Row of tombstones appearance is seen in –
**Core Concept**
The "row of tombstones" appearance is a characteristic histopathological feature seen in certain conditions, particularly those affecting the bone marrow or lymphoid tissues. This appearance is typically observed under a microscope in histopathological sections.
**Why the Correct Answer is Right**
The "row of tombstones" appearance is classically seen in hairy cell leukemia, a type of cancer that affects the blood and bone marrow. In hairy cell leukemia, the neoplastic cells accumulate in the bone marrow and spleen, leading to a characteristic histological appearance. The neoplastic cells are arranged in a linear fashion, resembling a row of tombstones, due to their uniform shape and size. This appearance is a result of the cells' infiltration into the bone marrow and their subsequent aggregation.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the "row of tombstones" appearance is not typically associated with other types of leukemia, such as acute myeloid leukemia (AML) or chronic lymphocytic leukemia (CLL).
**Option B:** This option is incorrect because the "row of tombstones" appearance is not a characteristic feature of lymphoma, a type of cancer that affects the immune system.
**Option C:** This option is incorrect because the "row of tombstones" appearance is not typically seen in plasma cell myeloma, a type of cancer that affects the plasma cells in the bone marrow.
**Clinical Pearl / High-Yield Fact**
It's essential to recognize the "row of tombstones" appearance in hairy cell leukemia, as it is a key diagnostic feature of this condition. This appearance can be distinguished from other types of leukemia and lymphoma by its unique histological characteristics.
**Correct Answer: B. Lymphoma.**