Synchronous double primary lung carcinomas associated with multiple atypical adenomatous hyperplasia

[Multiple ground-glass opacities nodules]

INTRODUCTION

Ground-glass opacities nodules are frequently detected with the advances of radiological imaging. These can be preinvasive lesions such as atypical adenomatous hyperplasia but also invasive lesions. It leads to question in patients with lung cancer about treatment strategy and follow up.

CASE REPORT

We report the case of a 72 years-old woman followed for a lung adenocarcinoma with an EGFR mutation of the right upper lobe stage IIb. The CT scan shows multiple pure ground-glass opacities in the same lobe of the primitive tumor but also in the other lobe. On the piece of lobectomy, histopathology of two ground-glass opacities showed atypical adenomatous hyperplasia.

CONCLUSION

Ground-glass opacities nodules could be found in patients with an operable lung cancer. These can be multiple and match with atypical adenomatous hyperplasia but also carcinomas lesions. The radiological surveillance is still the standard. The strategy for surgical resection has to be defined especially in case of multiple lesions which can require repeated surgical resection.

Increased expressions of claudin 4 and 7 in atypical adenomatous hyperplasia and adenocarcinoma of the lung

Abnormal expression of claudin (Cldn), the main constituent of tight junctions, may play a crucial role in carcinogenesis. To elucidate these abnormalities of tight junctions in lung adenocarcinoma during carcinogenesis, we examined immunohistochemical expressions of Cldn4 and Cldn7 in human lung resection materials. Lung resection specimens from 86 patients were studied, including 16 atypical adenomatous hyperplasia (AAH), 19 adenocarcinoma in situ (AIS), 32 invasive adenocarcinoma (ADC), 5 AIS with AAH, 2 ADC with AAH, 10 ADC with AIS, and 2 ADC with AIS and AAH. The immunohistochemical staining (IHC) score was defined for both the extent and intensity of staining. IHC score for Cldn4 in AIS and ADC was significantly higher than that in alveolar epithelium (AE) and AAH (p < 0.001 for both). In addition, the AAH score was significantly higher than that in AE (p < 0.001). The Cldn7 score in ADC was significantly increased compared with AE and AAH (p < 0.001 for both). These results suggested that increase of Cldn4-expression may be involved in early molecular events during carcinogenesis of adenocarcinoma, whereas increase of Cldn7-expression may be associated with tumor invasion or progression.

A case of synchronous bilateral lung cancers: EML4-ALK positive adenocarcinoma in the right lung and adenocarcinoma in situ (the former bronchioloalveolar carcinoma) in the left lung

BACKGROUND

Recently it has been revealed that lung adenocarcinomas with distinct gene mutations or fusions are associated with particular histopathological entities. For example, epidermal growth factor receptor (EGFR) gene mutations are often associated with well differentiated adenocarcinoma of the lung with bronchioloalveolar pattern. On the other hand, echinoderm microtubule-associated protein-like 4 (EML4)-anaplastic lymphoma kinase (ALK) fusion gene in a subset of lung adenocarcinoma is related to mucinous cribriform histology.

CASE PRESENTATION

Reported herein is a case of synchronous EML4-ALK positive lung adenocarcinoma and adenocarcinoma in situ in the bilateral lungs of a 55-year-old Japanese woman. The woman had EML4-ALK positive lung adenocarcinoma in the right lower lung while adenocarcinoma in situ in the left upper lung, which was EML4-ALK negative.

CONCLUSION

To our knowledge, this is the first report of synchronous, bilateral lung adenocarcinomas composed of EML4-ALK positive and negative ones.

[Multiple focal pure ground-glass opacities on HRCT images: clinical significance in patients with lung cancer]

BACKGROUND AND OBJECTIVE

Some cases of lung cancer in addition to a primary tumor are associated with multiple pure ground-glass opacities (pGGOs). The objective of this study is to evaluate the clinical significance of multiple pGGOs on CT images of patients with lung cancer. The number, size, distribution, and morphological characteristics of the pGGOs were evaluated. Serial changes in pGGOs that were not surgically resected were analyzed at follow-up CT.

METHODS

The cases of 25 patients with proven lung cancer and associated multiple pGGOs on CT images were retrospectively reviewed.

