SEER Inquiry System - Search

Per pathology report

• Lung, right lower lobe, wedge excision (A): Invasive moderately differentiated adenocarcinoma with focal lepidic pattern (pT1a, pN0).

• Right lower lobe, completion lobectomy (F): Separate focus of well differentiated adenocarcinoma with lepidic pattern (<4mm) (see comment).

• COMMENT: The block F7 shows a microscopic focus of adenocarcinoma with lepidic growth pattern. This most likely represents a separate primary tumor since the stapled margins were all negative for involvement. This focus measures less than 0.4 cm.

• Tumor focality: Most likely two separate primary tumor nodules. Histologic type: adenocarcinoma, mixed type (NOS and lepidic type).

The tumor board has staged this as two separate primaries and is treating it as such. They are not considering the second focus metastatic even though it is the same histology. Lepidic is not in the ICD-O-3. Is lepidic a new term for histology?

There are four invasive tumors in the right lung:

Large cell undifferentiated carcinoma in the right lower lobe (8012/3, C343);

Adenocarcinoma, acinar-predominant in the right lower lobe (8551/3, C343) that was 0.7 cm in size and limited to the lung;

Mucinous adenocarcinoma in the right upper lobe (8253/3, C341) that was 0.9 cm and limited to the lung;

Adenocarcinoma, NOS also in the right upper lobe (8140/3, C341) that was 1 cm and limited to the lung.

The Lung M Rules confirm the large cell undifferentiated carcinoma is a separate primary from the three adenocarcinoma tumors (Rule M8). The acinar adenocarcinoma and mucinous adenocarcinoma tumors are separate primaries (Rule M6). The adenocarcinoma, NOS tumor is the same primary as both the acinar and mucinous are adenocarcinomas (Rule M7).

How is Primary Site coded for both the acinar and mucinous adenocarcinomas if they represent multiple tumors reported as a single primary (when compared to the adenocarcinoma, NOS tumor)?

Should the adenocarcinoma, NOS tumor also be included when coding EOD Primary Tumor for both the right lower lobe acinar adenocarcinoma and right upper lobe mucinous adenocarcinoma primaries? Further follow-up with the physician is not possible.

Chest x-ray: Multifocal pneumonia in left lung; possibility of masses in left lung not excluded.

Chest CT: 4 large ground-glass masses in LUL (largest 46mm); beginning of Tree-In-Bud appearance in LUL; 2 small ground-glass nodules in right lung.

Lung LUL biopsy: Adenocarcinoma, Solid Predominant.

No further information as patient did not want to discuss treatment options.

Per the AJCC book and CAnswer Forum, multifocal classification should be applied equally whether the lesions are in the same lobe OR in different ipsilateral lobes OR contralateral lobes, cT2b(m), cN0, cM0.

The mediastinal nodes were submitted as a separate specimen. The patient also had several peribronchial nodes identified within the lobectomy specimen.

Does code 33 (Lobectomy with mediastinal lymph node dissection) require a complete mediastinal lymph node dissection (i.e. the removal of all lymph nodes in mediastinal chain(s) as opposed to a selective sampling/dissection of lymph nodes from multiple mediastinal chains)?

The patient was diagnosed with a biopsy-proven 12/2020 LUL SCC treated with radiation only, followed by a right hilar lymph node biopsy in 07/2022, that proved “metastatic pulmonary adenocarcinoma” per pathology and treated with radiation, followed by a biopsy-proven 12/2022 RLL SCC to be treated with immunotherapy only. The imaging never definitively identified a lung tumor that can be assumed to be a primary adenocarcinoma tumor.  In 06/2022, a PET scan only described a “strongly PET positive Rt inferior hilar LN vs infrahilar pulmonary mass,” as well as the subsequently biopsy-proven SCC in the RLL (12/2022 SCC primary). The biopsy path indicates this was a right hilar lymph node metastasis and does not indicate this is an infrahilar pulmonary mass. No other PET positive pulmonary lesions were seen at the time.

The oncologist’s assessment indicates the right hilar node was the only positive finding on the biopsy, and it was unclear if this right hilar node metastasis was from the left lung or if the primary was “not detectable.” The oncologist summarized this as a LUL lung lesion radiated for SCC, a right hilar lesion radiated for adenocarcinoma, and a RLL lung lesion on pathology found to be SCC.

Should the interval occurring metastatic adenocarcinoma be accessioned as a separate lung, NOS primary based on the histology difference? While the Solid Tumor Rules do not apply to metastasis, the oncologist did treat these three malignancies separately and does not indicate the hilar lymph node metastasis was felt to be from either SCC primary.

Per Mayo consulting pathologist, the final diagnosis on this right lung biopsy is: SMARCA4-deficient malignant neoplasm (see Comment). Comment: Sections show a poorly-differentiated malignant neoplasm without any apparent glandular, squamous, or stromal differentiation. The tumor near totally replaces the underlying lung tissue without recognizable underlying alveolar parenchyma. Immunohistochemical stains performed at Mayo Clinic (Oscar keratin, INSM1, NUT, S100, desmin and BRG1 protein encoded by SMARCA4 gene) demonstrate that the malignant cells are positive for Oscar keratin (rare cells only), synaptophysin (weak/patchy) and p63 (focal) while negative for the remaining antibodies tested. Of note, SMARCA4 stain is negative in the tumor cells. Thus, this tumor can be categorized as a SMARCA4-deficient malignant neoplasm, which is known to be an aggressive malignancy, likely represent a SMARCA4-deficient thoracic sarcoma, a recently described entity. SMARCA4-deficient carcinomas in the lung have been reported to be mostly adenocarcinomas or squamous cell carcinomas, which would not fit for this case. Please refer to a paper published by our group (Sauter JL et al. Mod Pathol 2017;30:1422-32.