Baylor University Medical Center Proceedings October 2017 - 458

stopped smoking, she has experienced
no additional recurrence of her IP.
The primary treatment modality for this benign disease is surgical.
Mitchell et al reported a combined
lateral and anterior skull base approach for extirpation of the eustachian tube in order to deﬁnitively
manage malignant transformation of
IP in this area (6). Complete excision
of the tumor is important to reduce
Figure 2. Hematoxylin and eosin stains demonstrating (a) middle ear inverted papilloma with moderate to severe the risk of recurrence. Recurrence
rates with mucosal stripping have
dysplasia (100×) and (b) numerous mitotic figures within middle ear inverted papilloma (400×).
been measured at 52.2%, whereas
drilling the tumor base, cauterizing the tumor base, and comAt 3-year follow-up from her last procedure, the patient
plete excision have recurrence rates of 4.9%, 4.7%, and 0%,
showed no evidence of tumor persistence or recurrence in the
respectively. Recurrence at the tumor base is thought to be
nose or the ear. Follow-up magnetic resonance imaging (MRI)
caused by rests of abnormal epithelium or tumor within the
at that time was also negative for disease. The current plan
of treatment involves close observation with serial MRI and
bone (10). Radiation, though not used routinely in most cases
endoscopic surveillance of the nasal cavity and middle ear. The
of IP, has been used as adjuvant therapy in certain cases. To date,
patient has been discussed at the multispecialty tumor board
there are no deﬁnitive recommendations regarding the role of
for possible radiation in the future should her disease develop
radiation in treating this rare entity.
malignant transformation.
In this case, the authors will continue close observation
and serial imaging. They have had thorough discussions with
DISCUSSION
the patient regarding adjuvant radiation due to the recurrent
Middle ear involvement with IP is an unusual ﬁnding that
nature of her tumor with severely dysplastic features. This case
is rarely reported in the literature. There are three theories for
underscores the need for further data on this topic.
the development of temporal bone IP: direct spread of tumor
1. Wood JW, Casiano RR. Inverted papillomas and benign nonneoplastic
through the eustachian tube, conversion of ectopic rests of
lesions of the nasal cavity. Am J Rhinol Allergy 2012;26(2):157-163.
Schneiderian membrane in the temporal bone, and embolic
2. Anari S, Carrie S. Sinonasal inverted papilloma: narrative review. J Laryngol
seeding of tumor cells outside the sinonasal tract (3). The most
Otol 2010;124(7):705-715.
common presenting symptoms of temporal bone IP are hear3. Shen J, Baik F, Mafee MF, Peterson M, Nguyen QT. Inverting papilloma
ing loss and otorrhea (5). Middle ear IP is associated with an
of the temporal bone: case report and meta-analysis of risk factors. Otol
Neurotol 2011;32(7):1124-1133.
increased risk of malignancy, particularly if the lesions are recur4. Dingle I, Stachiw N, Bartlett A, Lambert P. Bilateral inverted papilloma of
rent (3). A recent series of 32 patients with temporal bone IP
the middle ear with intracranial involvement and malignant transformareported invasive carcinoma in 28% of patients and carcinoma
tion: ﬁrst reported case. Laryngoscope 2012;122(7):1615-1619.
in situ in 16% (5).
5. Carlson ML, Sweeney AD, Modest MC, Van Gompel JJ, Haynes DS, Neﬀ
The middle ear lesion in this case demonstrated HPV 11
BA. Inverting papilloma of the temporal bone: report of four new cases and
systematic review of the literature. Laryngoscope 2015;125(11):2576-2583.
positivity. Nasal IPs have been associated with this and other
6. Mitchell CA, Ebert CS, Buchman CA, Zanation AM. Combined transHPV isotypes (7). However, HPV 16 and 18 have been more
nasal/transtemporal management of the eustachian tube for middle ear
classically associated with malignancy. A recent meta-analysis
inverted papilloma. Laryngoscope 2012;122(8):1674-1678.
of 31 case-controlled studies showed statistically signiﬁcant as7. Shen J, Tate JE, Crum CP, Goodman ML. Prevalence of human papillosociation of high-risk HPV subtypes 16 and 18 with malignant
maviruses (HPV) in benign and malignant tumors of the upper respiratory
tract. Mod Pathol 1996;9(1):15-20.
sinonasal IP-with type 18 having a stronger association with
8.
Zhao RW, Guo ZQ, Zhang RX. Human papillomavirus infection and
malignancy than type 16 (8). The role of HPV in the developthe malignant transformation of sinonasal inverted papilloma: A metament of IP has yet to be elucidated. Additionally, the clinical
analysis. J Clin Virol 2016;79:36-43.
signiﬁcance of isolating HPV in the middle ear specimen but not
9. Roh HJ, Mun SJ, Cho KS, Hong SL. Smoking, not human papilloma
in the nasal specimen is unclear. Roh et al performed a retrospecvirus infection, is a risk factor for recurrence of sinonasal inverted papilloma. Am J Rhinol Allergy 2016;30(2):79-82.
tive review of 54 patients and found no signiﬁcant diﬀerence in
10. Healy DY Jr, Chhabra N, Metson R, Holbrook EH, Gray ST. SurgiHPV status and rate of recurrence; in the same review, there was
cal risk factors for recurrence of inverted papilloma. Laryngoscope
an association between smoking and IP recurrence, although this
2016;126(4):796-801.
ﬁnding was not statistically signiﬁcant (9). Since our patient has
a

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