RESULTS

In total, 207 pGGOs were detected. The size of the opacities ranged from 2 mm to 31 mm in largest diameter. Lung cancer and pGGOs were seen in the same lobe and/or in other lobes. Of the lesions, 183 (88.4%) had a round shape or well-defined border. Histological findings were obtained for 17 lesions representing 87 pGGOs that were surgically resected, namely, 13 atypical adenomatous hyperplasias, 3 bronchioloalveolar carcinomas, and 1 focal fibrosis. Of the 120 pGGOs followed up with CT for a median duration of 61.5 months, 113 (94.2%) retained their size, 1 decreased in size, and 6 disappeared.

CONCLUSIONS

The size of most pGGOs associated with lung cancer did not change during the follow-up period. Most of the lesions histologically diagnosed were atypical adenomatous hyperplasias or bronchioloalveolar carcinomas. The results justify the therapeutic strategy of resecting the primary tumor without therapeutic intervention in the remaining pGGOs.

Clinicopathologic analysis of multiple (five or more) atypical adenomatous hyperplasias (AAHs) of the lung: evidence for the AAH-adenocarcinoma sequence

OBJECTIVE

Clarification of the clinicopathologic characteristics of patients with multiple atypical adenomatous hyperplasias (AAHs).

MATERIALS AND METHODS

The subjects were 1,639 patients who underwent lobectomy or pneumonectomy for lung tumors. The clinicopathologic features of the AAHs in the lung background and the main tumors were examined with regard to the number and the size of the AAHs, the incidence and histology of adenocarcinomas (ADs), and the outcome.

RESULTS

Thirty-two patients (2.0%) had 5 or more AAHs (ranging from 5 to 171), being present predominantly in the upper lobe (86%) and in women (75%). Among the 794 AAHs, 495 (62%) measured less than 1 mm, 170 (22%) measured 1 to less than 2 mm, 118 (15%) measured 2 to less than 5 mm, and 11 (1%) measured 5 to less than 10 mm. Twenty-eight patients (88%) had AD (1 in 18 patients and 2 to 6 in 10 patients). Thirty-two of the 51 patients with ADs (63%) had an AAH component. The incidence of ADs among the total of both AAHs and ADs was 6.0% (51 of 845). The 5-year cancer-free survival rate was 71.4%.

CONCLUSION

Five or more AAHs were seen in the background in 2.0% of lung tumors. Most of the AAHs were small, measuring less than 2 mm, and few exceeded 5 mm. Most of the patients had ADs, which were histologically suggested to be derived from AAH. However, the incidence of the AAH-AD sequence was considered to be low at the tumor basis, and the outcome of ADs was not very favorable.

Clinical, pathological and thin-section CT features of persistent multiple ground-glass opacity nodules: comparison with solitary ground-glass opacity nodule

PURPOSE

To retrospectively compare the clinical, pathological, and thin-section CT features of persistent multiple ground-glass opacity (GGO) nodules with those of solitary GGO nodules.

MATERIALS AND METHODS

Histopathologic specimens were obtained from 193 GGO nodules in 136 patients (87 women, 49 men; mean age, 57; age range 33-81). The clinical data, pathologic findings, and thin-section CT features of multiple and solitary GGO nodules were compared by using t-test or Fisher's exact test.

RESULTS

Multiple GGO nodules (n=105) included atypical adenomatous hyperplasia (AAH) (n=31), bronchioloalveolar carcinoma (BAC) (n=33), adenocarcinoma (n=34) and focal interstitial fibrosis (n=7). Solitary GGO nodules included AAH (n=8), BAC (n=15), adenocarcinoma (n=55) and focal interstitial fibrosis (n=10). AAH (P=.001) and BAC (P=.029) were more frequent in multiple GGO nodules, whereas adenocarcinoma (P<.001) was more frequent in solitary GGO nodules. Female sex (P<.001), nonsmoker (P=.012) and multiple primary lung cancers (P<.001) were more frequent for multiple GGO nodules, which were smaller (12 mm+/-7.9) than solitary GGO nodules (17 mm+/-8.1) (P<.001). Air-bronchogram (P=.019), bubble-lucency (P=.004), and pleural retraction (P<.001) were more frequent in solitary GGO nodules. There was no postoperative recurrence except for one patient with multiple GGO nodules and one with solitary GGO nodule.

CONCLUSION

Clinical, pathological, and thin-section CT features of persistent multiple GGO nodules were found to differ from those of solitary GGO nodules. Nevertheless, the two nodule types can probably be followed up and managed in a similar manner because their prognoses were found to be similar.

Nodular ground-glass opacities on thin-section CT: size change during follow-up and pathological results

OBJECTIVE

To evaluate the inter-group differences in growth and the pathological results of nodular ground-glass opacities (GGOs) according to their size and focal solid portions.

