MRI and FDG PET/CT Findings of Primary Orbit Leiomyosarcoma

Primary Leiomyosarcoma of the Orbit and Conjunctiva: A Report of Four Cases With a Review of the Literature

Leiomyosarcomas (LMS) are common soft tissue tumors in the body. Primary orbital and conjunctival LMS are, however, rare. Herein, we describe the diverse clinical presentations, histopathological features, and management outcomes of three cases of primary LMS of the conjunctiva and one case of primary orbital LMS. The first patient was a 40-year-old female with primary orbital LMS who developed recurrence following wide local excision. The remaining three cases were primary conjunctival LMS. All four patients underwent orbital exenteration and were disease-free at a mean follow-up period of 18.64 months. LMS is known for local recurrences and metastasis. Complete surgical excision and prompt adjuvant radiotherapy can improve the prognosis.

Unexpected Origin of Lung Metastases: Rare Colon Leiomyosarcoma Detected by 18F-FDG PET/CT

ABSTRACT

A 49-year-old woman was referred to our hospital due to suspected lung metastases for 1 month. She had a history of thyroid micropapillary carcinoma and uterine leiomyomas. An 18F-FDG PET/CT scan, which was performed to search the source of the presumed metastasis of the disease, showed multiple lung metastases and 2 18F-FDG-avid foci in the thyroid and colon. Biopsy of lung and resection of colon lesions were then performed, and the disease was finally identified to be rare primary colon leiomyosarcoma with multiple lung metastases.

Primary Inferior Vena Cava Leiomyosarcoma With Hepatic Metastases on FDG PET/CT

ABSTRACT

Leiomyosarcomas originating from the inferior vena cava are very rare malignant tumors with an extremely poor prognosis. We report FDG PET/CT findings of pathology-proven hepatic metastases from leiomyosarcoma originating from the inferior vena cava in a young woman whose initial presentation was worsening abdominal and chest pain.

Primary Orbital Leiomyosarcoma in an Adult Male

A 71-year-old male presented with a history of noticing gradual painless progressive proptosis along with a pinkish mass seen on the outer aspect of his left eyeball. Orbital CT revealed a fairly defined homogenous lesion, abutting the left eyeball and involving the lateral orbit reaching almost till orbital apex. Histopathology analysis aided with immunohistochemistry after an incision biopsy was consistent with leiomyosarcoma. Positron emission tomography scan ruled out presence of any distant primary or metastatic tumor. He underwent eyelid sparing total orbital exenteration with confirmed tumor free soft-tissue margins. He is doing well at 5 months of follow-up with no sign of local recurrence or distant metastasis. Primary orbital leiomyosarcoma is a rare tumor. It is mainly found in older woman; it is even rarer in males. Complete surgical excision with tumor free margins is the recommended treatment. Histopathology and immunohistochemistry are valuable in diagnosis and management.

The Monocle Sign in FDG-PET: A Sign of Contralateral Facial Nerve Palsy

We report three cases of unilateral F-FDG uptake in the orbicularis oculi muscle in subjects with contralateral peripheral facial nerve palsy. We argue that this asymmetric uptake pattern in fact reflects lack of metabolism on the side affected by facial nerve palsy, owing to denervation. Since the unilateral periorbital uptake resembles a monocle, we chose to call this finding the monocle sign. The monocle sign should not be confused with inflammation or tumor, but should prompt a neurological assessment for facial nerve palsy and a potential underlying disease.

Conjunctival Leiomyosarcoma, a Rare Neoplasm Always Originating at the Limbus? Report of a New Case and Review of 11 Published Cases

PURPOSE OF THE STUDY

To describe the differential diagnosis and management of a rare conjunctival malignancy.

PROCEDURES

A 79-year-old man presented with a conjunctival mass at the limbus. Excisional biopsy revealed a malignant mesenchymal tumor with myogenic differentiation. Six months later, three suspect lesions developed at the border of the previous excision. Pathological diagnosis pointed to a leiomyosarcoma. Adjuvant radiotherapy with strontium-90 brachytherapy was applied. After 3 years, there was neither recurrence nor distant metastases. A literature review revealed 11 cases of conjunctival leiomyosarcoma.

RESULTS

All 12 cases seemed to originate at the limbal conjunctiva. Scleral invasion was found only in one patient with multiple previous resections. Corneal invasion was reported in two patients. Four patients had a globe-sparing resection. In two of them, margins were not tumor free and additional brachytherapy gave a tumor-free follow-up of 1 and 3 years. Four cases underwent an exenteration.

CONCLUSION AND MESSAGE

Primary conjunctival leiomyosarcoma is a rare tumor with a favorable prognosis due to early detection and consequently limited size. Diagnosis involves histopathological investigation including immunohistochemistry. If possible, complete resection has the best prognosis. Adjunctive radiotherapy can be effective when the margins are not free and should be considered.

Orbital Metastasis: Rare Initial Presentation of an Occult Gall Bladder Carcinoma

Orbital metastases are known to arise from primary breast carcinoma followed by prostate, malignant melanoma, and lung carcinoma. We report a case of orbital metastasis as the initial presentation of an occult primary gall bladder carcinoma. The FDG PET/CT helped in localizing the occult distant primary site, which previously escaped detection, and also enabled the evaluation of orbital metastasis.