Metachronous primary non-small cell lung cancer and mucinous tubular and spindle cell carcinoma of the left kidney - A case report

Q: What is metachronous multiple primary malignant tumors (MPMTs) in this study?

MPMTs are two or more independent malignancies in different anatomical sites. They are classified as metachronous when the diagnoses occur outside the defined short interval, and are often linked to a poorer prognosis.

Q: How was the renal lesion diagnosed after lung adenocarcinoma treatment?

A routine CT follow-up at 10 months showed an ill-defined left renal mass. A partial nephrectomy was performed, and histopathological examination confirmed mucinous tubular and spindle cell carcinoma (MTSCC).

Q: Why is integrated histopathological and immunohistochemical evaluation emphasized?

The report highlights the need to distinguish rare primary cancers, like MTSCC, from metastasis. Integrated pathology and immunohistochemistry help guide appropriate therapy and accurate diagnosis.

Sep 22, 2026

Uploaded by Ophelia

Multiple primary malignant tumors (MPMTs) involve two or more independent malignancies at different anatomical sites. This case report describes the first documented metachronous occurrence of primary lung adenocarcinoma and renal mucinous tubular and spindle cell carcinoma (MTSCC). A 69-year-old man underwent radical lobectomy for stage IIB lung adenocarcinoma, then received adjuvant chemotherapy. Postoperative CT at 10 months identified an ill-defined left renal mass, confirmed as MTSCC after partial nephrectomy. No recurrence occurred after 3 years, emphasizing integrated histopathological and immunohistochemical assessment to distinguish rare primaries from metastasis.

LanguageEnglish

CategoryHealthcare

FormatPDF

Pages8

Reading Time20 min

AccessFree to download

Abstract

Introduction

MPMTs: definition, classification, and diagnosis

Renal MTSCC: rarity, pathology, and clinical behavior

Pathophysiological considerations for metachronous primaries

ONCOLOGY LETTERS 31: 157, 2026 Metachronous primary non‑small cell lung cancer and mucinous tubular and spindle cell carcinoma of the left kidney: A case report JIN‑XIA ZHAO 1 , WEI ZHU2 , JIE‑BIN PAN3 and PENG‑FEI SUN 1 1 Department of Radiotherapy, The Second Hospital of Lanzhou University, Lanzhou, Gansu 730000, P.R. China; 2 Department of Pathology, The Second Hospital of Lanzhou University, Lanzhou, Gansu 730000, P.R. China; 3 Department of General Surgery, The Second Hospital of Lanzhou University, Lanzhou, Gansu 730000, P.R. China Received August 6, 2025; Accepted February 13, 2026 DOI: 10. 3892/ol.2026.15510 Abstract. Multiple primary malignant tumors (MPMTs) refer to two or more independent malignancies occurring at different anatomical sites. The present study reports the first documented case of metachronous primary lung adenocarci‑ noma and renal mucinous tubular and spindle cell carcinoma (MTSCC). A 69‑year‑old man underwent a radical lobectomy for stage IIB (pT2aN1M0) lung adenocarcinoma followed by adjuvant chemotherapy. A routine 10‑month postoperative follow‑up computed tomography scan revealed an ill‑defined left renal mass . Subsequently, a partial nephrectomy was performed . Histopathological examination confirmed MTSCC. No recurrence was observed after 3 years of surveil‑ lance. The present study is, to the best of our knowledge, the first to report the association between lung adenocarcinoma and MTSCC, which highlights the necessity to consider a new primary malignancy in cancer survivors with new lesions. The present case highlights the critical role of integrated histopathological and immunohistochemical evaluation in distinguishing rare primary cancers, such as MTSCC, from metastasis, thus guiding appropriate therapy. Introduction Advances in diagnostics, treatment and patient longevity have contributed to the increasing incidence of multiple primary malignant tumors (MPMTs), defined as two or more histologi‑ cally distinct malignancies in a single individual (1) . MPMTs are classified as synchronous or metachronous based on the timing of diagnosis, with the latter often being associated with a poorer prognosis. First described in the late 19th century, Correspondence to: Professor Peng‑Fei Sun, Department of Radiotherapy, The Second Hospital of Lanzhou University, 82 Cuiyingmen, Chengguan, Lanzhou, Gansu 730000, P.R. China E‑mail: [ery_sunpf@lzu.edu.cn](ery_sunpf@lzu.edu.cn) Key words: multiple primary malignant tumors, lung cancer, mucinous tubular and spindle cell carcinoma, kidney cancer, metachronous cancers, case report formal diagnostic criteria for MPMTs were established by Warren and Gates (2) in 1932 and require each tumor to be: i) Pathologically malignant, ii) histologically distinct and iii) not representing metastasis of the other tumor. Malignancies diagnosed within a 6‑month interval are considered synchro‑ nous (2) . The reported incidence of MPMTs ranges from 0.52 to 11.7%, with a higher prevalence in men >50 years old, and the most common combination is adenocarcinoma and squamous cell carcinoma (3) . Established risk factors include smoking and heavy alcohol intake (4,5) . In addition, patients with MPMT may have a family history of cancer, while other patients are sporadic and may possess DNA mismatch repair gene mutations (6) . The diagnosis of MPMTs relies on patho‑ logical, histological and immunohistochemical examinations, although no standardized treatment guidelines are available at present. Due to the current lack of standardized treatment guidelines, management is individualized and based on tumor pathology, stage and patient tolerance, ranging from radical to palliative intent. MTSCC of the kidney is an extremely rare malignant epithelial tumor of the kidney, accounting for <1% of all primary renal tumors (7) . Recognized as a distinct entity in the 2004 World Health Organization (WHO) classification (8), MTSCC predominantly affects middle‑a

FAQs

What is metachronous multiple primary malignant tumors (MPMTs) in this study?

MPMTs are two or more independent malignancies in different anatomical sites. They are classified as metachronous when the diagnoses occur outside the defined short interval, and are often linked to a poorer prognosis.

How was the renal lesion diagnosed after lung adenocarcinoma treatment?

A routine CT follow-up at 10 months showed an ill-defined left renal mass. A partial nephrectomy was performed, and histopathological examination confirmed mucinous tubular and spindle cell carcinoma (MTSCC).

Why is integrated histopathological and immunohistochemical evaluation emphasized?

The report highlights the need to distinguish rare primary cancers, like MTSCC, from metastasis. Integrated pathology and immunohistochemistry help guide appropriate therapy and accurate diagnosis.

Sep 22, 2026

Uploaded by Ophelia