Malignant Melanoma Presenting as a Mediastinal Malignant Melanoma Presenting as a Mediastinal Unknown Primary Origin?

The most common site of primary malignant melanoma is the skin, however, virtually any organ system may be involved. Metastatic melanoma of unknown primary origin accounts for approximately 2-6% of all melanoma cases. The mediastinum as the site for malignant melanoma is extremely rare, both as a primary or metastatic lesion. Primary malignant melanoma of mediastinum is very rare with only a handful of reports in the literature. We hereby report a rare case of malignant melanoma of mediastinum in a 31 year old male who was initially misdiagnosed on fine needle aspiration cytology as adenocarcinoma for which he received chemotherapy with clinical deterioration. Even on extensive meticulous search, no primary was discovered.

Large cell lung carcinoma with rhabdoid phenotype: Report of a rare entity presenting with chest wall involvement.

Large cell lung carcinoma (LCLC), rhabdoid phenotype (RP) is a rare entity, accounting for 0.1-1% of all lung tumors. It is characterized by presence of more than 10% cells with rhabdoid morphology-large cells with abundant cytoplasm, eccentric nuclei, prominent nucleoli and eosinophilic cytoplasmic inclusions. We report a case of rhabdoid variant of large cell carcinoma in a 65-year-old female. Patient presented with a lump in the right axilla. Computed tomography showed a large mass lesion in right lung with involvement of the chest wall. Tru-cut biopsy from the lung lesion was performed and histopathology was compatible with LCLC. A RP was considered due to the presence of tumor cells with eosinophilic cytoplasmic globules and eccentric nuclei. Cytokeratin and vimentin were diffusely positive while thyroid transcription factor was focally positive. INI-1, desmin, calretinin, HMB-45, and neuroendocrine markers were negative. This case highlights that recognition of large cell carcinoma lung, RP is very important because of its aggressive nature and adverse outcome.

Coexistence of metastatic breast carcinoma and primary tuberculosis in axillary lymph nodes: a report of a rare case.

Concomitant breast cancer metastasis and tubercular lymphadenitis in axillary lymph node is an extremely rare occurrence. Axillary lymph node metastasis is the most important factor in the staging of breast carcinoma and the number of axillary nodes showing metastases alters the stage. As tuberculosis also produces nodal enlargement, this can mimic or complicate the staging of malignant disease. Dual pathology in an organ can lead to difficulties in interpretation and inappropriate treatment of tuberculosis as well as carcinoma breast. Moreover, fine needle aspiration cytology (FNAC) from such cases may be misleading if only one of the diseases is picked up. Therefore, the need for multiple attempts at FNAC should be stressed upon for all palpable lumps. We report a case of infiltrating duct carcinoma breast in a 45-year-old female where tuberculosis was discovered in axillary lymph nodes in addition to metastases. As the present case led to incidental discovery of tuberculosis with tumor metastasis, it reinforces the possibility of a coexistent lesion in the pathologists' mind, especially in regions endemic for tuberculosis.

Disseminated tuberculosis in a patient with recurrent transitional cell carcinoma of renal pelvis and bladder following intravesical BCG therapy: A report of a rare case.

Bacillus Calmette-Guerin (BCG) has been used as an intravesical instillation for nonmuscle invasive (superficial) bladder cancer for the last 3 decades. Although intravesical BCG therapy is well-tolerated by most of the patients, adverse reactions have also been reported which are usually local, benign, and self-limited. Systemic complications such as miliary tuberculosis (TB) are very rare with few documented reports in literature. We hereby report a rare case of disseminated TB in bilateral lungs, adrenal, cervical, mediastinal, and para-aortic lymph nodes in a patient with recurrent transitional cell carcinoma (TCC) of renal pelvis and urinary bladder. Peculiar feature of this case was the development of TB 2 years following last BCG instillation, which is unlike most of the cases in the literature where TB developed within few weeks of last dose of BCG.

Mucinous carcinoma of breast with psammomatous calcification: report of a rare case with extensive axillary metastases.

Pure mucinous carcinoma of the breast accounts for about 2% of all breast carcinomas and is associated with a favourable prognosis due to its lower nuclear grade and infrequent axillary or hematogenous metastases. Micropapillary variant of mucinous carcinoma breast has recently received attention as a unique form of invasive carcinoma of the breast exhibiting dual differentiation towards mucinous as well as micropapillary. The characteristic features for labeling a tumor as mucinous micropapillary carcinoma are micropapillary pattern, nuclear pleomorphism, hobnail cells and psammoma bodies in addition to the predominant mucinous component. Micropapillary mucinous carcinoma (MUMPC) when compared to pure mucinous carcinoma tends to have a higher nuclear grade, axillary lymph node metastases, lymphovascular invasion and overexpression of Her 2, p53 and Ki-67, thereby displaying an aggressive clinical behaviour. We present a rare case of micropapillary mucinous carcinoma to highlight the fact that this being a unique and rare variant of mucinous carcinoma should be recognized and reported as a separate category by the pathologists owing to its aggressive clinical behaviour and its influence on the nature of therapy.