Pathologic findings:
Consists of a fragment of skin and several small loose fragments of
tissues weighing a total of 45 gm. The main fragment measures 7.0x4.0x3.0
cm in dimension. Cut surfaces have a diffuse fatty and pale brownish appearance.
| Fig 1: Low power skin | Fig 2: Low power | Fig 3: Low power | Fig 4: Low power |
| Fig 5: Vascular proliferation | Fig 6: Vascular proliferation | Fig 7: Low power eosinophilia | Fig 8: High power eosinophilia |
Sections show that the tissues excised consists of lobules and nodules of proliferating lymphoid tissues separated by abundant fibrosis. These nodules consist of hyperplastic lymphoid tissues accompanied by reactive germinal centre formation, numerous eosinophils and increase in high endothelial venules. Some of the germinal centres are partially destroyed by fibrinoid deposits and necrosis. Microscopic eosinophilic abscesses are seen.
Pathologic Diagnosis:
Tumour right ear lobe - Recurrent Kimura's disease confirmed.
Pathologist Comments:
Kimura's disease is a chronic inflammatory condition which presents with a characteristic triad of signs and symptoms, namely a painless, slowly enlarging soft tissue mass in the head and neck region, associated lymphadenopathy and peripheral eosinophilia. Its etiology is unknown but is thought to be a manifestation of an aberrant allergic response. It was first reported by Chinese authors Kimm and Szeto (1) in 1937. The definitive description was published by Kimura et al (2) in Japan in 1948. The disease is most prevalent in Asians and eighty-five per cent of cases occur in men. The typical presentation is in a young Oriental male with nontender subcutaneous swellings in the head and neck region, lymphadenopathy, peripheral eosinophilia, and elevated serum IgE. The parotid glands may be involved (3). There may also be proteinuria.
In Kimura's disease there is classically a dense inflammatory infiltrate characterized by proliferating lymphoid tissue with germinal centres, eosinophilic microabscesses and fibrosis. There is often marked fibrosis. The lesion need to be distinguished from angiolymphoid hyperplasia with eosinophilia (ALHE), which is believed to be a true neoplasm of the endothelium (4).
The histology of ALHE is typified by an exuberant proliferation of capillary
vessels some of which may not be canalized. These are lined by epithelioid
(histiocytoid) endothelial cells which are not seen in Kimura's disease.
While there is an inflammatory infiltrate, the associated lymphocytes are
not arranged in germinal centres as they are in Kimura's disease. Clinically,
Kimura's disease is believed to be a disease of the Orient, and ALHE one
of the western world. ALHE occurs in older (20-40 years), predominantly
female populations. Kimura's disease is primarily a disease of younger
males.
| Kimura's Disease | ALHE | |
| Predominant occurrence | Oriental | Western population |
| Age / Sex | Younger patients, male | Older patients, female |
| Nature | Reactive | Endothelial neoplasm |
| Eosinophilic microabscess | Yes | No |
| Histiocytoid endothelium | No | Yes |
| Lymphoid follicles | Common | Sometimes |
| Other features | Raised Se IgE, Eosinophilia, Proteinuria |
Treatment options range from conservative observation for asymptomatic patients to surgical excision, steroid therapy, and radiotherapy for symptomatic patients. The treatment of choice for localized disease would thus appear to be surgical excision. Conservative management is recommended in anatomically sensitive areas. There had been some case reports in the otorhinolaryngeal, plastic surgery and ophthalmic specialties reflecting problems in management when this lesion affects important anatomical structures. For refractory lesions, low-dose radiation (5) had been able to help some patients wean off corticosteroids. Recently cyclosporin had also been reported to be successful in treatment (6).
There have been reports of recurrence in 15 to 40% of cases (7) and some cases apparently persists for years.
References:
