Table I.
Proposed TNM staging system for BIA‐ALCL, adapted from Clemens et al. 34
| Description of lymphoma cells | Stage | ||
|---|---|---|---|
| T = Tumour extent (penetration of capsule) | |||
| T1 | Only in the effusion or on luminal side of the capsule | 1A | T1N0M0 |
| T2 | Superficial infiltration of the luminal side of the capsule | 1B | T2N0M0 |
| T3 | Cell aggregates/sheets penetrate the capsule | 1C | T3N0M0 |
| T4 | Cells infiltrate beyond the capsule | 2A | T4N0M0 |
| N = Node extent | |||
| N0 | No lymph node involvement | ||
| N1 | One local/regional node involved | 2B | T1‐3N1M0 |
| N2 | More than one local/regional node involved | 3 | T4N1‐2M0 |
| M = Metastatic disease | |||
| M0 | No involvement of distant sites | ||
| M1 | Disease present at distant sites | 4 | T1‐4N0‐2M1 |
TNM, tumour‐node‐metastasis; BIA‐ALCL, Breast Implant‐Associated Anaplastic Large Cell Lymphoma.