Osteoid osteoma is a benign tumor of the bone widely regarded as devoid of malignant capacity or invasive potential. Osteosarcoma is a highly aggressive tumor with generally unfavorable prognosis. We present a case of a 65-year-old woman who presented with a large thigh mass proved to be a dedifferentiated high-grade parosteal osteosarcoma arising from the left femur with metastasis to the ribs, spine, and pelvic bones. The patient reported history of osteoid osteoma at the same site of the current osteosarcoma surgically removed 46 years prior to current presentation. In this report, we describe the difference between osteoid osteoma and osteosarcoma, and attempt to answer the question of possible progression of osteoma to osteosarcoma, or if it is just a coincidence.

We report a case of a 37-year-old woman presenting with a 2.8 cm hypoechoic mass in the upper outer quadrant of the right breast. The original core and fine needle aspiration (FNA) at presentation led to the diagnosis of a fibroadenoma, however the cytopathologist noted few atypical cells insufficient for a malignant diagnosis. The mass was found to be enlarged in size at 3.6 cm at a follow up eleven months later. Repeat FNA and core biopsies demonstrated cytologic features of both fibroadenoma (FA) and invasive ductal carcinoma (IDC). Can a fibroadenoma progress into an invasive carcinoma? Or, is the presence of both of these modalities just a coincidence? We report this case with a brief literature review to investigate this phenomenon.

The diagnosis of pre-cancerous breast lesions is important to evaluate the risk of recurrence and progression to invasive carcinomas. In this report, we present a 35-year-old female with suspicious microcalcification foci consistent with atypical ductal hyperplasia, but short of the qualifying 2 mm size of low-grade ductal carcinoma in situ. We used high molecular weight cytokeratin (HMW-CK- 903) as a marker to further analyze the lesion. A final diagnosis of two small foci of low-grade DCIS in the background of ADH was rendered. In challenging cases, like our case here, the use of such markers can be useful to reach accurate diagnosis and guide management plan. This is especially true when the patient is pregnant, and the lesion is borderline on size for the arbitrary limit of 2 mm, which determines the upgrade of atypical ductal hyperplasia to low-grade ductal carcinoma in situ. After full resection of the lesion, the patient elected not to have post-operative radiation therapy and subsequently had no recurrence at 7 years follow-up. In this manuscript, we review the literature on the difference between, benign ductal hyperplasia, atypical ductal hyperplasia, ductal carcinoma in situ, and invasive carcinoma. We also discuss the importance of a proper diagnosis of pre-cancerous lesions, and how different treatments can be approached during pregnancy.

Adenoid cystic carcinoma is a rare malignancy involving exocrine mucus glands, typically presenting in the salivary glands of the head and neck, but also as a primary lung neoplasm. The intention of this report is to provide more insight to adenoid cystic carcinoma due to its rarity. We present a case of a 50-year-old non-smoking Hispanic man presenting with shortness of breath and the presence of lung nodules on imaging. Biopsy of one of the Lung nodules proved to be metastatic adenoid cystic carcinoma originating from a prior adenoid cystic carcinoma from the right submandibular gland. This case report discusses the diagnosis of metastatic Adenoid Cystic Carcinoma utilizing cytology samples obtained by Fine Needle Aspiration alone, without the need for surgical biopsy. We review the histological presentation, demographics, molecular basis, metastasis, and treatment of adenoid cystic carcinoma.