MATERIALS AND METHODS

Ninety-six nodular GGOs in 55 individuals followed by CT for at least one month from an initial chest CT were included. Forty nodular GGOs in 30 individuals were pathologically confirmed to be: adenocarcinoma (n = 15), bronchioloalveolar carcinoma (BAC) (n = 11), atypical adenomatous hyperplasia (AAH) (n = 8), focal interstitial fibrosis (n = 5) and aspergillosis (n = 1). Lesions were categorized based on high-resolution CT findings: pure nodular GGO (PNGGO) < or = 10 mm, PNGGO > 10 mm, mixed nodular GGO (MNGGO) < or = 10 mm, and MNGGO > 10 mm. In each group, the change in size during the follow-up period, the pathological results and the rate of malignancy were evaluated.

RESULTS

Three MNGGO lesions, and none of the PNGGO, grew during the follow-up period. Resected PNGGOs < or = 10 mm were AAH (n = 6), BAC (n = 5), and focal interstitial fibrosis (n = 1). Resected PNGGOs > 10 mm were focal interstitial fibrosis (n = 4), AAH (n = 2), BAC (n = 2), and adenocarcinoma (n = 2). Resected MNGGOs < or = 10 mm were adenocarcinoma (n = 2), and BAC (n = 1). Resected MNGGOs > 10 mm were adenocarcinoma (n = 11), BAC (n = 3), and aspergillosis (n = 1).

CONCLUSION

Mixed nodular GGOs (MNGGOs) had the potential for growth; most were pathologically adenocarcinoma or BAC. By contrast, PNGGOs were stable for several months to years; most were AAH, BAC, or focal interstitial fibrosis.

Surgical treatments for multiple primary adenocarcinoma of the lung

BACKGROUND

The aim of this study was to identify the clinical characteristics of multiple primary adenocarcinomas and to evaluate the efficacy of surgical treatments.

METHODS

Three-hundred sixty-nine patients who underwent pulmonary resection for adenocarcinoma from January 1994 to December 2002 were reviewed.

RESULTS

Thirty-one patients (8.4%) were determined to have multiple primary adenocarcinomas that could be detected on chest x-rays or computed tomography (CT). Twenty-six patients were synchronous and five patients were metachronous with a median interval of 59.0 months. Forty-nine (72.1%) of the total 68 lesions exhibited ground-glass opacity on high-resolution CT (HRCT). Pathologically well-differentiated adenocarcinoma with mixed bronchioloalveolar pattern was the most common subtype (39.7%). Taking into consideration pulmonary function, size, location, and HRCT findings of the lesions the procedures performed were lobectomy with mediastinal lymph-node dissection for 32 patients, segmentectomy with hilar node dissection for 8 patients, and wedge resection for 28 patients. Of 17 patients with bilateral synchronous cancers, simultaneous bilateral pulmonary resection was performed in 14 patients including simultaneous bilateral video-assisted thoracic surgery (VATS) in 11 patients. After a median follow-up period of 27.7 months, the 3-year overall survival rate was 92.9% and the 3-year disease-free survival rates of synchronous cancer and metachronous cancer were 77.9% and 100%, respectively.

CONCLUSIONS

The incidence of multiple primary adenocarcinomas was relatively common. Early radiographic detection and surgical excision could yield a favorable prognosis. The use of VATS, even for synchronous bilateral patients, was a safe and beneficial procedure.

The probability of malignancy in small pulmonary nodules coexisting with potentially operable lung cancer detected by CT

The aim of this study was to assess the probability of malignancy in one or two small nodules 1 cm or less coexisting with potentially operable lung cancer (coexisting small nodules). The preoperative helical CT scans of 223 patients with lung cancer were retrospectively reviewed. The probability of malignancy of coexisting small nodules was evaluated based on nodule size, location, and clinical stage of the primary lung cancers. Seventy-one coexisting small nodules were found on conventional CT in 58 (26%) of 223 patients, and 14 (6%) patients had malignant nodules. Eighteen (25%) of such nodules were malignant. The probability of malignancy was not significantly different between two groups of nodules larger and smaller than 0.5 cm ( p=0.1). The probability of malignancy of such nodules within primary tumor lobe was significantly higher than that in the other lobes ( p<0.01). Metastatic nodules were significantly fewer in clinical stage-IA patients than in the patients with the other stage ( p<0.01); however, four (57%) of seven synchronous lung cancers were located in the non-primary tumor lobes in the clinical stage-I patients. Malignant coexisting small nodules are not infrequent, and such nodules in the non-primary tumor lobes should be carefully diagnosed.

