatocellular carcinoma--the future is now

Hepatocellular carcinoma (HCC) is one of the most lethal and prevalent cancers in many developing countries including India. Among the various etiological factors being implicated in the cause of HCC, the most important cause, however, is hepatitis B virus (HBV) infection. Among all HBV genes, HBx is the most critical carcinogenic component, the molecular mechanisms of which have not been completely elucidated. Despite its clinical significance, there exists a very elemental understanding of the molecular, cellular, and environmental mechanisms that drive disease pathogenesis in HCC infected with HBV. Furthermore, there are only limited therapeutic options, the clinical benefits of which are insignificant. Therefore, the quest for novel and effective therapeutic regimen against HBV-related HCC is of paramount importance. This review attempts to epitomize the current state of knowledge of this most common and dreaded liver neoplasm, highlighting the putative treatment avenues and therapeutic research strategies that need to be implemented with immediate effect for tackling HBV-related HCC that has plagued the medical and scientific fraternity for decades. Additionally, this review proposes a novel "five-point" management algorithm for HBV-related HCC apart from portraying the unmet needs, principal challenges, and scientific perspectives that are relevant to controlling this accelerating global health crisis.