Solid Tumor Rules/Multiple Primaries--Head and Neck: Is a patient with 2020 neck mass, squamous cell carcinoma (SCC), p16-negative, who then had a biopsy of the right tonsil (C09.9) in July 2022, SCC p16-positive, one or two primaries? Is this coded to 8070/3 using pre-2022 rules or a new, second primary p16-positive, 8085/3. See Discussion.
Solid Tumor Rules (2018)/Multiple primaries--Breast: How many primaries should be reported for a December 2013 diagnosis of lobular carcinoma in situ (8520/2) in the left breast, treated with a lumpectomy, followed by a July 2018 diagnosis of invasive ductal carcinoma (8500/3) also in the left breast? See Discussion.
Solid Tumor Rules (2018)/Multiple primaries--Colon: Is a colorectal anastomotic site recurrence reportable, that is, a second primary, per Rule M7, third bullet, if there is no mention of mucosa but the tumor is seen on colonoscopy? See Discussion.
Solid Tumor Rules (2018, 2021/Multiple Primaries/)--Lung: How many primaries should be reported and what M rule applies when a diagnosis of presumed adenocarcinoma in situ (AIS) of the left lung follows a known diagnosis of progressive multifocal malignant adenocarcinoma in the right lung? See Discussion.
Solid Tumor Rules/Multiple Primaries--Breast: How many primaries should be accessioned for a diagnosis of invasive carcinoma of the left breast (8500/3) in 2020 followed by a 2023 diagnosis of dedifferentiated carcinoma in the left breast (8020/3)? See Discussion.
MP/H Rules/Histology--Breast: Which is the correct histology code to use and which MP/H rule applies in the case of a single lumpectomy specimen that demonstrates two separate tumors with the following histologies.
1) Invasive lobular carcinoma
2) Invasive ductal carcinoma with tubular features
Solid Tumor Rules/Multiple Primaries--Peripheral Nerves: How many primaries should be abstracted, and which M Rule applies, when a malignant peripheral nerve sheath tumor (MPNST) in the right arm (C471) is followed greater than one year later by a separate malignant peripheral nerve sheath tumor of the thoracic chest wall (C473)? See Discussion.
Solid Tumor Rules/Multiple Primaries--Breast: How many primaries are accessioned when a 2020 diagnosis of invasive ductal carcinoma treated by lumpectomy is followed by a 2023 diagnosis of invasive lobular carcinoma treated by mastectomy? See Discussion.
Solid Tumor Rules (2018)/Multiple primaries--Melanoma: Should a case with treatment delayed due to COVID-19 be abstracted as one or two primaries? It is uncertain if the invasive tumor would be a new tumor, or deeper extension/disease progression from the original tumor. See Discussion.
Multiple primaries--Heme & Lymphoid Neoplasms: How many primaries are accessioned when a patient is simultaneously diagnosed with systemic mastocytosis and chronic myelomonocytic leukemia (CMML-0) on a single bone marrow biopsy? See Discussion.