Localized pure ground-glass opacity on high-resolution CT: histologic characteristics

PURPOSE

The aim of this study is to assess the histologic characteristics in cases of localized pure ground-glass opacity (LPGGO) that do not exhibit consolidation on high-resolution CT (HRCT) images.

METHOD

Twenty surgically resected lesions from 20 consecutive cases were retrospectively investigated. Each of the 20 lesions had exhibited LPGGO on HRCT images. The HRCT images and histopathologic findings were examined for correlations.

RESULTS

The areas of LPGGO had a maximum diameter of 2.0-24 mm on the HRCT images. Histopathology of the LPGGO lesions resulted in diagnosis of fibrosis (n = 3; 15%), atypical adenomatous hyperplasia (n = 5; 25%), bronchioloalveolar carcinoma (n = 10; 50%), and adenocarcinoma with stromal invasion (n = 2; 10%). Nonaerogenous components corresponding to solid components without normal alveolar septal destruction were pathologically observed in 15 of the 20 lesions. The diameter of the nonaerogenous components varied between 0.2 and 2.0 mm.

CONCLUSION

Because 10% of LPGGO lesions include invasive disease, patients with LPGGO should undergo pathologic examination for confirmation.

Pulmonary preinvasive neoplasia

Advances in molecular biology have increased our knowledge of the biology of preneoplastic lesions in the human lung. The recently published WHO lung tumour classification defines three separate lesions that are regarded as preinvasive neoplasia. These are (1) squamous dysplasia and carcinoma in situ (SD/CIS), (2) atypical adenomatous hyperplasia (AAH), and (3) diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIP-NECH). SD/CIS is graded in four stages (mild, moderate, severe, and CIS), based upon the distribution of atypical cells and mitotic figures. Most airways showing SD/CIS demonstrate a range of grades; many epithelia are hard to assess and the reproducibility of this complex system remains to be established. Detailed criteria are, however, welcome and provide an objective framework on which to compare various molecular changes. Alterations in gene expression and chromosome structure known to be associated with malignant transformation can be demonstrated in CIS, less so in dysplasias, but also in morphologically normal epithelium. The changes might be sequential, and their frequency and number increase with atypia. Less is known of the "risk of progression" of SD/CIS to invasive "central" bronchial carcinoma. It may take between one and 10 years for invasion to occur, yet the lesion(s) may be reversible if carcinogen exposure ceases. AAH may be an important precursor lesion for peripheral "parenchymal" adenocarcinoma of the lung: the "adenoma" in an adenoma-carcinoma sequence. There is good morphological evidence that AAH may progress from low to high grade to bronchioloalveolar carcinoma (BAC; a non-invasive lesion by definition). Invasion then develops within BAC and peripheral lung adenocarcinoma evolves. The molecular events associated with this progression are not well understood and studies are hampered by a lack of clear criteria to distinguish high grade AAH from BAC. Nonetheless, as with SD/CIS, the patterns of expression of tumour associated genes are consistent with neoplastic progression. We have little idea of the incidence of AAH in the normal or "smoking" populations. It is found more frequently in cancer bearing lungs, especially in those with adenocarcinoma, and is more common in women. No data are available on the risk of progression of AAH. DIPNECH is an exceptionally rare lesion associated with the development of multiple carcinoid tumours. Almost nothing is known of its biology. Knowledge of these lesions will be crucial in the design and understanding of lung cancer screening programmes, where it is likely that the morphological and, more importantly perhaps, the molecular characteristics of these lesions will provide useful targets for detection and possibly even treatment.

Atypical adenomatous hyperplasia of the lung: a probable forerunner in the development of adenocarcinoma of the lung

An increasingly large body of work suggests that atypical adenomatous hyperplasia (AAH) of the lung may be a forerunner of pulmonary adenocarcinoma. Recognizing this fact, the World Health Organization now acknowledges the existence of AAH while noting difficulties that may be encountered in distinguishing AAH from the nonmucinous variant of bronchioloalveolar carcinoma. Regrettably, a universally acceptable definition of morphologic criteria for the diagnosis of AAH has not been achieved. This review of the literature examines the epidemiology, gross appearance, light microscopic findings, morphometry, immunohistochemistry, and molecular features of AAH and suggests a set of histopathologic features that may help the practicing pathologist identify this intriguing lesion. These features include the following: irregularly bordered focal proliferations of atypical cells spreading along the preexisting alveolar framework; prominent cuboidal to low columnar alveolar epithelial cells with variable degree of atypia but less than that seen in adenocarcinoma; increased cell size and nuclear-cytoplasmic ratio with hyperchromasia and prominent nucleoli, generally intact intercellular attachment of atypical cells with occasional empty-looking spaces between them without high cellularity and without tufting or papillary structures; and slight thickening of the alveolar walls on which the AAH cells have spread, with some fibrosis but without scar formation or significant chronic inflammation of the surrounding lung tissue. Several lines of evidence indicate that AAH is a lesion closely associated with adenocarcinoma of the lung, suggesting AAH may be involved in the early stage of a complex multistep carcinogenesis of pulmonary adenocarcinoma.

The association between atypical adenomatous hyperplasia and primary lung cancer

Atypical adenomatous hyperplasia (AAH) has been suggested as the adenoma in an adenoma-carcinoma sequence in the lung periphery. From 1989-1998, we undertook a systematic, prospective search for AAH in lungs resected for cancer. AAH was found in 67 of 554 patients (12. 1%) with primary lung carcinoma (9.2% in male patients and 19.0% in females). AAH was found in lungs bearing adenocarcinoma (23.2%) more frequently than with large cell undifferentiated carcinoma (12.5%) or squamous carcinoma (3.3%). A greater percentage of females with adenocarcinoma had AAH (30.2%) than did males with adenocarcinoma (18.8%). Numbers of AAH ranged from 1-42 per patient and more patients had small numbers of AAH, although 12 patients had 6 or more AAH foci. Larger numbers of AAH tended to be found in adenocarcinoma-bearing lungs. Ten of the 67 patients with AAH and primary lung carcinoma (15%) had multiple primary cancers (range 2-6), all of which were adenocarcinoma. Synchronous cancers were rare in lung tumour-bearing resections without AAH. Patients with AAH show no difference in post-operative survival to those without, for all stages of carcinoma and for Stage I disease alone. This study provides evidence for a strong association between atypical adenomatous hyperplasia and primary lung adenocarcinoma and lends weight to the AAH/adenoma-carcinoma hypothesis.

Prognostic significance of the size of central fibrosis in peripheral adenocarcinoma of the lung

BACKGROUND

The prognostic significance of the characteristics of central fibrosis in peripheral adenocarcinoma of the lung has been reported. However, the prognostic significance of the size of central fibrosis has never been evaluated.

METHODS

A total of 100 consecutive surgically resected peripheral adenocarcinomas of the lung measuring 3.0 cm or less in maximum dimension were reviewed histologically, and the maximum dimension of central fibrosis was measured on conventional hematoxylin and eosin stain.

RESULTS

Median follow-up for patients alive was 54 months. The overall 5-year survival rate was 75%. Twenty-one patients with adenocarcinoma having central fibrosis 5 mm or smaller in maximum dimension had a 5-year survival rate of 100%, whereas the other 79 patients had a 5-year survival less than 70%. Multivariate analysis showed the size of central fibrosis to be an independent prognostic factor as significant as vascular invasion and locoregional lymph node metastasis (p = 0.010, 0.024, and 0.024, respectively).

CONCLUSIONS

The size of central fibrosis is an independent prognostic factor in peripheral lung adenocarcinoma, as significant as the well-established prognostic factors vascular invasion and lymph node metastasis.

Monoclonality of atypical adenomatous hyperplasia of the lung

Atypical adenomatous hyperplasia (AAH) of the lung has been postulated as a possible precursor lesion of bronchioloalveolar carcinoma (BAC). The clonality of AAHs from seven female patients was analyzed to determine whether AAH is a monoclonal expansion. All AAHs were identified in lungs surgically resected for BAC. The clonality of the BAC and bronchiolar metaplasia in each case was also analyzed. Approximately 500 cells in each lesion were precisely microdissected from methanol-fixed sections. Adjacent normal lung tissue was collected as a normal control. DNA was extracted for clonal analysis based on an X-chromosome-linked polymorphic marker, the human androgen receptor gene (HUMARA). HUMARA was found to be amplified with or without previous digestion by the methylation-sensitive restriction endonuclease Hpa II. Five cases were informative. All 10 AAHs and 7 BACs obtained from the informative cases showed monoclonality, whereas the control cells showed polyclonality. Three different AAH lesions in a single case showed both possible patterns of monoclonality. BAC and contiguous AAH showed identical monoclonality in two cases. Two lesions of bronchiolar metaplasia, which was considered reactive, were polyclonal. Our results demonstrated the monoclonal nature of AAH, and this finding suggests that AAH is a precursor of BAC or a preneoplastic condition.